US20160256320A1 - Intraocular shunt placement in the suprachoroidal space - Google Patents

Abstract

Glaucoma can be treated by implanting an intraocular shunt into the eye. Such procedures can employ various deployment devices, shunts, and implantation techniques. A method for treating glaucoma can include injecting a drug into the eye and positioning an intraocular shunt in eye tissue such that the shunt conducts fluid from the anterior chamber to the suprachoroidal space.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS
• This application is a continuation of U.S. patent application Ser. No. 14/313,970, filed Jun. 24, 2014; U.S. patent application Ser. No. 14/313,970 is a continuation-in-part of U.S. patent application Ser. No. 12/946,572, filed on Nov. 15, 2010, now U.S. Pat. No. 8,852,256; U.S. patent application Ser. No. 14/313,970 is also a continuation-in-part of U.S. patent application Ser. No. 12/946,222, filed on Nov. 15, 2010, now abandoned; U.S. patent application Ser. No. 14/313,970 is also a continuation-in-part of U.S. patent application Ser. No. 12/946,240, filed on Nov. 15, 2010, now U.S. Pat. No. 8,828,070; U.S. patent application Ser. No. 14/313,970 is also a continuation-in-part of U.S. patent application Ser. No. 12/946,251, filed on Nov. 15, 2010, now U.S. Pat. No. 9,095,411; U.S. patent application Ser. No. 14/313,970 is also a continuation-in-part of U.S. patent application Ser. No. 12/946,263, filed on Nov. 15, 2010, now U.S. Pat. No. 8,801,766; U.S. patent application Ser. No. 14/313,970 is also a continuation-in-part of U.S. patent application Ser. No. 13/314,927, filed Dec. 8, 2011, now abandoned, which is a continuation-in-part of U.S. patent application Ser. No. 12/946,351, filed on Nov. 15, 2010, now abandoned; U.S. patent application Ser. No. 14/313,970 is also a continuation-in-part of U.S. patent application Ser. No. 12/946,556, filed on Nov. 15, 2010, now abandoned; U.S. patent application Ser. No. 14/313,970 is also a continuation-in-part of U.S. patent application Ser. No. 14/263,957, filed on Apr. 28, 2014, now U.S. Pat. No. 9,283,116, which is a continuation of U.S. patent application Ser. No. 12/946,645, filed on Nov. 15, 2010, now U.S. Pat. No. 8,721,702; U.S. patent application Ser. No. 14/313,970 is also a continuation-in-part of U.S. patent application Ser. No. 14/191,340, filed on Feb. 26, 2014, now U.S. Pat. No. 9,192,516, which is a continuation of U.S. patent application Ser. No. 12/946,653, filed on Nov. 15, 2010, now U.S. Pat. No. 8,663,303; U.S. patent application Ser. No. 14/313,970 is also a continuation-in-part of U.S. patent application Ser. No. 12/946,565, filed on Nov. 15, 2010, now U.S. Pat. No. 8,974,511; U.S. patent application Ser. No. 14/313,970 is also a continuation-in-part of U.S. patent application Ser. No. 13/336,758, filed on Dec. 23, 2011, now U.S. Pat. No. 8,852,137, which is a continuation-in-part of U.S. patent application Ser. No. 12/946,351, filed on Nov. 15, 2010, now abandoned, and which is a continuation-in-part of U.S. patent application Ser. No. 12/946,222, filed on Nov. 15, 2010, now abandoned; U.S. patent application Ser. No. 14/313,970 is also a continuation-in-part of U.S. patent application Ser. No. 13/336,803, filed on Dec. 23, 2011, now U.S. Pat. No. 8,758,290, which is a continuation-in-part of U.S. patent application Ser. No. 12/946,351, filed on Nov. 15, 2010, now abandoned, and which is a continuation-in-part of U.S. patent application Ser. No. 12/946,222, filed on Nov. 15, 2010, now abandoned; U.S. patent application Ser. No. 14/313,970 is also a continuation-in-part of U.S. patent application Ser. No. 13/895,170, filed on May 15, 2013, which is a continuation of International Pat. App. No. PCT/US2011/060820, filed on Nov. 15, 2011, which claims the benefit of and priority to U.S. patent application Ser. No. 12/946,210, filed on Nov. 15, 2010, now U.S. Pat. No. 8,308,701; and U.S. patent application Ser. No. 14/313,970 is also a continuation-in-part of U.S. patent application Ser. No. 13/952,543, filed on Jul. 26, 2013, now U.S. Pat. No. 9,017,276, which is a continuation of U.S. patent application Ser. No. 12/946,542, filed on Nov. 15, 2010, now abandoned; the entireties of each of these applications and patents are incorporated herein by reference.
BACKGROUND
• 1. Field of the Inventions
• The present inventions generally relate to surgical methods, implantation devices, and shunts that can be used to treat glaucoma.
• 2. Description of the Related Art
• Glaucoma is a disease of the eye that affects millions of people. Glaucoma is associated with an increase in intraocular pressure resulting either from a failure of a drainage system of an eye to adequately remove aqueous humor from an anterior chamber of the eye or overproduction of aqueous humor by a ciliary body in the eye. Build-up of aqueous humor and resulting intraocular pressure may result in irreversible damage to the optic nerve and the retina, which may lead to irreversible retinal damage and blindness. Glaucoma affects 1 in 200 people aged fifty and younger, and 1 in 10 over the age of eighty for a total of approximately 70 million people worldwide, and glaucoma is the second leading cause of blindness in the world.
• There are two main types of glaucoma, “open angle” and “closed angle” glaucoma. Open angle glaucoma refers to glaucoma cases in which intraocular pressure increases but an anterior chamber angle (drainage angle) of an eye remains open. A common cause of open angle glaucoma is blockage in the trabecular meshwork, the fluid flow pathways that normally drain aqueous humor from the anterior chamber of the eye. Closed angle glaucoma refers to glaucoma cases in which intraocular pressure increases due to partial or complete closure of the anterior chamber angle. In closed angle glaucoma, swelling or movement of the iris closes the anterior chamber angle and blocks fluid from accessing to the trabecular meshwork, which in turn obstructs outflow of the aqueous humor from the eye.
• Generally, glaucoma may be treated by surgical intervention that involves placing a shunt in the eye to result in production of fluid flow pathways between the anterior chamber and various structures of the eye involved in aqueous humor drainage (e.g., Schlemm's canal, the sclera, or the subconjunctival space). Such fluid flow pathways allow for aqueous humor to exit the anterior chamber. Generally, the surgical intervention to implant the shunt involves inserting into the eye a delivery device that holds an intraocular shunt, and deploying the shunt within the eye.
• A delivery device holding the shunt enters the eye through a cornea (ab interno approach), and is advanced across the anterior chamber. The delivery device is advanced through the sclera until a distal portion of the device is in proximity to a drainage structure of the eye. The shunt is then deployed from the delivery device, producing a conduit between the anterior chamber and various structures of the eye involved in aqueous humor drainage (e.g., Schlemm's canal, the sclera, or the subconjunctival space). See for example, Yu et al. (U.S. Pat. No. 6,544,249 and U.S. Pat. Pub. No. 2008/0108933) and Prywes (U.S. Pat. No. 6,007,511). Such fluid flow pathways allow for aqueous humor to exit the anterior chamber, thereby reducing IOP.
• Such a surgical procedure requires an optical apparatus, such as a goniolens, so that a surgeon may visualize the delivery device within the eye and ensure proper placement of the shunt after it has been deployed from the delivery device.
• Further, various manual and automated deployment devices for implanting an intraocular shunt have been described. See, for example, U.S. Pat. No. 6,544,249 and U.S. Pat. Pub. No. 2008/0108933. Most deployment devices are coupled to a hollow needle which holds the intraocular shunt. Whether an ab externo approach or an ab interno approach is used, the needle is inserted into the eye to deploy the intraocular shunt into the eye. The needle is then withdrawn from the eye.
SUMMARY
• A problem with treating closed angle glaucoma with surgical intervention is that the closed anterior chamber angle prevents an operator from advancing the deployment device into the anterior chamber angle, and thus the device cannot be properly positioned to deploy an intraocular shunt.
• The present inventions generally relate, among other things, to methods for treating closed angle glaucoma that involve using a deployment device that is configured to both re-open a partially or completely closed anterior chamber angle and deploy an intraocular shunt. By re-opening the anterior chamber angle, the deployment device is provided access to the anterior chamber angle so that an operator may properly position the device to deploy the intraocular shunt, thereby generating a fluid flow pathway for outflow of aqueous humor from an anterior chamber of an eye.
• In certain aspects, some methods involve inserting into an eye a deployment device configured to hold an intraocular shunt, using the device to re-open an at least partially closed anterior chamber angle of an eye, and deploying the shunt from the device. Deploying the shunt results in a flow path from an anterior chamber of the eye to an area of lower pressure. Exemplary areas of lower pressure include intra-Tenon's space, the subconjunctival space, the episcleral vein, the subarachnoid space, the suprachoroidal space, Schlemm's canal, or drainage structures associated with the intra-scleral space.
• In other aspects, some methods involve inserting into an eye a deployment device configured to hold an intraocular shunt, advancing the device such that a protrusion on a distal end of the device advances into an at least partially closed anterior chamber angle of the eye, thereby re-opening the closed angle, and deploying the shunt from the device. In certain embodiments, a distal portion of the device includes a sleeve and a hollow shaft that is movable within the sleeve.
• The present inventions generally provide improved shunts that facilitate drainage of fluid from an organ. Particularly, some embodiments of the shunt address and solve the problems with intraocular shunts.
• The present inventions also generally relate to devices for deploying intraocular shunts from a delivery device without use of an optical apparatus that contacts the eye, preferably without use of any optical apparatus. Some devices accomplish shunt deployment without use of an optical apparatus by having a biased distal portion, such that upon entry of the distal portion of the device into an anterior chamber of an eye, the distal portion slides to fit within the anterior chamber angle of the eye. A resistance feedback feature of the device informs an operator that the deployment device is properly positioned within the anterior chamber angle of the eye for deployment and proper placement of the shunt within the eye.
• In particular embodiments, some methods involve inserting into an eye a deployment device configured to hold an intraocular shunt, determining that a distal portion of the device is properly positioned within the eye without use of an optical apparatus that contacts the eye, and deploying the shunt from the device. In certain embodiments, determining involves advancing the device until a resistance is encountered. The resistance indicates to an operator that a distal end of the device has advanced across the anterior chamber of the eye and that a distal portion of the device is fitted within an anterior chamber angle of the eye, and is thereby properly positioned for deployment of the intraocular shunt.
• Another aspect of some embodiments provides methods for deploying a shunt within an eye including inserting into an eye a deployment device configured to hold an intraocular shunt, advancing the device until a protrusion on a distal end of a housing of the device contacts an anterior chamber angle of the eye, thereby providing resistance against further advancement of the device, and deploying the shunt from the device. In certain embodiments, a distal portion of the housing comprises a sleeve and a hollow shaft that is movable within the sleeve.
• In certain embodiments, some devices include a housing having an angled distal end, a deployment mechanism at least partially disposed within the housing, and a hollow shaft coupled to the deployment mechanism, in which the shaft is configured to hold an intraocular shunt. Some devices may further include an intraocular shunt that is at least partially disposed within the shaft. In particular embodiments, the angle of the distal end is substantially identical to an anterior chamber angle of an eye.
• The housing of some devices may include a proximal portion and a distal portion. In certain embodiments, the distal portion of the housing is movable within the proximal portion of the housing. The housing may further include a member that limits axial retraction of the distal portion of the housing.
• In certain embodiments, the distal portion includes a capsule and a sleeve. In other embodiments, a distal end of the sleeve further includes a protrusion. The protrusion may be formed integrally with the distal end of the sleeve or may be connected to a distal end of the sleeve. The protrusion may surround the distal end of the sleeve, or the protrusion may extend around only a portion of the sleeve. In certain embodiments, the protrusion is a collar that surrounds the distal end of the sleeve. In other embodiments, the protrusion includes a flat bottom portion and an angled top portion. In particular embodiments, the angle of the top portion is substantially identical to an anterior chamber angle of an eye.
• Some methods and devices are typically conducted using an ab interno approach. Such an approach is contrasted with an ab externo approach, which involves inserting a deployment device through the conjunctiva of the eye. Although, some methods may be conducted using an ab externo approach.
• Some methods may be performed such that the distal portion of the deployment device or shaft is inserted above or below the corneal limbus. Some methods may be performed such that the distal portion of the deployment device or shaft is inserted into the eye without removing an anatomical feature of the eye, such as the trabecular meshwork, the iris, the cornea, and the aqueous humor. In certain embodiments, some methods may be conducted without inducing substantial ocular inflammation such as, for example, subconjunctival blebbing or endophthalmitis.
• The deployment configuration involves engagement of the deployment mechanism. In certain embodiments, the deployment mechanism may include a two stage system. The first stage is a pusher component and the second stage is a retraction component. Rotation of the deployment mechanism sequentially engages the pusher component and then the retraction component. The pusher component pushes the shunt to partially deploy the shunt from within the shaft, and the retraction component retracts the shaft from around the shunt. The deployment mechanism further includes at least one member that limits axial movement of the shaft.
• The hollow shaft of the deployment device may have various shapes and sizes. In certain embodiments, a distal end of the shaft is beveled. In particular embodiments, the bevel is a double bevel. In certain embodiments, the angle of the bevel is such that upon insertion of the shaft through the sclera of an eye, the bevel is substantially parallel with the conjunctiva of an eye. In certain embodiments, the hollow shaft is a needle.
• Some devices may be completely automated, partially automated, or completely manual. Some devices may be connected to larger robotic systems or may be used as stand-alone handheld deployment devices. In particular embodiments, the device is a handheld device.
• Some devices may include an indicator that provides feedback to an operator as to the state of the deployment mechanism. The indicator may be any type of indicator known in the art, for example a visual indicator, an audio indicator, or a tactile indicator. In certain embodiments, the indicator is a visual indicator.
• Other aspects of some embodiments provide devices for deploying an intraocular shunt that include a housing, in which a distal end of the housing includes a protrusion, a deployment mechanism at least partially disposed within the housing, and a hollow shaft coupled to the deployment mechanism, in which the shaft is configured to hold an intraocular shunt. The devices may further include an intraocular shunt that is at least partially disposed within the shaft.
• Another aspect of some embodiments provides devices for deploying an intraocular shunt that include a deployment mechanism, a hollow shaft coupled to the deployment mechanism and configured to hold an intraocular shunt, and a member adapted to provide resistance feedback to an operator upon a distal portion of the device contacting an anatomical feature of the eye, such as the sclera. The resistance feedback indicates to an operator that a distal portion of the device is properly positioned to deploy the shunt.
• Another aspect of some embodiments provides devices for deploying an intraocular shunt that include a deployment mechanism, a hollow shaft coupled to the deployment mechanism and configured to hold an intraocular shunt, and means for providing feedback to an operator advancing the shaft. The feedback indicates to an operator that a distal portion of the shaft is properly positioned to deploy the shunt. In certain embodiments, the feedback is resistance feedback.
• Other aspects of some embodiments provide devices for deploying an intraocular shunt including a housing having a proximal portion and a distal portion, in which the distal portion is movable within the proximal portion, a deployment mechanism at least partially disposed within the housing, and a hollow shaft coupled to the deployment mechanism, in which the shaft is configured to hold an intraocular shunt. The devices may further include an intraocular shunt that is at least partially disposed within the shaft.
• Some devices include numerous configurations, such as an insertion configuration, a shaft exposure configuration, and a deployment configuration. The insertion configuration includes the hollow shaft fully disposed within the sleeve. The shaft exposure configuration includes retraction of the capsule to at least partially within the proximal portion of the housing, thereby exposing a distal portion of the hollow shaft from the sleeve.
• Other aspects of some embodiments provide devices for deploying an intraocular shunt that includes a housing, a deployment mechanism at least partially disposed within the housing, and a hollow shaft coupled inside the housing to the deployment mechanism, in which the shaft is configured to hold an intraocular shunt. These devices include an insertion configuration and a deployment configuration and the insertion configuration involves the shaft being fully disposed within the housing. The devices may further include an intraocular shunt that is at least partially disposed within the shaft.
• Further, some embodiments relate to eliminating or at least minimizing damage to the eye of a patient during an intraocular shunt placement procedure. Intraocular shunts are typically deployed into the eye using a deployment device that includes or is coupled to a hollow shaft, such as a needle, that holds the intraocular shunt. The hollow shaft of the deployment device is inserted into the eye, then the shunt is deployed into the eye from the deployment device. Once inserted into the eye, the interaction between the hollow shaft of the deployment device and surrounding eye tissue oftentimes causes the shaft to become stuck in the surrounding eye tissue (due to frictional resistance, for example), which can cause severe eye trauma upon shunt deployment or withdrawal of the shaft from the eye. This trauma is avoided or at least minimized in some embodiments by loosening the hollow shaft from the surrounding eye tissue prior to deploying the shunt into the eye from the deployment device and/or withdrawing the hollow shaft from the eye.
• The present inventions provide improved methods for implantation of intraocular shunts. In one aspect, some methods involve the insertion into the eye of a portion of a deployment device comprising an intraocular shunt, loosening the portion of deployment device from the surrounding eye tissue, deploying the shunt into the eye from the deployment device, then withdrawing the portion of the deployment device from the eye. In one particular embodiment, the methods involve inserting into the eye a portion of a deployment device comprising an intraocular shunt without removing an anatomical feature of the eye, loosening the portion of the deployment device from the surrounding eye tissue, deploying the shunt into the eye from the deployment device, then withdrawing the portion of the deployment device from the eye. Loosening of the portion of the deployment device inserted into the eye from the surrounding eye tissue can be achieved, for example, by rotating the deployment device or a portion of the deployment device, other than the portion inserted into the eye. Rotation of the deployment device, or portion thereof, causes the portion of the deployment device inserted into the eye to also rotate, thereby loosening the deployment device from the surrounding eye tissue. Examples of eye tissue surrounding the portion of the deployment device inserted into the eye include, without limitation, the scleral tissue and/or the trabecular meshwork.
• The loosening and deployment steps of some methods do not have to be conducted in any particular order. For example, some methods may involve inserting into the eye a portion of a deployment device comprising an intraocular shunt, deploying the shunt into the eye from the deployment device, loosening the portion of the deployment device from the surrounding eye tissue, then withdrawing the portion of the deployment device from the eye.
• The deployment device may be configured such that a proximal portion of the deployment device is rotated to loosen the portion of the deployment device in the eye from the surrounding eye tissue before or after deploying the shunt into the eye. Alternatively, the deployment device may be configured such that a distal portion of the deployment device is rotated to loosen the portion of the deployment device in the eye from the surrounding eye before or after deploying the shunt into the eye. In yet another embodiment, the entire deployment device may be rotated to loosen the portion of the deployment device in the eye from the surrounding eye tissue before or after deploying the shunt into the eye. Preferably, the deployment device, or a portion thereof, is rotated about its longitudinal axis. Rotation can be in a clockwise or counterclockwise direction.
• In another aspect, the present inventions relate to methods for implanting an intraocular shunt into an eye by inserting into the eye a portion of a deployment device comprising an intraocular shunt, whereby insertion into the eye is at an angle above or below the corneal limbus, rather than through the corneal limbus. Preferably, the portion of the deployment device is inserted into the eye at an angle above the corneal limbus. For example, a portion of a deployment device comprising an intraocular shunt is inserted into the eye approximately 1 mm to 2 mm above the corneal limbus, or any specific value within said range, e.g., 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm or 2 mm above the corneal limbus. The shunt is then deployed into the eye from the deployment device, and the portion of the deployment device is withdrawn from the eye. Shunt implantation methods above or below the corneal limbus are preferably coupled with the step of loosening the deployment device from the surrounding eye tissue before or after deploying the shunt into the eye, as previously described.
• Preferably, some methods are conducted using an ab interno approach by inserting a portion of a deployment device comprising an intraocular shunt through the cornea, across the anterior chamber, through the sclera and into an aqueous humor drainage structure such as the intra-Tenon's space, the subconjunctival space, the episcleral vein the suprachoroidal space or Schlemm's canal. Such an approach is contrasted with an ab externo approach, which may also be used, and which involves inserting the portion of the deployment device comprising an intraocular shunt from the outside of the eye through the conjunctiva and inward through the sclera to reach a drainage structure such as Schlemm's canal. Although, some methods may be conducted using an ab externo approach.
• In other certain embodiments, some methods are conducted without the use of an optical apparatus, particularly an optical apparatus that directly contacts the eye, such as a goniolens. In yet other certain embodiments, some methods are conducted using an optical apparatus that does not directly contact the eye, such as an ophthalmic microscope.
• In a particular embodiment, some methods are reversible. That is, intraocular shunts that are implanted into the eye in accordance with some methods can be removed from the eye and a second shunt can be implanted in the eye.
• Deployment of an intraocular shunt into the eye in accordance with some methods results in the formation of a passage that directs aqueous humor fluid flow from an area of high pressure in the eye, typically the anterior chamber, to an area of lower pressure within the eye, such as the intra-Tenon's space, the subconjunctival space, the episcleral vein, the suprachoroidal space or Schlemm's canal. Alternatively, the shunt is deployed in accordance with some methods such that it form a passage that directs aqueous humor fluid flow from an area of high pressure, such as the anterior chamber, to an area of lower pressure within the head, such as the subarachnoid space. In a preferred embodiment, deployment of an intraocular shunt in accordance with some methods results in the formation of a passage that directs aqueous humor fluid flow from the anterior chamber of the eye to the intra-Tenon's space.
• The present inventions generally relate to methods for deploying intraocular shunts into the subconjunctival space the eye while avoiding or minimizing contact with the conjunctiva. In particular, the present inventions provide methods for deploying an intraocular shunt into the eye such that the shunt forms a drainage pathway from the anterior chamber of the eye to the region of the eye that is bound between the sclera and Tenon's capsule, referred to herein as the intra-Tenon's space. Deployment of an intraocular shunt such that the shunt inlet (i.e., the portion of the shunt that receives fluid from an anterior chamber of the eye) terminates in the anterior chamber and the shunt outlet (i.e., the portion of the shunt that directs fluid to the intra-Tenon's space) terminates in the intra-Tenon's space safeguards the integrity of the conjunctiva to allow subconjunctival drainage pathways to successfully form.
• Some methods involve inserting into the eye a hollow shaft that is configured to hold an intraocular shunt, deploying the shunt from the shaft such that the shunt forms a passage from the anterior chamber to the intra-Tenon's space, and withdrawing the hollow shaft from the eye. The hollow shaft may hold the shunt within the interior of hollow shaft. Alternatively, the hollow shaft may hold the shunt on an outer surface of the shaft. In certain embodiments, some methods involve the use of a hollow shaft configured to hold an intraocular shunt, as previously described, wherein a portion of the hollow shaft extends linearly along a longitudinal axis and at least one other portion of the shaft extends off the longitudinal axis, to insert and deploy the intraocular shunt into the eye such that the shunt forms a passage from the anterior chamber to the intra-Tenon's space.
• Optionally, an aqueous fluid is injected into the eye simultaneously with or prior to the insertion and deployment steps of some methods. For example, an aqueous solution may be injected below Tenon's capsule to balloon the capsule away from the sclera and allow positioning of the intraocular shunt in the intra-Tenon's space.
• In certain aspects, the present inventions generally provide shunts composed of a material that has an elasticity modulus that is compatible with an elasticity modulus of tissue surrounding the shunt. In this manner, some embodiments of the shunt are flexibility matched with the surrounding tissue, and thus will remain in place after implantation without the need for any type of anchor that interacts with the surrounding tissue. Consequently, some embodiments of the shunt will maintain fluid flow away for an anterior chamber of the eye after implantation without causing irritation or inflammation to the tissue surrounding the eye.
• Although discussed in the context of the eye, the elasticity modulus of the shunt may be matched to the elasticity modulus of any tissue. Thus, some embodiments of the shunt may be used to drain fluid from any organ. In particular embodiments, the organ is an eye. Some embodiments of the shunt may define a flow path from an area of high pressure in the eye (e.g., an anterior chamber) to an area of lower pressure in the eye (e.g., intra-Tenon's space, the subconjunctival space, the episcleral vein, the suprachoroidal space, and Schlemm's canal).
• In other aspects, the present inventions generally provide shunts in which a portion of the shunt is composed of a flexible material that is reactive to pressure, i.e., an inner diameter of the shunt fluctuates depending upon the pressures exerted on that portion of the shunt. Thus, the flexible portion of the shunt acts as a valve that regulates fluid flow through the shunt. After implantation, intraocular shunts have pressure exerted upon them by tissues surrounding the shunt (e.g., scleral tissue) and pressure exerted upon them by aqueous humor flowing through the shunt. When the pressure exerted on the flexible portion of the shunt by the surrounding tissue is greater than the pressure exerted on the flexible portion of the shunt by the fluid flowing through the shunt, the flexible portion decreases in diameter, restricting flow through the shunt. The restricted flow results in aqueous humor leaving the anterior chamber at a reduced rate.
• When the pressure exerted on the flexible portion of the shunt by the fluid flowing through the shunt is greater than the pressure exerted on the flexible portion of the shunt by the surrounding tissue, the flexible portion increases in diameter, increasing flow through the shunt. The increased flow results in aqueous humor leaving the anterior chamber at an increased rate.
• The flexible portion of the shunt may be any portion of the shunt. In certain embodiments, the flexible portion is a distal portion of the shunt. In certain embodiments, the entire shunt is composed of the flexible material.
• Other aspects of the present inventions generally provide multi-port shunts. Such shunts reduce probability of the shunt clogging after implantation because fluid can enter or exit the shunt even if one or more ports of the shunt become clogged with particulate. In certain embodiments, the shunt includes a hollow body defining a flow path and more than two ports, in which the body is configured such that a proximal portion receives fluid from the anterior chamber of an eye and a distal portion directs the fluid to a location of lower pressure with respect to the anterior chamber.
• The shunt may have many different configurations. In certain embodiments, the proximal portion of the shunt (i.e., the portion disposed within the anterior chamber of the eye) includes more than one port and the distal portion of the shunt (i.e., the portion that is located in an area of lower pressure with respect to the anterior chamber such as intra-Tenon's space, the subconjunctival space, the episcleral vein, the suprachoroidal space, or Schlemm's canal) includes a single port. In other embodiments, the proximal portion includes a single port and the distal portion includes more than one port. In still other embodiments, the proximal and the distal portions include more than one port.
• The ports may be positioned in various different orientations and along various different portions of the shunt. In certain embodiments, at least one of the ports is oriented at an angle to the length of the body. In certain embodiments, at least one of the ports is oriented 90° to the length of the body.
• The ports may have the same or different inner diameters. In certain embodiments, at least one of the ports has an inner diameter that is different from the inner diameters of the other ports.
• Other aspects of the present inventions generally provide shunts with overflow ports. Those shunts are configured such that the overflow port remains closed until there is a pressure build-up within the shunt sufficient to force open the overflow port. Such pressure build-up typically results from particulate partially or fully clogging an entry or an exit port of the shunt. Such shunts reduce probability of the shunt clogging after implantation because fluid can enter or exit the shunt by the overflow port even if one port of the shunt becomes clogged with particulate.
• In certain embodiments, the shunt includes a hollow body defining an inlet configured to receive fluid from an anterior chamber of the eye and an outlet configured to direct the fluid to a location of lower pressure with respect to the anterior chamber, the body further including at least one slit. The slit may be located at any place along the body of the shunt. In certain embodiments, the slit is located in proximity to the inlet. In other embodiments, the slit is located in proximity to the outlet. In certain embodiments, there is a slit in proximity to both the inlet and the outlet of the shunt.
• In certain embodiments, the slit has a width that is substantially the same or less than an inner diameter of the inlet. In other embodiments, the slit has a width that is substantially the same or less than an inner diameter of the outlet. Generally, the slit does not direct the fluid unless the outlet is obstructed. However, the shunt may be configured such that the slit does direct at least some of the fluid even if the inlet or outlet is not obstructed.
• In other aspects, the present inventions generally provide a shunt having a variable inner diameter. In particular embodiments, the diameter increases from inlet to outlet of the shunt. By having a variable inner diameter that increases from inlet to outlet, a pressure gradient is produced and particulate that may otherwise clog the inlet of the shunt is forced through the inlet due to the pressure gradient. Further, the particulate will flow out of the shunt because the diameter only increases after the inlet.
• In certain embodiments, the shunt includes a hollow body defining a flow path and having an inlet configured to receive fluid from an anterior chamber of an eye and an outlet configured to direct the fluid to a location of lower pressure with respect to the anterior chamber, in which the body further includes a variable inner diameter that increases along the length of the body from the inlet to the outlet. In certain embodiments, the inner diameter continuously increases along the length of the body. In other embodiments, the inner diameter remains constant along portions of the length of the body. Exemplary locations of lower pressure include the intra-Tenon's space, the subconjunctival space, the episcleral vein, the subarachnoid space, and Schlemm's canal.
• In certain embodiments, some embodiments of the shunt may be coated or impregnated with at least one pharmaceutical and/or biological agent or a combination thereof. The pharmaceutical and/or biological agent may coat or impregnate an entire exterior of the shunt, an entire interior of the shunt, or both. Alternatively, the pharmaceutical and/or biological agent may coat and/or impregnate a portion of an exterior of the shunt, a portion of an interior of the shunt, or both. Methods of coating and/or impregnating an intraocular shunt with a pharmaceutical and/or biological agent are known in the art. See, for example, Darouiche (U.S. Pat. Nos. 7,790,183; 6,719,991; 6,558,686; 6,162,487; 5,902,283; 5,853,745; and 5,624,704) and Yu et al. (U.S. Pat. Pub. No. 2008/0108933). The content of each of these references is incorporated by reference herein its entirety.
• In certain embodiments, the exterior portion of the shunt that resides in the anterior chamber after implantation (e.g., about 1 mm of the proximal end of the shunt) is coated and/or impregnated with the pharmaceutical or biological agent. In other embodiments, the exterior of the shunt that resides in the scleral tissue after implantation of the shunt is coated and/or impregnated with the pharmaceutical or biological agent. In other embodiments, the exterior portion of the shunt that resides in the area of lower pressure (e.g., the intra-Tenon's space or the subconjunctival space) after implantation is coated and/or impregnated with the pharmaceutical or biological agent. In embodiments in which the pharmaceutical or biological agent coats and/or impregnates the interior of the shunt, the agent may be flushed through the shunt and into the area of lower pressure (e.g., the intra-Tenon's space or the subconjunctival space).
• Any pharmaceutical and/or biological agent or combination thereof may be used with some embodiments of the shunt. The pharmaceutical and/or biological agent may be released over a short period of time (e.g., seconds) or may be released over longer periods of time (e.g., days, weeks, months, or even years). Exemplary agents include anti-mitotic pharmaceuticals such as Mitomycin-C or 5-Fluorouracil, anti-VEGF (such as Lucintes, Macugen, Avastin, VEGF or steroids).
• The shunts discussed above and herein are described relative to the eye and, more particularly, in the context of treating glaucoma and solving the above identified problems relating to intraocular shunts. Nonetheless, it will be appreciated that shunts described herein may find application in any treatment of a body organ requiring drainage of a fluid from the organ and are not limited to the eye.
• The present inventions provide devices and methods for self-guided implantation of soft gel tissue compliant intraocular shunts in the suprachoroidal space. Shunt placement in the suprachoroidal space avoids contact with the conjunctiva, thus safeguarding the integrity of the conjunctiva. Implanting shunts made of soft, tissue compliant material avoid the creation of a cyclodialysis cleft and reduces or eliminates the risk of hypotony and related side effects.
• Some embodiments of the device accomplish self-guided shunt deployment in the suprachoroidal space by having a flexible hollow shaft with a bend that biases the shunt to follow the scleral spur as it is deployed from the shaft. The hollow shaft is pre-bent to match the angle or arc of the sclera. In a pre-deployment configuration, the shaft is disposed within the device. The rigidity of the device holds the hollow shaft in a straight configuration. Upon its exposure from the device, the hollow shaft reverts to its pre-bent configuration. Such a pre-bend allows the hollow shaft to follow the scleral spur down along the sclera in a self-guided manner to the suprachoroidal space. Additionally, the flexibility of the hollow shaft allows it to continually bend and flex in response to the anatomy as the hollow shaft advances from the device. Once properly positioned, the shunt is deployed from the shaft. The bend in the shaft self-guides the shunt along the scleral spur of the eye as the shaft is retracted into the device and the shunt is deployed from the shaft.
• In certain aspects, some embodiments of the device also include a housing and a deployment mechanism at least partially disposed in the housing. In certain embodiments, the hollow shaft is coupled to the deployment mechanism. The housing may include two components, a proximal portion and a distal portion. The components are configured such that the distal portion is movable within the proximal portion. In certain embodiments, the distal portion of the housing includes a stiff sleeve and the shaft is movably disposed within the sleeve. In other embodiments, the distal portion is without a stiff outer sleeve. As previously described, the shaft is flexible and pre-bent to match an angle of the sclera. In certain embodiments, the distal end of the hollow shaft includes a sharp tip to assist in piercing the sclera. In certain embodiments, the hollow shaft is a flexible needle.
• In other embodiments, a distal end of the sleeve further includes a protrusion. The protrusion may be formed integrally with the distal end of the sleeve or may be connected to a distal end of the sleeve. The protrusion may surround the distal end of the sleeve, or the protrusion may extend around only a portion of the sleeve. In certain embodiments, the protrusion is a collar that surrounds the distal end of the sleeve. In other embodiments, the protrusion includes a flat bottom portion and an angled top portion. In particular embodiments, the angle of the top portion is substantially identical to an anterior chamber angle of an eye.
• Other aspects of some embodiments provide for methods of using the above described devices for inserting a intraocular shunt into the suprachoroidal space of an eye. Such methods involve inserting the above device into an eye and deploying a shunt from the device within the eye such that a proximal portion of the shunt receives fluid from an anterior chamber of an eye and a distal portion of the shunt directs the fluid to the suprachoroidal space. Some methods may also involve injecting a drug into the suprachoroidal space prior to deploying the shunt from the device. Exemplary drugs include drug is a BSS/steroids or antifibrotic agents.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 provides a cross-sectional diagram of the general anatomy of the eye.
• FIG. 2 provides another cross-sectional view the eye, and certain anatomical structures of the eye.
• FIG. 3 depicts, implantation of an intraocular shunt with a distal end of a deployment device holding a shunt, shown in cross-section.
• FIGS. 4A-4B depict a deployment device having a plunger type mechanism for deploying an intraocular shunt into the eye.
• FIG. 5 depicts an example of a deployment device configured to hold an intraocular shunt.
• FIG. 6A depicts a hollow shaft having a bend in a distal portion of the shaft.
• FIG. 6B depicts a hollow shaft having a U-shape.
• FIG. 6C depicts a hollow shaft having a V-shape.
• FIG. 7A depicts a simulation of the exit site distance from the limbus and height above the iris after needle entry at the limbus using an ab interno procedure.
• FIG. 7B depicts a simulation of the exit site distance from the limbus and height above the iris after needle entry above the limbus using an ab interno procedure.
• FIGS. 8 and 9 show an intraocular shunt deployed within the eye. A proximal portion of the shunt resides within the intra-Tenon's space. A middle portion of the shunt resides in the sclera.
• FIG. 10A depicts the tip bevel portion of a triple-ground needle tip.
• FIG. 10B depicts the flat bevel portion of a triple-ground needle tip.
• FIG. 10C depicts an intraocular shunt within a triple-ground needle tip.
• FIG. 10D depicts 100% penetration of the flat bevel portion of a triple-ground needle tip through the sclera of an eye.
• FIG. 11A depicts an intraocular shunt inserted into the scleral channel using a beveled needle tip to completely penetrate the scleral tissue prior to insertion of the shunt.
• FIG. 11B depicts an intraocular shunt inserted into the scleral channel using a beveled needle tip to partially penetrate the scleral tissue prior to insertion of the shunt.
• FIG. 12 provides a schematic of a shunt having a flexible portion.
• FIGS. 13A-13C provide schematics of a shunt implanted into an eye for regulation of fluid flow from the anterior chamber of the eye to a drainage structure of the eye.
• FIGS. 14A-14C show different embodiments of multi-port shunts.FIG. 14A shows an embodiment of a shunt in which the proximal portion of the shunt includes more than one port and the distal portion of the shunt includes a single port.
• FIG. 14B shows another embodiment of a shunt in which the proximal portion includes a single port and the distal portion includes more than one port.
• FIG. 14C shows another embodiment of a shunt in which the proximal portions include more than one port and the distal portions include more than one port.
• FIGS. 15A and 15B show different embodiments of multi-port shunts having different diameter ports.
• FIGS. 16A-16C provide schematics of shunts having a slit located along a portion of the length of the shunt.
• FIG. 17 depicts a shunt having multiple slits along a length of the shunt.
• FIG. 18 depicts a shunt having a slit at a proximal end of the shunt.
• FIGS. 19A and 19B show schematics of shunt that have a variable inner diameter.
• FIGS. 20A-20D depict a shunt having multiple prongs at a distal and/or proximal end.
• FIGS. 21A-21D depict a shunt having a longitudinal slit at a distal and/or proximal end.
• FIG. 22A is a schematic showing an embodiment of a shunt deployment device according to some embodiments.
• FIG. 22B shows a cross sectional view of the device ofFIG. 22A. In this figure, the distal portion of the housing is extended from the proximal portion of the housing.
• FIG. 22C shows a cross sectional view of the device ofFIG. 22A. In this figure, the distal portion of the housing is retracted within the proximal portion of the housing.
• FIG. 22D shows another cross sectional view of an embodiment of the device ofFIG. 22A.
• FIG. 22E is a schematic showing an enlarged view of a protrusion on a distal end of a distal portion of a housing of the device ofFIG. 22A. In this figure, a bottom portion of the protrusion is flat and a top portion of the protrusion is angled.
• FIGS. 23A-23C are schematics showing an enlarged view of a protrusion on a distal end of a distal portion of a housing of some embodiments of the device.
• FIG. 23B is a side view of the protrusion shown inFIG. 23A.
• FIG. 23C is a top view of the protrusion shown inFIG. 23A.
• FIG. 24A shows a deployment device in an insertion configuration and fit into an anterior chamber of an eye.
• FIG. 24B shows a deployment device in an insertion configuration and inserted at too shallow an angled, thus abutting the sclera above the anterior chamber angle.
• FIG. 24C shows a deployment device in an insertion configuration after the protrusion has caused the device to slide down the sclera and be fit into an anterior chamber of an eye.
• FIG. 24D shows a deployment device in an insertion configuration and inserted at too steep an angled, thus abutting the iris below the anterior chamber angle.
• FIG. 24E shows a deployment device in an insertion configuration after the protrusion has caused the device to deflect off of the iris and slide along the iris and be fit into an anterior chamber of an eye.
• FIG. 25 is a schematic showing an embodiment of a shunt deployment device according to some embodiments.
• FIG. 26 shows an exploded view of the device shown inFIG. 25.
• FIGS. 27A-27D are schematics showing different enlarged views of the deployment mechanism of the deployment device with the shaft in a straight configuration, as if the shaft is within the stiff outer sleeve.
• FIGS. 28A-28C are schematics showing interaction of the deployment mechanism with a portion of the housing of the deployment device.
• FIG. 28C shows the shaft in a straight configuration, as if it is within the stiff outer sleeve.
• FIG. 29 depicts a schematic of an exemplary intraocular shunt.
• FIG. 30 shows a cross sectional view of the deployment mechanism of the deployment device with the shaft in a straight configuration, as if the shaft is within the stiff outer sleeve.
• FIG. 31A is a schematic showing deployment some embodiments of the device in a pre-deployment or insertion configuration.
• FIG. 31B shows an enlarged view of the distal portion of the deployment device ofFIG. 31A. This figure shows an intraocular shunt loaded within a hollow shaft of the deployment device and that the shaft is completely disposed within the sleeve of the housing. In this configuration, the hollow shaft is straight.
• FIG. 31C show a schematic of the deployment mechanism in a pre-deployment or insertion configuration.
• FIG. 31D is another schematic showing deployment some embodiments of the device in a pre-deployment or insertion configuration.
• FIGS. 32A-32B are schematics showing insertion of a device into an anterior chamber of the eye, according to some embodiments.FIG. 32A is a magnified view of the position of the distal portion of the device relative to the proximal portion of the device in the insertion configuration.FIG. 32B is a magnified view of the sleeve of the device inserted into the eye. This figure also shows the sleeve and protrusion fitted within an anterior chamber angle of the eye.
• FIG. 33A is a schematic showing extension of the shaft from within the sleeve, which is accomplished by partial retraction of the distal portion of housing to within the proximal portion of housing.
• FIG. 33B is a magnified view of the sleeve of the device inserted into the eye, following a procedure as shown inFIG. 33A.
• FIGS. 34A-34B show schematics of the deployment mechanism at the end of the first stage of deployment of the shunt from the deployment device with the shaft in a straight configuration, as if the shaft is within the stiff outer sleeve.
• FIG. 34C shows an enlarged view of the distal portion of the deployment device ofFIG. 34A. This figure shows an intraocular shunt partially deployed from within a hollow shaft of the deployment device.
• FIG. 34D shows an enlarged view of the distal portion of the deployment device ofFIG. 34A, in which the shaft is shown exposed from the sleeve and is in a bent configuration. This figure shows an intraocular shunt partially deployed from within a hollow shaft of the deployment device.
• FIG. 35A-35B are schematics showing the deployment device after completion of the first stage of deployment of the shunt from the device and in to the eye.FIG. 35A is a magnified view of the position of the distal portion of the device relative to the proximal portion of the device.FIG. 35B is a magnified view of the sleeve of the device inserted into the eye and the shaft extended from the sleeve.
• FIG. 36A show a schematic of the deployment mechanism at the end of the second stage of deployment.
• FIG. 36B shows another schematic of the deployment device at the end of the second stage of deployment.
• FIG. 36C is a magnified view of the sleeve of the device inserted into the eye, retraction of the shaft into the sleeve, and the shunt being deployed from the sleeve.
• FIG. 36D shows another view of the deployment device at the end of the second stage of deployment.
• FIG. 37A is a schematic showing the deployment device after completion of deployment of the shunt from the device and in to the eye.
• FIG. 37B is a magnified view of the sleeve of the device being removed from the eye.
• FIGS. 38A-38E show an intraocular shunt being deployed within the eye, according to another embodiment.
DETAILED DESCRIPTION
• The present inventions generally relate to methods for treating closed angle glaucoma that involve using a deployment device that is configured to both re-open a partially or completely closed anterior chamber angle and deploy an intraocular shunt. In certain aspects, some methods involve inserting into an eye a deployment device configured to hold an intraocular shunt, using the device to re-open an at least partially closed anterior chamber angle of an eye, and deploying the shunt from the device.
• FIG. 1 provides a schematic diagram of the general anatomy of the eye. An anterior aspect of the anterior chamber1 of the eye is thecornea2, and a posterior aspect of the anterior chamber1 of the eye is the iris4. Beneath the iris4 is thelens5. The anterior chamber1 is filled withaqueous humor3. Theaqueous humor3 drains into a space(s)6 below theconjunctiva7 through the trabecular meshwork (not shown in detail) of thesclera8. The aqueous humor is drained from the space(s)6 below theconjunctiva7 through a venous drainage system (not shown).
• FIG. 2 provides a cross-sectional view of a portion of the eye, and provides greater detail regarding certain anatomical structures of the eye. In particular,FIG. 2 shows the relationship of theconjunctiva12 and Tenon'scapsule13. Tenon'scapsule13 is a fascial layer of connective tissue surrounding the globe and extra-ocular muscles. As shown inFIG. 2, it is attached anteriorly to the limbus of the eye and extends posteriorly over the surface of the globe until it fuses with the dura surrounding the optic nerve. InFIG. 2, number9 denotes the limbal fusion of theconjunctiva12 and Tenon'scapsule13 to thesclera11. Theconjunctiva12 and Tenon'scapsule13 are separate membranes that start at the limbal fusion9 and connect to tissue at the posterior of the eye. The space formed below theconjunctiva12 is referred to as the subconjunctival space, denoted asnumber14. Below Tenon'scapsule13 there are Tenon's adhesions that connect the Tenon'scapsule13 to thesclera11. The space between Tenon'scapsule13 and the sclera11 where the Tenon's adhesions connect the Tenon'scapsule13 to thesclera11 is referred to as the intra-Tenon's space, denoted asnumber10.
• In conditions of glaucoma, the pressure of the aqueous humor in the eye (anterior chamber) increases and this resultant increase of pressure can cause damage to the vascular system at the back of the eye and especially to the optic nerve. The treatment of glaucoma and other diseases that lead to elevated pressure in the anterior chamber involves relieving pressure within the anterior chamber to a normal level.
• Glaucoma filtration surgery is a surgical procedure typically used to treat glaucoma. The procedure involves placing a shunt in the eye to relieve intraocular pressure by creating a pathway for draining aqueous humor from the anterior chamber of the eye. The shunt is typically positioned in the eye such that it creates a fluid-flow pathway between the anterior chamber of the eye and a region of lower pressure. Various structures and/or regions of the eye having lower pressure that have been targeted for aqueous humor drainage include Schlemm's canal, the subconjunctival space, the episcleral vein, the suprachoroidal space, or the subarachnoid space. Methods of implanting intraocular shunts are known in the art. Shunts may be implanted using an ab externo approach (entering through the conjunctiva and inwards through the sclera) or an ab interno approach (entering through the cornea, across the anterior chamber, and through the trabecular meshwork and sclera).
• Ab interno approaches for implanting an intraocular shunts have been described and may vary depending on the structure targeted for aqueous humor drainage. For example, ab interno approaches for implanting an intraocular shunt into the subconjunctival space are shown in Yu et al. (U.S. Pat. No. 6,544,249 and U.S. Pat. Pub. No. 2008/0108933) and Prywes (U.S. Pat. No. 6,007,511), the contents of each of which are incorporated by reference herein in its entirety. Briefly and with reference toFIG. 3, a surgical intervention to implant the shunt involves inserting into the eye a portion of a deployment that holds an intraocular shunt, and deploying the shunt within theeye16. The portion of thedeployment device15 holding the shunt enters theeye16 through the cornea17 (ab interno approach). The portion of thedeployment device15 is advanced across the anterior chamber20 (as depicted by the broken line) in what is referred to as a transpupil implant insertion. The portion of thedeployment device15 is advanced through the sclera21 until a distal portion of the device is in proximity to the subconjunctival space. The shunt is then deployed from the deployment device, producing a conduit between the anterior chamber and the subconjunctival space to allow aqueous humor to drain through the conjunctival lymphatic system.
• Previously proposed deployment devices for implanting an intraocular shunt into the eye, whether using an ab externo procedure or an ab interno procedure, typically include a plunger-type mechanism for deploying the shunt into the eye, such as the deployment device illustrated inFIG. 3. The deployment device inFIG. 3 is shown larger inFIG. 4A, and the distal portion of the deployment device is shown magnified inFIG. 4B. As shown inFIGS. 4A and 4B, the deployment device includes anassembly20 that includes ahollow shaft22 defining aninner chamber24. Placed within theinner chamber24 of thehollow shaft22 is a cylindrical inner tube orplunger32 that is coaxial with theshaft22. In the loaded and ready to use condition, theintraocular shunt26 is also placed or otherwise disposed within the hollowinner chamber24 of theshaft22 and is distally located relative toplunger32. Both theintraocular shunt26 andplunger32 may be placed over and supported byoptional guidewire28. The intraocular shunt is deployed into the eye by advancing the plunger to push the intraocular shunt from the shaft into the eye. The shaft is then withdrawn from the eye.
• However, complications can arise when using such deployment devices due to the frictional interaction between the deployment device and the surrounding eye tissue that results upon insertion of the deployment device into the eye and/or deployment of the intraocular shunt into the eye from the deployment device. Moderate to severe eye trauma can occur, beyond any trauma due to insertion of the deployment device, if the portion of the deployment device inserted into the eye is not loosened before or after deployment of the intraocular shunt from the device and prior to withdrawing the portion of the deployment device from the eye.
• The present inventions provide improved methods for implanting an intraocular shunt into the eye while avoiding or at least minimizing the amount of trauma to the eye that is typically involved with shunt implantation procedures. According to some methods, any frictional resistance between the deployment device and surrounding eye tissue that is created upon insertion of a portion of a deployment device in the eye is resolved by loosening the portion of the deployment device from the surrounding eye tissue before or after deployment of the intraocular shunt from the device and prior to withdrawing the portion of the deployment device from the eye. The methods can be used in conjunction with any known shunt deployment device, and in particular, any deployment device that includes a portion for holding an intraocular shunt or is coupled to a hollow shaft which is configured to hold an intraocular shunt.
• Preferably, at least a portion of the deployment device is rotated before the shunt is deployed into the eye from the deployment device, in order to loosen the portion of the device inserted into the eye from the surrounding eye tissue prior to withdrawing the deployment device from the eye. Rotation may be clockwise or counterclockwise, and may be performed manually or in an automated manner. Rotation of only a distal portion of the deployment device may be sufficient to loosen the portion of the deployment device in the eye from the surrounding eye tissue, depending on the configuration of the device. Alternatively, rotation of the entire deployment device serves to loosen the portion of the deployment device in the eye from the surrounding eye tissue. Rotation of the deployment device, or a portion thereof, causes the portion of the deployment device that is inserted into the eye to also rotate, thereby loosening the portion of the deployment device in the eye form the surrounding eye tissue. Examples of surrounding eye tissue include but are not limited to the scleral tissue and the trabecular meshwork.
• The deployment device, or a portion thereof, is rotated clockwise or counterclockwise about the longitudinal axis of the deployment device itself. The rotation about the longitudinal axis is preferably between 1° and 360°, or any specific value within said range, e.g., 1°, 3°, 5°, 10°, 15°, 30°, 45°, 60°, 75°, 90°, 105°, 120°, 135°, 150° 165°, 180°, 195°, 210°, 225°, 240°, 255°, 270°, 285°, 300°, 315°, 330°, 345° or 360°.
• As previously stated, some methods can be used in conjunction with any shunt deployment device.FIG. 5 provides an exemplary schematic of a hollow shaft for use in conjunction with a deployment device in accordance with some methods. This showshollow shaft22 that is configured to hold anintraocular shunt23. The shaft may hold the shunt within thehollow interior24 of theshaft22. Alternatively, the hollow shaft may hold the shunt on anouter surface25 of theshaft22. In particular embodiments, the shunt is held within thehollow interior24 of theshaft22. Generally, in one embodiment, the intraocular shunts are of a cylindrical shape and have an outside cylindrical wall and a hollow interior. The shunt may have an inside diameter of approximately 10-250 microns, an outside diameter of approximately 190-300 microns, and a length of approximately 0.5 mm to 20 mm, such as, for example, 6 mm to 14 mm. Thehollow shaft22 is configured to at least hold a shunt of such shape and such dimensions. However, thehollow shaft22 may be configured to hold shunts of different shapes and different dimensions than those described above, and some embodiments encompass ashaft22 that may be configured to hold any shaped or dimensioned intraocular shunt.
• In some embodiments, the hollow shaft for use in accordance with some methods is straight along the entire length of the shaft. Alternatively, a portion of the hollow shaft extends linearly along a longitudinal axis and at least one other portion of the shaft extends off the longitudinal axis. For example, the hollow shaft may have a bend in the distal portion of the shaft, a U-shape, or an arcuate or V-shape in at least a portion of the shaft. Examples of such hollow shafts suitable for use with some methods include but are not limited to the hollow shafts depicted inFIGS. 6A-6C.
• Preferably, some methods are conducted by making an incision in the eye prior to insertion of the deployment device configured to hold the intraocular shunt. Although in particular embodiments, some methods may be conducted without making an incision in the eye prior to insertion of the deployment device configured to hold the intraocular shunt. In certain embodiments, the distal end of the deployment device (i.e. the portion that is inserted into the eye) has a sharpened point or tip. For example, the distal end of the deployment device includes or is coupled to a needle configured to hold an intraocular shunt. Needles that are configured to hold an intraocular shunt are commercially available from Terumo Medical Corp. (Elkington Md.). In a particular embodiment, the distal end of the deployment device is coupled to a needle having a hollow interior and a beveled tip, and the intraocular shunt is held within the hollow interior of the needle. In another particular embodiment, the distal end of the deployment device is coupled to a needle having a hollow interior and a triple ground point or tip.
• Some methods are preferably conducted without needing to remove an anatomical portion or feature of the eye, including but not limited to the trabecular meshwork, the iris, the cornea, or aqueous humor. Some methods are also preferably conducting without inducing substantial ocular inflammation, such as subconjunctival blebbing or endophthalmitis. Such methods are preferably achieved using an ab interno approach by inserting the deployment device comprising the intraocular shunt through the cornea, across the anterior chamber, through the trabecular meshwork and sclera and into a drainage structure such as Schlemm's canal, the subconjunctival space, the episcleral vein, the suprachoroidal space, the intra-Tenon's space or the subarachnoid space. However, some methods may be conducted using an ab externo approach.
• When some methods are conducted using an ab interno approach, the deployment device is preferably inserted into the eye at an angle above or below the corneal limbus, inserted in contrast with entering through the corneal limbus. Preferably, the deployment device is inserted above the corneal limbus. For example, the deployment device is inserted approximately 0.25 to 3.0 mm, preferably approximately 0.5 to 2.5 mm, more preferably approximately 1.0 mm to 2.0 mm above the corneal limbus, or any specific value within said ranges, e.g., approximately 1.0 mm, approximately 1.1 mm, approximately 1.2 mm, approximately 1.3 mm, approximately 1.4 mm, approximately 1.5 mm, approximately 1.6 mm, approximately 1.7 mm, approximately 1.8 mm, approximately 1.9 mm or approximately 2.0 mm above the corneal limbus.
• Entering at an angle above or below the corneal limbus is advantageous for placing the shunt farther from the limbus at the exit site. It also adds more distance between the shunt and the iris.FIG. 7A demonstrates the change in location of the shunt sclera exit and the height above the iris in the chamber at different angles of entry using a hollow needle configured to hold an intraocular shunt.
• Without intending to be bound by any theory, placement of the shunt farther from the limbus at the exit site, as provided by an angle of entry above the limbus, is believed to provide access to more lymphatic channels for drainage of aqueous humor, such as the episcleral lymphatic network, in addition to the conjunctival lymphatic system. A higher angle of entry also results in flatter placement in the intra-Tenon's space so that there is less bending of the shunt, less pressure on Tenon's capsule, and subsequently less erosion pressure on the conjunctiva via Tenon's capsule.
• For example, as shown inFIG. 7A, shaft entry at thelimbus52 results inexit site distance53 of approximately 1.6 mm from the limbus, and very close proximity to the iris4. Such placement results in a large degree of bending of the shunt, resulting in increased pressure on Tenon's capsule and subsequently on the conjunctiva. In contrast, a high angle ofentry54 above the limbus52 (e.g., 2 mm above the limbus52), results in anexit site distance53 of approximately 2.1 mm from the limbus and a height well above the iris4, as shown inFIG. 7B. Such placement results in flatter placement in the intra-Tenon's space so that there is less bending of the shunt, less pressure on Tenon's capsule, and subsequently less erosion pressure on the conjunctiva via Tenon's capsule.
• Deployment of an intraocular shunt in the eye in accordance with some methods results in the formation of a passage that directs fluid flow from an area of high pressure in the eye, typically the anterior chamber, to an area of lower pressure within the eye or within the head, to relieve or reduce intraocular pressure. Areas of lower pressure within the eye that are suited for aqueous humor drainage include but are not limited to the intra-Tenon's space, the subconjunctival space, the episceleral vein, the suprachoroidal space and Schlemm's canal. Alternatively, the subarachnoid space may provide a drainage outlet for aqueous humor from the anterior chamber. Preferably, deployment of the shunt results in the formation of a passage for directing fluid flow between the anterior chamber and the intra-Tenon's space.
• Deployment of an intraocular shunt such that the inlet (i.e., the portion of the shunt that receives fluid from an anterior chamber of the eye) terminates in the anterior chamber and the outlet (i.e., the portion of the shunt that directs fluid to the intra-Tenon's space) terminates in the intra-Tenon's space provides superior benefits over deployment generally in the subconjunctival space. Deployment of the shunt outlet in the intra-Tenon's space safeguards the integrity of the conjunctiva to allow subconjunctival drainage pathways to successfully form. See, for example, Yu et al., Progress in Retinal and Eye Research, 28: 303-328 (2009)). Additionally, drainage into the intra-Tenon's space provides access to more lymphatic channels than just the conjunctival lymphatic system, such as the episcleral lymphatic network. Moreover, deployment of an intraocular shunt such that the outlet terminates in the intra-Tenon's space avoids having to pierce Tenon's capsule which can otherwise cause complications during glaucoma filtration surgery due to its tough and fibrous nature.
Methods for Intra-Tenon's Shunt Placement
• Some methods involve inserting into the eye a hollow shaft configured to hold an intraocular shunt. In certain embodiments, the hollow shaft is a component of a deployment device that may deploy the intraocular shunt. The shunt is then deployed from the shaft into the eye such that the shunt forms a passage from the anterior chamber to the intra-Tenon's space. The hollow shaft is then withdrawn from the eye.
• Referring toFIGS. 8 and 9, which show an intraocular shunt placed into the eye such that the shunt forms a passage for fluid drainage from the anterior chamber to the intra-Tenon's space. To place the shunt within the eye, a surgical intervention to implant the shunt is preformed that involves inserting into the eye102 adeployment device100 that holds anintraocular shunt101, and deploying at least a portion of theshunt101 withinintra-Tenon's space108, withinsubconjunctival space109 beneath theconjunctiva110. In certain embodiments, ahollow shaft106 of adeployment device100 holding theshunt101 enters theeye102 through the cornea103 (ab interno approach). Theshaft106 is advanced across the anterior chamber104 (as depicted by the broken line) in what is referred to as a transpupil implant insertion. Theshaft106 is advanced through thesclera105 until a distal portion of theshaft106 is in proximity to Tenon'scapsule107. After piercing thesclera105 with thehollow shaft106 of thedeployment device100, resistance to advancement of theshaft106 encountered by an operator of thedeployment device100 informs the operator that theshaft106 has contacted Tenon'scapsule107 and is thus in proximity to Tenon'scapsule107.
• Numerous techniques may be employed to ensure that after piercing thesclera105, thehollow shaft106 does not pierce Tenon'scapsule107. In certain embodiments, some methods involve the use of ahollow shaft106, in which a portion of the hollow shaft extends linearly along a longitudinal axis and at least one other portion of the shaft extends off the longitudinal axis. For example, thehollow shaft106 may have a bend in the distal portion of the shaft, a U-shape, or an arcuate or V-shape in at least a portion of the shaft. Examples of suchhollow shafts106 suitable for use with some methods include but are not limited to thehollow shafts106 depicted inFIGS. 6A-6C. In embodiments in which thehollow shaft106 has a bend at a distal portion of the shaft, intra-Tenon's shunt placement can be achieved by using the bent distal portion of theshaft106 to push Tenon'scapsule107 away from thesclera105 without penetrating Tenon'scapsule107. In these embodiments, the tip of the distal end of theshaft106 does not contact Tenon'scapsule107.
• In other embodiments, a straighthollow shaft106 having a beveled tip is employed. The angle of the beveled tip of the hollow shaft is configured such that after piercing thesclera105, thehollow shaft106 does not pierce Tenon'scapsule107. In these embodiments, theshaft106 is inserted into theeye102 and through thesclera105 at an angle such that the bevel of the tip is parallel to Tenon'scapsule107, thereby pushing Tenon'scapsule107 away from thesclera105, rather than penetrating Tenon'scapsule107, and allowing for deployment of a distal portion of theshunt101 into theintra-Tenon's space108.
• Once a distal portion of thehollow shaft106 is within theintra-Tenon's space108, at least a portion of the device is rotated, thereby reducing the friction between the portion of the device that is in contact with the scleral tissue and the scleral tissue itself. Reduction in friction allows for deployment of the shunt from the device and then removal of the device from the eye without disturbing the tissue of the eye. After rotating the device, theshunt101 is then deployed from theshaft106 of thedeployment device100, producing a conduit between theanterior chamber104 and theintra-Tenon's space108 to allow aqueous humor to drain from the anterior chamber104 (SeeFIGS. 8 and 9).
• In another embodiment, some methods further involves injecting an aqueous solution into the eye below Tenon's capsule in order to balloon the capsule away from the sclera. The increase in intra-Tenon's space caused by the ballooning of Tenon's capsule is helpful for positioning of the outlet of the shunt in the intra-Tenon's space. The solution is injected prior to the shaft piercing the sclera and entering the intra-Tenon's space. Suitable aqueous solutions include but are not limited to Dulbecco's Phosphate Buffered Saline (DPBS), Hank's Balanced Salt Solution (HBSS), Phosphate-Buffered Saline (PBS), Earle's Balanced Salt Solution (EBSS), or other balanced salt solutions known in the art. In some embodiments, some methods involve injecting a viscoelastic fluid into the eye. Preferably, some methods are conducted without the use of a viscoelastic fluid. Some methods can be conducted using any shunt deployment device known in the art. Examples of deployment devices that are suitable for use with some methods include but are not limited to the devices described in U.S. Pat. No. 6,007,511, U.S. Pat. No. 6,544,249, and U.S. Pat. Pub. No. US2008/0108933, the contents of each of which are hereby incorporated by reference in their entireties.
• In certain embodiments, to ensure proper positioning and functioning of the intraocular shunt, the depth of penetration through the sclera is important when conducting some methods. In one embodiment, the distal tip of the hollow shaft pierces the sclera without coring, removing or causing major tissue distortion of the surrounding eye tissue. The shunt is then deployed from the shaft. Preferably, a distal portion of the hollow shaft (as opposed to the distal tip) completely penetrates the sclera before the shunt is deployed from the hollow shaft. In certain embodiments, the hollow shaft is a flat bevel needle, such as a needle having a triple-ground point. The tip bevel first pierces through the sclera making a horizontal slit. In a preferred embodiment of some methods, the needle is advanced even further such that the entire flat bevel penetrates through the sclera, as shown inFIG. 10D, to spread and open the tissue to a full circular diameter. The tip bevel portion190 and flat bevel portion192 of a triple ground needle point, and the configuration of the shunt194 disposed in the needle point, are exemplified as the gray shaded areas inFIGS. 10A-10C. Without intending to be bound by any theory, if the scleral channel is not completely forced open by the flat bevel portion of the needle, the material around the opening may not be sufficiently stretched and a pinching of the implant in that zone will likely occur, causing the shunt to fail. Full penetration of the flat bevel through the sclera causes minor distortion and trauma to the local area. However, this area ultimately surrounds and conforms to the shunt once the shunt is deployed in the eye.
• FIG. 11A depicts an example of an intraocular shunt implanted in an eye in accordance with some methods using a triple ground need point with 100% penetration of the flat bevel in the scleral channel.FIG. 11B depicts an example of a shunt implanted in an eye in accordance with some methods using a triple ground needle point with approximately 50% penetration of the flat bevel in the scleral channel. As shown inFIG. 11B, the shunt is almost completely pinched off as compared to the open shunt depicted inFIG. 11A.
• Some methods may be conducted using any commercially available shunts, such as the Optonol Ex-PRESS mini Glaucoma shunt, and the Solx DeepLight Gold Micro-Shunt. However, some methods are preferably conducted using the intraocular shunts of some embodiments, as described herein.
Intraocular Shunts
• The present inventions also provide intraocular shunts that are configured to form a drainage pathway from the anterior chamber of the eye to the intra-Tenon's space. In particular, the intraocular some embodiments of the shunt have a length that is sufficient to form a drainage pathway from the anterior chamber of the eye to the intra-Tenon's space. The length of the shunt is important in achieving placement specifically in the intra-Tenon's space. A shunt that is too long will extend beyond the intra-Tenon's space and irritate the conjunctiva, which can cause the filtration procedure to fail, as previously described. A shunt that is too short will not provide sufficient access to drainage pathways such as the episcleral lymphatic system or the conjunctival lymphatic system.
• Some embodiments of the shunt may be any length that allows for drainage of aqueous humor from an anterior chamber of an eye to the intra-tenon's space. Exemplary shunts range in length from approximately 0.5 mm to approximately 20 mm or between approximately 4 mm to approximately 16 mm, or any specific value within said ranges. In certain embodiments, the length of the shunt is between approximately 6 to 8 mm, or any specific value within said range, e.g., 6.0 mm, 6.1 mm, 6.2 mm, 6.3 mm, 6.4 mm, 6.5 mm, 6.6 mm, 6.7 mm, 6.8 mm, 6.9 mm, 7 mm, 7.1 mm, 7.2 mm, 7.3 mm, 7.4 mm, 7.5 mm, 7.6 mm, 7.7 mm, 7.8 mm. 7.9 mm, or 8.0 mm.
• The intraocular some embodiments of the shunt are particularly suitable for use in an ab interno glaucoma filtration procedure. Commercially available shunts that are currently used in ab interno filtration procedures are typically made of a hard, inflexible material such as gold, polymer, titanium, or stainless steel, and cause substantial irritation of the eye tissue, resulting in ocular inflammation such as subconjunctival blebbing or endophthalmitis. In contrast, the intraocular some embodiments of the shunt are flexible, and have an elasticity modulus that is substantially identical to the elasticity modulus of the surrounding tissue in the implant site. As such, the intraocular some embodiments of the shunt are easily bendable, do not erode or cause a tissue reaction, and do not migrate once implanted. Thus, when implanted in the eye using an ab interno procedure, such as the methods described herein, the intraocular some embodiments of the shunt do not induce substantial ocular inflammation such as subconjunctival blebbing or endophthalmitis. Additional exemplary features of the intraocular some embodiments of the shunt are discussed in further detail below.
Tissue Compatible Shunts
• In certain aspects, some embodiments generally provide shunts composed of a material that has an elasticity modulus that is compatible with an elasticity modulus of tissue surrounding the shunt (e.g., tissue surrounding the suprachoroidal space). In this manner, some embodiments of the shunt are flexibility matched with the surrounding tissue, and thus will remain in place after implantation without the need for any type of anchor that interacts with the surrounding tissue. Consequently, some embodiments of the shunt will maintain fluid flow away for an anterior chamber of the eye after implantation without causing irritation or inflammation to the tissue surrounding the eye.
• Elastic modulus, or modulus of elasticity, is a mathematical description of an object or substance's tendency to be deformed elastically when a force is applied to it. The elastic modulus of an object is defined as the slope of its stress-strain curve in the elastic deformation region:
• $\lambda \stackrel{\mathrm{def}}{=}\frac{\mathrm{Stress}}{\mathrm{Strain}}$
• where lambda (λ) is the elastic modulus; stress is the force causing the deformation divided by the area to which the force is applied; and strain is the ratio of the change caused by the stress to the original state of the object. The elasticity modulus may also be known as Young's modulus (E), which describes tensile elasticity, or the tendency of an object to deform along an axis when opposing forces are applied along that axis. Young's modulus is defined as the ratio of tensile stress to tensile strain. For further description regarding elasticity modulus and Young's modulus, see for example Gere (Mechanics of Materials, 6th Edition, 2004, Thomson), the content of which is incorporated by reference herein in its entirety.
• The elasticity modulus of any tissue can be determined by one of skill in the art. See for example Samani et al. (Phys. Med. Biol. 48:2183, 2003); Erkamp et al. (Measuring The Elastic Modulus Of Small Tissue Samples, Biomedical Engineering Department and Electrical Engineering and Computer Science Department University of Michigan Ann Arbor, Mich. 48109-2125; and Institute of Mathematical Problems in Biology Russian Academy of Sciences, Pushchino, Moscow Region 142292 Russia); Chen et al. (IEEE Trans. Ultrason. Ferroelec. Freq. Control 43:191-194, 1996); Hall, (In 1996 Ultrasonics Symposium Proc., pp. 1193-1196, IEEE Cat. No. 96CH35993, IEEE, New York, 1996); and Parker (Ultrasound Med. Biol. 16:241-246, 1990), each of which provides methods of determining the elasticity modulus of body tissues. The content of each of these is incorporated by reference herein in its entirety.
• The elasticity modulus of tissues of different organs is known in the art. For example, Pierscionek et al. (Br J Ophthalmol, 91:801-803, 2007) and Friberg (Experimental Eye Research, 473:429-436, 1988) show the elasticity modulus of the cornea and the sclera of the eye. The content of each of these references is incorporated by reference herein in its entirety. Chen, Hall, and Parker show the elasticity modulus of different muscles and the liver. Erkamp shows the elasticity modulus of the kidney.
• Some embodiments of the shunt are composed of a material that is compatible with an elasticity modulus of tissue surrounding the shunt. In certain embodiments, the material has an elasticity modulus that is substantially identical to the elasticity modulus of the tissue surrounding the shunt. In other embodiments, the material has an elasticity modulus that is greater than the elasticity modulus of the tissue surrounding the shunt. Exemplary materials includes biocompatible polymers, such as polycarbonate, polyethylene, polyethylene terephthalate, polyimide, polystyrene, polypropylene, poly(styrene-b-isobutylene-b-styrene), or silicone rubber.
• In particular embodiments, some embodiments of the shunt are composed of a material that has an elasticity modulus that is compatible with the elasticity modulus of tissue in the eye, particularly scleral tissue. In certain embodiments, compatible materials are those materials that are softer than scleral tissue or marginally harder than scleral tissue, yet soft enough to prohibit shunt migration. The elasticity modulus for anterior scleral tissue is approximately 2.9±1.4×106 N/m2, and 1.8±1.1×106 N/m2 for posterior scleral tissue. See Friberg (Experimental Eye Research, 473:429-436, 1988). An exemplary material is cross linked gelatin derived from Bovine or Porcine Collagen.
• Some embodiments encompasses shunts of different shapes and different dimensions, and some embodiments of the shunt may be any shape or any dimension that may be accommodated by the eye. In certain embodiments, the intraocular shunt is of a cylindrical shape and has an outside cylindrical wall and a hollow interior. The shunt may have an inside diameter from approximately 10 μm to approximately 250 μm, an outside diameter from diameter from approximately 100 μm to approximately 450 such as approximately 190 μm to approximately 300 μm, and a length from approximately 0.5 mm to approximately 20 mm, such as from approximately 2 mm to approximately 10 mm.
Shunts Reactive to Pressure
• In other aspects, some embodiments generally provide shunts in which a portion of the shunt is composed of a flexible material that is reactive to pressure, i.e., the diameter of the flexible portion of the shunt fluctuates depending upon the pressures exerted on that portion of the shunt.FIG. 12 provides a schematic of ashunt223 having aflexible portion251. In this figure, theflexible portion251 is shown in the middle of theshunt223. However, theflexible portion251 may be located in any portion of the shunt, such as the proximal or distal portion of the shunt. In certain embodiments, the entire shunt is composed of the flexible material, and thus the entire shunt is flexible and reactive to pressure.
• Theflexible portion251 of theshunt223 acts as a valve that regulates fluid flow through the shunt. The human eye produces aqueous humor at a rate of about 2 μl/min for approximately 3 ml/day. The entire aqueous volume is about 0.25 ml. When the pressure in the anterior chamber falls after surgery to about 7-8 mmHg, it is assumed the majority of the aqueous humor is exiting the eye through the implant since venous backpressure prevents any significant outflow through normal drainage structures (e.g., the trabecular meshwork).
• After implantation, intraocular shunts have pressure exerted upon them by tissues surrounding the shunt (e.g., scleral tissue such as the sclera channel and the sclera exit) and pressure exerted upon them by aqueous humor flowing through the shunt. The flow through the shunt, and thus the pressure exerted by the fluid on the shunt, is calculated by the equation:
• $\Phi =\frac{V}{T}=v\pi {\mathrm{<figure-callout\; label="R"\; filenames="US20160256320A1-20160908-D00001.png"\; state="\{\{state\}\}">R</figure-callout>}}^2=\frac{\pi R^4}{8\eta }\left(\frac{-\Delta P}{\Delta x}\right)=\frac{\pi R^4}{8\eta }\frac{\left|\Delta P\right|}{L}$
• where Φ is the volumetric flow rate; V is a volume of the liquid poured (cubic meters); t is the time (seconds); v is mean fluid velocity along the length of the tube (meters/second); x is a distance in direction of flow (meters); R is the internal radius of the tube (meters); ΔP is the pressure difference between the two ends (pascals);11 is the dynamic fluid viscosity (pascal-second (Pa·s)); and L is the total length of the tube in the x direction (meters).
• FIG. 13A provides a schematic of ashunt226 implanted into an eye for regulation of fluid flow from the anterior chamber of the eye to an area of lower pressure (e.g., the intra-Tenon's space, the subconjunctival space, the episcleral vein, the suprachoroidal space, or Schlemm's canal). In certain embodiments, the area of lower pressure is the subarachnoid space. The shunt is implanted such that aproximal end227 of theshunt226 resides in theanterior chamber228 of the eye, and adistal end229 of theshunt226 resides outside of the anterior chamber to conduct aqueous humor from the anterior chamber to an area of lower pressure. Aflexible portion230 of theshunt226 spans at least a portion of the sclera of the eye. As shown inFIG. 13A, the flexible portion spans an entire length of the sclera221.
• When the pressure exerted on theflexible portion230 of theshunt226 by sclera231 (vertical arrows) is greater than the pressure exerted on theflexible portion230 of theshunt226 by the fluid flowing through the shunt (horizontal arrow), theflexible portion230 decreases in diameter, restricting flow through the shunt226 (FIG. 13B). The restricted flow results in aqueous humor leaving theanterior chamber228 at a reduced rate.
• When the pressure exerted on theflexible portion230 of theshunt226 by the fluid flowing through the shunt (horizontal arrow) is greater than the pressure exerted on theflexible portion230 of theshunt226 by the sclera231 (vertical arrows), theflexible portion230 increases in diameter, increasing flow through the shunt226 (FIG. 13C). The increased flow results in aqueous humor leaving theanterior chamber228 at an increased rate.
• Some embodiments encompasses shunts of different shapes and different dimensions, and some embodiments of the shunt may be any shape or any dimension that may be accommodated by the eye. In certain embodiments, the intraocular shunt is of a cylindrical shape and has an outside cylindrical wall and a hollow interior. The shunt may have an inside diameter from approximately 10 μm to approximately 250 μm, an outside diameter from diameter from approximately 100 μm to approximately 450 μm, such as approximately 190 μm to approximately 300 μm, and a length from approximately 0.5 mm to approximately 20 mm, such as from approximately 2 mm to approximately 10 mm.
• In a particular embodiments, the shunt has a length of about 6 mm and an inner diameter of about 64 μm. With these dimensions, the pressure difference between the proximal end of the shunt that resides in the anterior chamber and the distal end of the shunt that resides outside the anterior chamber is about 4.3 mmHg. Such dimensions thus allow the implant to act as a controlled valve and protect the integrity of the anterior chamber.
• It will be appreciated that different dimensioned implants may be used. For example, shunts that range in length from about 0.5 mm to about 20 mm, such as from about 2 mm to about 10 mm, and have a range in inner diameter from about 10 μm to about 100 μm allow for pressure control from approximately 0.5 mmHg to approximately 20 mmHg.
• The material of the flexible portion and the thickness of the wall of the flexible portion will determine how reactive the flexible portion is to the pressures exerted upon it by the surrounding tissue and the fluid flowing through the shunt. Generally, with a certain material, the thicker the flexible portion, the less responsive the portion will be to pressure. In certain embodiments, the flexible portion is a gelatin or other similar material, and the thickness of the gelatin material forming the wall of the flexible portion ranges from about 10 μm thick to about 100 μm thick.
• In a certain embodiment, the gelatin used for making the flexible portion is known as gelatin Type B from bovine skin. An exemplary gelatin is PB Leiner gelatin from bovine skin, Type B, 225 Bloom, USP. Another material that may be used in the making of the flexible portion is a gelatin Type A from porcine skin, also available from Sigma Chemical. Such gelatin is available from Sigma Chemical Company of St. Louis, Mo. under Code G-9382. Still other suitable gelatins include bovine bone gelatin, porcine bone gelatin and human-derived gelatins. In addition to gelatins, the flexible portion may be made of hydroxypropyl methylcellulose (HPMC), collagen, polylactic acid, polylglycolic acid, hyaluronic acid and glycosaminoglycans.
• In certain embodiments, the gelatin is cross-linked. Cross-linking increases the inter- and intramolecular binding of the gelatin substrate. Any method for cross-linking the gelatin may be used. In a particular embodiment, the formed gelatin is treated with a solution of a cross-linking agent such as, but not limited to, glutaraldehyde. Other suitable compounds for cross-linking include 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC). Cross-linking by radiation, such as gamma or electron beam (e-beam) may be alternatively employed.
• In one embodiment, the gelatin is contacted with a solution of approximately 25% glutaraldehyde for a selected period of time. One suitable form of glutaraldehyde is a grade 1G5882 glutaraldehyde available from Sigma Aldridge Company of Germany, although other glutaraldehyde solutions may also be used. The pH of the glutaraldehyde solution should be in the range of 7 to 7.8 and, more particularly, 7.35-7.44 and typically approximately 7.4+/−0.01. If necessary, the pH may be adjusted by adding a suitable amount of a base such as sodium hydroxide as needed.
• Methods for forming the flexible portion of the shunt are shown for example in Yu et al. (U.S. Pat. Pub. No. 2008/0108933), the content of which is incorporated by reference herein in its entirety. In an exemplary protocol, the flexible portion may be made by dipping a core or substrate such as a wire of a suitable diameter in a solution of gelatin. The gelatin solution is typically prepared by dissolving a gelatin powder in de-ionized water or sterile water for injection and placing the dissolved gelatin in a water bath at a temperature of approximately 55° C. with thorough mixing to ensure complete dissolution of the gelatin. In one embodiment, the ratio of solid gelatin to water is approximately 10% to 50% gelatin by weight to 50% to 90% by weight of water. In an embodiment, the gelatin solution includes approximately 40% by weight, gelatin dissolved in water. The resulting gelatin solution should be devoid of air bubbles and has a viscosity that is between approximately 200-500 cp and more particularly between approximately 260 and 410 cp (centipoise).
• Once the gelatin solution has been prepared, in accordance with the method described above, supporting structures such as wires having a selected diameter are dipped into the solution to form the flexible portion. Stainless steel wires coated with a biocompatible, lubricious material such as polytetrafluoroethylene (Teflon) are preferred.
• Typically, the wires are gently lowered into a container of the gelatin solution and then slowly withdrawn. The rate of movement is selected to control the thickness of the coat. In addition, it is preferred that the tube be removed at a constant rate in order to provide the desired coating. To ensure that the gelatin is spread evenly over the surface of the wire, in one embodiment, the wires may be rotated in a stream of cool air which helps to set the gelatin solution and affix film onto the wire. Dipping and withdrawing the wire supports may be repeated several times to further ensure even coating of the gelatin. Once the wires have been sufficiently coated with gelatin, the resulting gelatin films on the wire may be dried at room temperature for at least 1 hour, and more preferably, approximately 10 to 24 hours. Apparatus for forming gelatin tubes are described in Yu et al. (U.S. Pat. Pub. No. 2008/0108933).
• Once dried, the formed flexible portions may be treated with a cross-linking agent. In one embodiment, the formed flexible portion may be cross-linked by dipping the wire (with film thereon) into the 25% glutaraldehyde solution, at pH of approximately 7.0-7.8 and more preferably approximately 7.35-7.44 at room temperature for at least 4 hours and preferably between approximately 10 to 36 hours, depending on the degree of cross-linking desired. In one embodiment, the formed flexible portion is contacted with a cross-linking agent such as gluteraldehyde for at least approximately 16 hours. Cross-linking can also be accelerated when it is performed a high temperatures. It is believed that the degree of cross-linking is proportional to the bioabsorption time of the shunt once implanted. In general, the more cross-linking, the longer the survival of the shunt in the body.
• The residual glutaraldehyde or other cross-linking agent is removed from the formed flexible portion by soaking the tubes in a volume of sterile water for injection. The water may optionally be replaced at regular intervals, circulated or re-circulated to accelerate diffusion of the unbound glutaraldehyde from the tube. The tubes are washed for a period of a few hours to a period of a few months with the ideal time being 3-14 days. The now cross-linked gelatin tubes may then be dried (cured) at ambient temperature for a selected period of time. It has been observed that a drying period of approximately 48-96 hours and more typically 3 days (i.e., 72 hours) may be preferred for the formation of the cross-linked gelatin tubes.
• Where a cross-linking agent is used, it may be desirable to include a quenching agent in the method of making the flexible portion. Quenching agents remove unbound molecules of the cross-linking agent from the formed flexible portion. In certain cases, removing the cross-linking agent may reduce the potential toxicity to a patient if too much of the cross-linking agent is released from the flexible portion. In certain embodiments, the formed flexible portion is contacted with the quenching agent after the cross-linking treatment and, may be included with the washing/rinsing solution. Examples of quenching agents include glycine or sodium borohydride.
• The formed flexible portion may be further coated or impregnated with biologics and/or pharmaceuticals, as discussed herein.
• After the requisite drying period, the formed and cross-linked flexible portion is removed from the underlying supports or wires. In one embodiment, wire tubes may be cut at two ends and the formed gelatin flexible portion slowly removed from the wire support. In another embodiment, wires with gelatin film thereon, may be pushed off using a plunger or tube to remove the formed gelatin flexible portion.
Multi-Port Shunts
• Other aspects of some embodiments generally provide multi-port shunts. Such shunts reduce probability of the shunt clogging after implantation because fluid can enter or exit the shunt even if one or more ports of the shunt become clogged with particulate. In certain embodiments, the shunt includes a hollow body defining a flow path and more than two ports, in which the body is configured such that a proximal portion receives fluid from the anterior chamber of an eye and a distal portion directs the fluid to a location of lower pressure with respect to the anterior chamber. Exemplary areas of lower pressure include intra-Tenon's space, the subconjunctival space, the episcleral vein, the suprachoroidal space, Schlemm's canal, or drainage structures associated with the intra-scleral space. Another exemplary area of lower pressure to which fluid may be drained is the subarachnoid space.
• The shunt may have many different configurations.FIG. 14A shows an embodiment of ashunt232 in which the proximal portion of the shunt (i.e., the portion disposed within the anterior chamber of the eye) includes more than one port (designated asnumbers233ato233e) and the distal portion of the shunt (i.e., the portion that is located in the intra-Tenon's space) includes asingle port234.FIG. 14B shows another embodiment of ashunt232 in which the proximal portion includes asingle port233 and the distal portion includes more than one port (designated asnumbers234ato234e).FIG. 14C shows another embodiment of ashunt232 in which the proximal portions include more than one port (designated asnumbers233ato233e) and the distal portions include more than one port (designated asnumbers234ato234e). WhileFIGS. 14A-14C show shunts that have five ports at the proximal portion, distal portion, or both, those shunts are only exemplary embodiments. The ports may be located along any portion of the shunt, and some embodiments of the shunt include all shunts having more than two ports. For example, some embodiments of the shunt may include at least three ports, at least four ports, at least five ports, at least 10 ports, at least 15 ports, or at least 20 ports.
• The ports may be positioned in various different orientations and along various different portions of the shunt. In certain embodiments, at least one of the ports is oriented at an angle to the length of the body. In certain embodiments, at least one of the ports is oriented 90° to the length of the body. See for exampleFIG. 14A, which depictsports233a,233b,233d, and233eas being oriented at a 90° angle to port233c.
• The ports may have the same or different inner diameters. In certain embodiments, at least one of the ports has an inner diameter that is different from the inner diameters of the other ports.FIGS. 15A-15B show embodiments of ashunt232 having multiple ports (233aand233b) at a proximal end and asingle port234 at a distal end.FIG. 15A shows thatport233bhas an inner diameter that is different from the inner diameters ofports233aand234. In this figure, the inner diameter ofport233bis less than the inner diameter ofports233aand234. An exemplary inner diameter ofport233bis from about 20 μm to about 40 particularly about 30 In other embodiments, the inner diameter of port33bis greater than the inner diameter ofports233aand234. See for exampleFIG. 15B.
• Some embodiments encompasses shunts of different shapes and different dimensions, and some embodiments of the shunt may be any shape or any dimension that may be accommodated by the eye. In certain embodiments, the intraocular shunt is of a cylindrical shape and has an outside cylindrical wall and a hollow interior. The shunt may have an inside diameter from approximately 10 μm to approximately 250 an outside diameter from approximately 190 μm to approximately 300 and a length from approximately 0.5 mm to approximately 20 mm. Some embodiments of the shunt may be made from any biocompatible material. An exemplary material is gelatin. Methods of making shunts composed of gelatin are described above.
• Shunts with Overflow Ports
• Other aspects of some embodiments generally provide shunts with overflow ports. Those shunts are configured such that the overflow port remains partially or completely closed until there is a pressure build-up within the shunt sufficient to force open the overflow port. Such pressure build-up typically results from particulate partially or fully clogging an entry or an exit port of the shunt. Such shunts reduce probability of the shunt clogging after implantation because fluid can enter or exit the shunt by the overflow port even if one port of the shunt becomes clogged with particulate.
• In certain embodiments, the shunt includes a hollow body defining an inlet configured to receive fluid from an anterior chamber of an eye and an outlet configured to direct the fluid to the intra-Tenon's or intrascleral space, or other areas of lower pressure disclosed herein, the body further including at least one slit. The slit may be located at any place along the body of the shunt.FIG. 16A shows ashunt235 having aninlet236, anoutlet237, and aslit238 located in proximity to theinlet236.FIG. 16B shows ashunt235 having aninlet236, anoutlet237, and aslit239 located in proximity to theoutlet237.FIG. 16C shows ashunt235 having aninlet236, anoutlet237, aslit238 located in proximity to theinlet236, and aslit239 located in proximity to theoutlet237.
• WhileFIGS. 16A-16B show shunts have only a single overflow port at the proximal portion, the distal portion, or both the proximal and distal portions, those shunts are only exemplary embodiments. The overflow port(s) may be located along any portion of the shunt, and some embodiments of the shunt include shunts having more than one overflow port. In certain embodiments, some embodiments of the shunt include more than one overflow port at the proximal portion, the distal portion, or both. For example,FIG. 17 shows ashunt240 having aninlet241, anoutlet242, and slits243aand243blocated in proximity to theinlet241. Some embodiments of the shunt may include at least two overflow ports, at least three overflow ports, at least four overflow ports, at least five overflow ports, at least 10 overflow ports, at least 15 overflow ports, or at least 20 overflow ports. In certain embodiments, some embodiments of the shunt include two slits that overlap and are oriented at 90° to each other, thereby forming a cross.
• In certain embodiments, the slit may be at the proximal or the distal end of the shunt, producing a split in the proximal or the distal end of the implant.FIG. 18 shows an embodiment of ashunt244 having aninlet245,outlet246, and aslit247 that is located at the proximal end of the shunt, producing a split in theinlet245 of the shunt.
• In certain embodiments, the slit has a width that is substantially the same or less than an inner diameter of the inlet. In other embodiments, the slit has a width that is substantially the same or less than an inner diameter of the outlet. In certain embodiments, the slit has a length that ranges from about 0.05 mm to about 2 mm, and a width that ranges from about 10 μm to about 200 μm. Generally, the slit does not direct the fluid unless the outlet is obstructed. However, the shunt may be configured such that the slit does direct at least some of the fluid even if the inlet or outlet is not obstructed.
• Some embodiments encompasses shunts of different shapes and different dimensions, and some embodiments of the shunt may be any shape or any dimension that may be accommodated by the eye. In certain embodiments, the intraocular shunt is of a cylindrical shape and has an outside cylindrical wall and a hollow interior. The shunt may have an inside diameter from approximately 10 μm to approximately 250 μm, an outside diameter from diameter from approximately 100 μm to approximately 450 μm, such as approximately 190 μm to approximately 300 μm, and a length from approximately 0.5 mm to approximately 20 mm, such as from approximately 2 mm to approximately 10 mm. Some embodiments of the shunt may be made from any biocompatible material. An exemplary material is gelatin. Methods of making shunts composed of gelatin are described above.
Shunts Having a Variable Inner Diameter
• In other aspects, some embodiments generally provide a shunt having a variable inner diameter. In particular embodiments, the diameter increases from inlet to outlet of the shunt. By having a variable inner diameter that increases from inlet to outlet, a pressure gradient is produced and particulate that may otherwise clog the inlet of the shunt is forced through the inlet due to the pressure gradient. Further, the particulate will flow out of the shunt because the diameter only increases after the inlet.
• FIGS. 19A-19B show embodiments of ashunt248 having aninlet249 configured to receive fluid from an anterior chamber of an eye and anoutlet250 configured to direct the fluid to a location of lower pressure with respect to the anterior chamber, in which the body further includes a variable inner diameter that increases along the length of the body from theinlet249 to theoutlet250. In certain embodiments, the inner diameter continuously increases along the length of the body, for example as shown inFIG. 19A. In other embodiments, the inner diameter remains constant along portions of the length of the body, as shown inFIG. 19B.
• In exemplary embodiments, the inner diameter may range in size from about 10 μm to about 200 μm, and the inner diameter at the outlet may range in size from about 15 μm to about 300 μm. Some embodiments encompasses shunts of different shapes and different dimensions, and some embodiments of the shunt may be any shape or any dimension that may be accommodated by the eye. In certain embodiments, the intraocular shunt is of a cylindrical shape and has an outside cylindrical wall and a hollow interior. The shunt may have an inside diameter from approximately 10 μm to approximately 250 μm, an outside diameter from diameter from approximately 100 μm to approximately 450 μm, such as approximately 190 μm to approximately 300 μm, and a length from approximately 0.5 mm to approximately 20 mm, such as from approximately 2 mm to approximately 10 mm. Some embodiments of the shunt may be made from any biocompatible material. An exemplary material is gelatin. Methods of making shunts composed of gelatin are described above.
Shunts Having Pronged Ends
• In other aspects, some embodiments generally provide shunts for facilitating conduction of fluid flow away from an organ, the shunt including a body, in which at least one end of the shunt is shaped to have a plurality of prongs. Such shunts reduce probability of the shunt clogging after implantation because fluid can enter or exit the shunt by any space between the prongs even if one portion of the shunt becomes clogged with particulate.
• FIGS. 20A-20D show embodiments of ashunt252 in which at least one end of theshunt252 includes a plurality of prongs253a-d.FIGS. 20A-20D show embodiments in which both a proximal end and a distal end of the shunt are shaped to have the plurality of prongs. However, numerous different configurations are envisioned. For example, in certain embodiments, only the proximal end of the shunt is shaped to have the plurality of prongs. In other embodiments, only the distal end of the shunt is shaped to have the plurality of prongs.
• Prongs253a-dcan have any shape (i.e., width, length, height).FIGS. 20A-20B show prongs253a-das straight prongs. In this embodiment, the spacing between the prongs253a-dis the same. In another embodiment shown inFIGS. 20C-20D, prongs253a-dare tapered. In this embodiment, the spacing between the prongs increases toward a proximal and/or distal end of theshunt252.
• FIGS. 20A-20D show embodiments that include four prongs. However, some embodiments of the shunt may accommodate any number of prongs, such as two prongs, three prongs, four prongs, five prongs, six prongs, seven prongs, eight prongs, nine prongs, ten prongs, etc. The number of prongs chosen will depend on the desired flow characteristics of the shunt.
• Some embodiments encompass shunts of different shapes and different dimensions, and some embodiments of the shunt may be any shape or any dimension that may be accommodated by the eye. In certain embodiments, the intraocular shunt is of a cylindrical shape and has an outside cylindrical wall and a hollow interior. The shunt may have an inside diameter from approximately 10 μm to approximately 250 μm, an outside diameter from approximately 100 μm to approximately 450 μm, and a length from approximately 2 mm to approximately 10 mm. Some embodiments of the shunt may be made from any biocompatible material. An exemplary material is gelatin. Methods of making shunts composed of gelatin are described above.
Shunts Having a Longitudinal Slit
• In other aspects, some embodiments generally provide a shunt for draining fluid from an anterior chamber of an eye that includes a hollow body defining an inlet configured to receive fluid from an anterior chamber of the eye and an outlet configured to direct the fluid to a location of lower pressure with respect to the anterior chamber; the shunt being configured such that at least one end of the shunt includes a longitudinal slit. Such shunts reduce probability of the shunt clogging after implantation because the end(s) of the shunt can more easily pass particulate which would generally clog a shunt lacking the slits.
• FIGS. 21A-21D show embodiments of ashunt254 in which at least one end of theshunt254 includes alongitudinal slit255 that produces atop portion256aand abottom portion256bin a proximal and/or distal end of theshunt254.FIGS. 21A-21D show an embodiment in which both a proximal end and a distal end include alongitudinal slit255 that produces atop portion256aand abottom portion256bin both ends of theshunt254. However, numerous different configurations are envisioned. For example, in certain embodiments, only the proximal end of the shunt includeslongitudinal slit255. In other embodiments, only the distal end of the shunt includeslongitudinal slit255.
• Longitudinal slit255 can have any shape (i.e., width, length, height).FIGS. 21A-21B show alongitudinal slit255 that is straight such that the space between thetop portion256aand thebottom portion256bremains the same along the length of theslit255. In another embodiment shown inFIGS. 21C-21D,longitudinal slit255 is tapered. In this embodiment, the space between the top portion245aand thebottom portion256bincreases toward a proximal and/or distal end of theshunt254.
• Some embodiments encompass shunts of different shapes and different dimensions, and some embodiments of the shunt may be any shape or any dimension that may be accommodated by the eye. In certain embodiments, the intraocular shunt is of a cylindrical shape and has an outside cylindrical wall and a hollow interior. The shunt may have an inside diameter from approximately 10 μm to approximately 250 μm, an outside diameter from approximately 100 μm to approximately 450 μm, and a length from approximately 2 mm to approximately 10 mm. Some embodiments of the shunt may be made from any biocompatible material. An exemplary material is gelatin. Methods of making shunts composed of gelatin are described above.
Pharmaceutical Agents
• In certain embodiments, some embodiments of the shunt may be coated or impregnated with at least one pharmaceutical and/or biological agent or a combination thereof. The pharmaceutical and/or biological agent may coat or impregnate an entire exterior of the shunt, an entire interior of the shunt, or both. Alternatively, the pharmaceutical or biological agent may coat and/or impregnate a portion of an exterior of the shunt, a portion of an interior of the shunt, or both. Methods of coating and/or impregnating an intraocular shunt with a pharmaceutical and/or biological agent are known in the art. See for example, Darouiche (U.S. Pat. Nos. 7,790,183; 6,719,991; 6,558,686; 6,162,487; 5,902,283; 5,853,745; and 5,624,704) and Yu et al. (U.S. Pat. Pub. No. 2008/0108933). The content of each of these references is incorporated by reference herein its entirety.
• In certain embodiments, the exterior portion of the shunt that resides in the anterior chamber after implantation (e.g., about 1 mm of the proximal end of the shunt) is coated and/or impregnated with the pharmaceutical or biological agent. In other embodiments, the exterior of the shunt that resides in the scleral tissue after implantation of the shunt is coated and/or impregnated with the pharmaceutical or biological agent. In other embodiments, the exterior portion of the shunt that resides in the area of lower pressure, such as the intrascleral space, the intra-Tenon's space, or the subconjunctival space, after implantation is coated and/or impregnated with the pharmaceutical or biological agent. In embodiments in which the pharmaceutical or biological agent coats and/or impregnates the interior of the shunt, the agent may be flushed through the shunt and into the area of lower pressure (e.g., the intra-Tenon's space or the subconjunctival space).
• Any pharmaceutical and/or biological agent or combination thereof may be used with some embodiments of the shunt. The pharmaceutical and/or biological agent may be released over a short period of time (e.g., seconds) or may be released over longer periods of time (e.g., days, weeks, months, or even years). Exemplary agents include anti-mitotic pharmaceuticals such as Mitomycin-C or 5-Fluorouracil, anti-VEGF (such as Lucintes, Macugen, Avastin, VEGF or steroids).
• Reference is now made toFIG. 22A which shows an embodiment of ashunt deployment device300 according to some embodiments. In some embodiments, thedevice300 may be used to re-open a partially or completely closed anterior chamber angle and deploy an intraocular shunt. WhileFIG. 22A shows a handheld manually operated shunt deployment device, it will be appreciated that some embodiments of the device may be coupled with robotic systems and may be completely or partially automated. As shown inFIG.22A deployment device300 includes a generally cylindrical body orhousing301, however, the body shape ofhousing301 could be other than cylindrical.Housing301 may have an ergonomical shape, allowing for comfortable grasping by an operator.Housing301 is shown with optional grooves302 to allow for easier gripping by a surgeon.
• FIG. 22B shows a cross sectional view ofdevice300. This figure shows thathousing301 includes aproximal portion301aand adistal portion301b. Thedistal portion301bis movable withinproximal portion301a. In this figure,spring mechanism320 includes aspring321 that controls movement ofdistal portion301b.Spring mechanism320 further includes amember322 that acts as a stopper and limits axial retraction ofdistal portion301bwithinproximal portion301a.Spring mechanism320 further includesmembers323 and324 that run the length ofspring321. The ends ofmembers323 and324 includeflanges325 and326 that project inward frommembers323 and324. An end ofdistal portion301bincludesflanges327 and328 that project outward fromdistal portion301b.Flanges325 and326 interact withflanges327 and328 to prevent release ofdistal portion301bfromproximal portion301a. Theflanges325 and326 and327 and328 hold thedistal portion301bin an extended position until a compressive force acts upondistal portion301b, thereby causingdistal portion301bto partially retract withinproximal portion301a.
• Distal portion301bincludes acapsule329 and ahollow sleeve330.Capsule329 andsleeve330 may be formed integrally or may be separate components that are coupled or connected to each other. Thehollow sleeve330 is configured for insertion into an eye and to extend into an anterior chamber of an eye.FIG. 22B showsdistal portion301bofhousing301 extended fromproximal portion301aofhousing301. In this configuration, hollow shaft304 (not shown in this figure) is completely disposed withinsleeve330.FIG. 22C showsdistal portion301bofhousing301 retracted withinproximal portion301aofhousing301. Retraction ofdistal portion301bofhousing301 withinproximal portion301aofhousing301 exposeshollow shaft304, which is discussed in greater detail below.
• Thehollow shaft304 may include a sharpened distal end. With reference toFIG. 22D, thehollow shaft304 may be flexible and pre-bent to follow the scleral spur down along the sclera upon extension of thehollow shaft304 from thesleeve330, which is discussed in greater detail below. The material used for thehollow shaft304 may be any memory shape material, such as spring steel, such that thehollow shaft304 can easily transform from its bent position to a straight cannula when housed within thesleeve330.
• A distal end ofsleeve330 may optionally include a protrusion331 (FIG. 22D).Protrusion331 provides resistance feedback to an operator as the operator is advancing thesleeve330 through an anterior chamber of an eye. Further,protrusion331 can be of a shape and size that it is capable of re-opening a partially or completely closed anterior chamber angle of an eye as an operator is advancing thedevice300 through an anterior chamber of an eye. In a standard ab interno approach (see, for example, Yu et al. U.S. Pat. No. 6,544,249 and U.S. Pat. Pub. No. 2008/0108933) a deployment device holding a shunt enters an eye through a cornea. The deployment device is advanced across the anterior chamber in what is referred to as a transpupil implant insertion. The deployment device is advanced to the sclera on the opposite side of the eye from which the device entered the eye. With some embodiments of the device, upon advancement of thedevice300 across an anterior chamber of the eye, theprotrusion331 at the distal end of thehollow sleeve330 will contact the sclera, providing resistance feedback to an operator that no further advancement of thedevice300 is necessary (seeFIGS. 38A-38E). This feedback also informs the operator that thedevice300 is in proper position for exposure of thehollow shaft304, which will advance through the sclera for deployment of an intraocular shunt. Theprotrusion331, provides adequate surface area at the distal end ofsleeve330, thus preventingsleeve330 from entering the sclera.
• Further, in some embodiments, the deployment device can be advanced into the anterior chamber angle on the opposite side of the eye from which the device entered the eye. With some embodiments of the device, upon advancement of thedevice300 across an anterior chamber of the eye, theprotrusion331 at the distal end of thehollow sleeve330 will contact a partially or completely closed anterior chamber angle, and continued advancement of thedevice300 will result in theprotrusion331 re-opening the partially or completely closed anterior chamber angle. Once re-opened by the protrusion131, thedevice300 can be moved into proper position for exposure of thehollow shaft304, which will advance through the sclera for deployment of an intraocular shunt. Theprotrusion331, provides adequate surface area at the distal end ofsleeve330, thus preventingsleeve330 from entering the tissue of the eye that is blocking access the trabecular meshwork (e.g., the iris).
• In certain embodiments,protrusion331 has a substantially flat bottom portion and an angled top portion (FIG. 22E). In other embodiments,protrusion331 has a slightly tapered top and a slightly tapered bottom with a rounded distal portion (FIGS. 23A-23C).
• Referring back toFIG. 22E, the angle of the top portion is substantially identical to an anterior chamber angle of an eye. Such a shape of the protrusion ensures that some embodiments of the device will also finds its way to fit, such as by conforming and sliding, into the anterior chamber angle of the eye, the place for proper deployment of an intraocular shunt. This is explained with reference toFIGS. 24A to 24E.FIG. 24A showsdevice300 in an insertion configuration and inserted into aneye340. In this figure,protrusion331 at the distal end of thesleeve330 has been advanced across theanterior chamber341 to thesclera342 on the opposite side of theeye340 from which the device entered theeye340.FIG. 24A showsprotrusion331 fitted within theanterior chamber angle343 of theeye340. Ifsleeve330 enters theanterior chamber341 at too shallow an angle, i.e., theprotrusion331 hit thesclera342 above theanterior chamber angle343, the angled top portion of theprotrusion331 causes thesleeve330 to slide down the sclera342 (direction of arrow) until theprotrusion331 is fit within theanterior chamber angle343 of the eye340 (FIGS. 24B and 24C). Thesleeve330 will slide down thesclera342 instead of entering thesclera342 at the contact point because theshaft304 is completely disposed within thesleeve330 and theprotrusion331 provides adequate surface area at the distal end ofsleeve330 to prevent enough force from being generated at the distal end ofsleeve330 that would result insleeve330 entering thesclera342.
• Conversely, ifsleeve330 enters theanterior chamber341 at too steep an angle, i.e., theprotrusion331 hit theiris344 below theanterior chamber angle343, the substantially flat bottom portion of theprotrusion331 causes thesleeve330 to deflect off theiris344 and proceed is a direction parallel to theiris344 until theprotrusion331 is fit within theanterior chamber angle343 of the eye340 (FIGS. 24D and 24E). Thesleeve330 will deflect off theiris344 instead of entering theiris344 at the contact point because theshaft304 is completely disposed within thesleeve330 and theprotrusion331 provides adequate surface area at the distal end ofsleeve330 to prevent enough force from being generated at the distal end ofsleeve330 that would result insleeve330 entering theiris344.
• In certain embodiments,protrusion331 is not required. In these embodiments, thesleeve330 is of a sufficient outer diameter such that the sleeve itself may serve the function of the protrusion as described above. In these embodiments, a distal end of the sleeve is shaped to have a flat bottom portion and an angled top portion. In other embodiments, a goniolens can be used to visualize advancement of the device within the eye, and thus the configuration of the distal end of thesleeve330 is not important for proper shunt deployment using some embodiments of the device.
• Referring back toFIG. 22A, theproximal portion301aof thehousing301 is open at its proximal end, such that a portion of adeployment mechanism303 may extend from the proximal end of theproximal portion301aof thehousing301. Thesleeve330 of thedistal portion301bof thehousing301 is also open such that at least a portion of ahollow shaft304 may extend inside the housing, intosleeve330 of thedistal portion301bof thehousing301, and extend beyond the distal end of thesleeve330 in certain configurations (such as the deployment configuration).Housing301 further includes aslot306 through which an operator, such as a surgeon, using thedevice300 may view anindicator307 on thedeployment mechanism303.
• Housing301 andprotrusion331 may be made of any material that is suitable for use in medical devices. For example,housing301 andprotrusion331 may be made of a lightweight aluminum or a biocompatible plastic material. Examples of such suitable plastic materials include polycarbonate and other polymeric resins such as DELRIN and ULTEM. In certain embodiments,housing301 andprotrusion331 are made of a material that may be autoclaved, and thus allow forhousing301 andprotrusion331 to be re-usable. Alternatively,device300, may be sold as a one-time-use device, and thus the material of the housing and the protrusion does not need to be a material that is autoclavable.
• Deployment into the eye of an intraocular shunt, such as the shunts described herein, in accordance with some methods can be achieved using a hollow shaft configured to hold the shunt, as described herein. The hollow shaft can be coupled to a deployment device or part of the deployment device itself. Deployment devices that are suitable for use with some methods include but are not limited to the deployment devices described in U.S. Pat. No. 6,007,511, U.S. Pat. No. 6,544,249, and U.S. Pat. Pub. No. US2008/0108933, the contents of each of which are hereby incorporated by reference in their entireties. In other embodiments, the deployment devices are devices as described in co-pending and co-owned U.S. patent application Ser. No. 12/946,222 filed on Nov. 15, 2010, the entire content of which is incorporated by reference herein.
• In still other embodiments, some methods are conducted using thedeployment device400 depicted inFIG. 25. WhileFIG. 25 shows a handheld manually operated shunt deployment device, it will be appreciated that some embodiments of the device may be coupled with robotic systems and may be completely or partially automated. As shown inFIG. 25,deployment device400 includes a generally cylindrical body orhousing401, however, the body shape ofhousing401 could be other than cylindrical.Housing401 may have an ergonomical shape, allowing for comfortable grasping by an operator.Housing401 is shown withoptional grooves402 to allow for easier gripping by a surgeon.
• Housing401 is shown having a larger proximal portion that tapers to a distal portion. The distal portion includes ahollow sleeve405. Thehollow sleeve405 is configured for insertion into an eye and to extend into an anterior chamber of an eye. The hollow sleeve is visible within an anterior chamber of an eye. The sleeve may include an edge at a distal end that provides resistance feedback to an operator upon insertion of thedeployment device400 within an eye of a person. Upon advancement of thedevice400 across an anterior chamber of the eye, thehollow sleeve405 will eventually contact the sclera, providing resistance feedback to an operator that no further advancement of thedevice400 is necessary. The edge of thesleeve405, prevents theshaft404 from accidentally being pushed too far through the sclera. Atemporary guard408 is configured to fit aroundsleeve405 and extend beyond an end ofsleeve405. The guard is used during shipping of the device and protects an operator from a distal end of ahollow shaft404 that extends beyond the end of thesleeve405. The guard is removed prior to use of the device.
• Housing401 is open at its proximal end, such that a portion of adeployment mechanism403 may extend from the proximal end of thehousing401. A distal end ofhousing401 is also open such that at least a portion of ahollow shaft404 may extend through and beyond the distal end of thehousing401.Housing401 further includes aslot406 through which an operator, such as a surgeon, using thedevice400 may view anindicator407 on thedeployment mechanism403.
• Housing401 may be made of any material that is suitable for use in medical devices. For example,housing401 may be made of a lightweight aluminum or a biocompatible plastic material. Examples of such suitable plastic materials include polycarbonate and other polymeric resins such as DELRIN and ULTEM. In certain embodiments,housing401 is made of a material that may be autoclaved, and thus allow forhousing401 to be re-usable. Alternatively,device400, may be sold as a one-time-use device, and thus the material of the housing does not need to be a material that is autoclavable.
• Housing401 may be made of multiple components that connect together to form the housing.FIG. 26 shows an exploded view ofdeployment device400. In this figure,housing401, is shown having threecomponents401a,401b, and401c. The components are designed to screw together to formhousing401.FIG. 26 also showsdeployment mechanism403. Thehousing401 is designed such thatdeployment mechanism403 fits within assembledhousing401.Housing401 is designed such that components ofdeployment mechanism403 are movable withinhousing401.
• FIGS. 27A-27D also showdeployment mechanism403. Thehousing401 is designed such thatdeployment mechanism403 fits within assembledhousing401.Housing401 is designed such that components ofdeployment mechanism403 are movable withinhousing401.
• FIGS. 27A-27D show different enlarged views of thedeployment mechanism403.Deployment mechanism403 may be made of any material that is suitable for use in medical devices. For example,deployment mechanism403 may be made of a lightweight aluminum or a biocompatible plastic material. Examples of such suitable plastic materials include polycarbonate and other polymeric resins such as DELRIN and ULTEM. In certain embodiments,deployment mechanism403 is made of a material that may be autoclaved, and thus allow fordeployment mechanism403 to be re-usable. Alternatively,device400 may be sold as a one-time-use device, and thus the material of the deployment mechanism does not need to be a material that is autoclavable.
• Deployment mechanism403 includes adistal portion409 and adistal portion410. Thedeployment mechanism403 is configured such thatdistal portion409 is movable withindistal portion410. More particularly,distal portion409 is capable of partially retracting to withindistal portion410.
• In this embodiment, thedistal portion409 is shown to taper to a connection with ahollow shaft404. This embodiment is illustrated such that the connection between thehollow shaft404 and thedistal portion409 of thedeployment mechanism403 occurs inside thehousing401.Hollow shaft404 may be removable from thedistal portion409 of thedeployment mechanism403. Alternatively, thehollow shaft404 may be permanently coupled to thedistal portion409 of thedeployment mechanism403.
• Generally,hollow shaft404 is configured to hold anintraocular shunt415. An exemplaryintraocular shunt415 in shown inFIG. 29. Other exemplary intraocular shunts are shown in Yu et al. (U.S. Pat. Pub. No. 2008/0108933). Generally, in one embodiment, intraocular shunts are of a cylindrical shape and have an outside cylindrical wall and a hollow interior. The shunt may have an inner diameter of approximately 50 μm to approximately 250 μm, an outside diameter of approximately 190 μm to approximately 300 μm, and a length of approximately 0.5 mm to about 20 mm. Thus,hollow shaft404 is configured to at least hold a shunt of such shape and such dimensions. However,hollow shaft404 may be configured to hold shunts of different shapes and different dimensions than those described above, and some embodiments encompass ashaft404 that may be configured to hold any shaped or dimensioned intraocular shunt. In particular embodiments, the shaft has an inner diameter of approximately 200 μm to approximately 400 μm. In certain embodiments, the shunt is a soft gel shunt, e.g., a gelatin shunt. If a gelatin shunt is used, the shunt is generally wetted inside thehollow shaft404 with a balanced salt solution (e.g., Dulbecco's Phosphate Buffered Saline) or a steroid or other drug prior to implantation. Such priming ensures that the shunt remains flexible before implantation.
• Theshaft404 may be any length. A usable length of the shaft may be anywhere from about 5 mm to about 40 mm, and is 15 mm in certain embodiments. In certain embodiments, the shaft is straight. In other embodiments,shaft404 is of a shape other than straight, for example a shaft having a bend along its length or a shaft having an arcuate portion. Exemplary shaped shafts are shown for example in Yu et al. (U.S. Pat. Pub. No. 2008/0108933). In particular embodiments, the shaft includes a bend at a distal portion of the shaft. In other embodiments, a distal end of the shaft is beveled or is sharpened to a point.
• Theshaft404 may hold the shunt at least partially within the hollow interior of theshaft404. In other embodiments, the shunt is held completely within the hollow interior of theshaft404. Alternatively, the hollow shaft may hold the shunt on an outer surface of theshaft404. In particular embodiments, the shunt is held within the hollow interior of theshaft404. In certain embodiments, the hollow shaft is a needle having a hollow interior. Needles that are configured to hold an intraocular shunt are commercially available from Terumo Medical Corp. (Elkington, Md.).
• A proximal portion of thedeployment mechanism403 includesoptional grooves416 to allow for easier gripping by an operator for easier rotation of the deployment mechanism, which will be discussed in more detail below. Theproximal portion410 of the deployment mechanism also includes at least one indicator that provides feedback to an operator as to the state of the deployment mechanism. The indicator may be any type of indicator known in the art, for example a visual indicator, an audio indicator, or a tactile indicator.FIGS. 27A-27D show a deployment mechanism having two indicators, aready indicator411 and a deployedindicator419.Ready indicator411 provides feedback to an operator that the deployment mechanism is in a configuration for deployment of an intraocular shunt from thedeployment device400. Theready indicator411 is shown in this embodiment as a green oval having a triangle within the oval. Deployedindicator419 provides feedback to the operator that the deployment mechanism has been fully engaged and has deployed the shunt from thedeployment device400. The deployedindicator419 is shown in this embodiment as a yellow oval having a black square within the oval. The indicators are located on the deployment mechanism such that when assembled, theindicators411 and419 may be seen throughslot406 inhousing401.
• Theproximal portion410 includes astationary portion410band arotating portion410a. Theproximal portion410 includes achannel412 that runs part of the length ofstationary portion410band the entire length of rotatingportion410a. Thechannel412 is configured to interact with aprotrusion417 on an interior portion ofhousing component401a(FIGS. 28A and 28B). During assembly, theprotrusion417 onhousing component401ais aligned withchannel412 on thestationary portion410bandrotating portion410aof thedeployment mechanism403. Theproximal portion410 ofdeployment mechanism403 is slid withinhousing component401auntil theprotrusion417 sits withinstationary portion410b(FIG. 28C). Assembled, theprotrusion417 interacts with thestationary portion410bof thedeployment mechanism403 and prevents rotation ofstationary portion410b. In this configuration, rotatingportion410ais free to rotate withinhousing component401a.
• Referring back toFIGS. 27A-27D, the rotatingportion410aofproximal portion410 ofdeployment mechanism403 also includeschannels413a,413b, and413c.Channel413aincludes afirst portion413a1 that is straight and runs perpendicular to the length of therotating portion410a, and asecond portion413a2 that runs diagonally along the length of rotatingportion410a, downwardly toward a proximal end of thedeployment mechanism403.Channel413bincludes afirst portion413b1 that runs diagonally along the length of therotating portion410a, downwardly toward a distal end of thedeployment mechanism403, and a second portion that is straight and runs perpendicular to the length of therotating portion410a. The point at whichfirst portion413a1 transitions tosecond portion413a2 alongchannel413a, is the same as the point at whichfirst portion413b1 transitions tosecond portion413b2 alongchannel413b.Channel413cis straight and runs perpendicular to the length of therotating portion410a. Within each ofchannels413a,413b, and413c, sitmembers414a,414b, and414crespectively.Members414a,414b, and414care movable withinchannels413a,413b, and413c.Members414a,414b, and414calso act as stoppers that limit movement of rotatingportion410a, which thereby limits axial movement of theshaft404.
• FIG. 30 shows a cross-sectional view ofdeployment mechanism403.Member414ais connected to thedistal portion409 of thedeployment mechanism403. Movement ofmember414aresults in retraction of thedistal portion409 of thedeployment mechanism403 to within theproximal portion410 of thedeployment mechanism403.Member414bis connected to apusher component418. Thepusher component418 extends through thedistal portion409 of thedeployment mechanism403 and extends into a portion ofhollow shaft404. The pusher component is involved in deployment of a shunt from thehollow shaft404. An exemplary pusher component is a plunger. Movement ofmember414bengagespusher418 and results inpusher418 advancing withinhollow shaft404.
• Reference is now made toFIGS. 31A-37B, which accompany the following discussion regarding deployment of ashunt415 fromdeployment device400.FIG. 31A showsdeployment device400 in a pre-deployment or insertion configuration. In this configuration,shunt415 is loaded within hollow shaft404 (FIG. 31B). As shown inFIG. 31B,shunt415 is only partially withinshaft404, such that a portion of the shunt is exposed. However, theshunt415 does not extend beyond the end of theshaft404. In other embodiments, theshunt415 is completely disposed withinhollow shaft404. Theshunt415 is loaded intohollow shaft404 such that the shunt abutspusher component418 withinhollow shaft404.
• In the pre-deployment or insertion configuration, thedistal portion401bof thehousing401 is in an extended position, withspring421 in a relaxed state (FIG. 31A). Additionally, in the pre-deployment configuration, theshaft404 is fully disposed within thesleeve430 of thedistal portion401bof the housing401 (FIG. 31B).Pusher418 abuts shunt415 (FIG. 31B).
• Thedeployment mechanism403 is configured such thatmember414aabuts a distal end of thefirst portion413a1 ofchannel413a, andmember414babut a proximal end of thefirst portion413b1 ofchannel413b(FIG. 31C). In this configuration, theready indicator411 is visible throughslot406 of thehousing401, providing feedback to an operator that the deployment mechanism is in a configuration for deployment of an intraocular shunt from the deployment device400 (FIG. 31D). In this configuration, thedevice400 is ready for insertion into an eye (insertion configuration or pre-deployment configuration).
• FIGS. 32A-32B show device400 in the insertion configuration and inserted into aneye440.FIG. 32A is a magnified view of the position of thedistal portion401brelative to theproximal portion401ain the insertion configuration.FIG. 32B is a magnified view of thesleeve430 ofdevice400 inserted into the eye. Any of a variety of methods known in the art may be used to insert some embodiments of the device into an eye. In certain embodiments, some embodiments of the device may be inserted into the eye using an ab externo approach (entering through the conjunctiva) or an ab interno approach (entering through the cornea). In particular embodiment, the approach is an ab interno approach as shown Yu et al. (U.S. Pat. No. 6,544,249 and U.S. Pat. Pub. No. 2008/0108933) and Prywes (U.S. Pat. No. 6,007,511), the content of each of which is incorporated by reference herein in its entirety.
• FIGS. 32A-32B shows an ab interno approach for insertion ofdevice400 into theeye440. InFIG. 32B,protrusion431 at the distal end of thesleeve430 has been advanced across theanterior chamber441 to theanterior chamber angle443 on the opposite side of theeye440 from which the device entered theeye440.FIG. 32B showsprotrusion431 andsleeve430 fitted within theanterior chamber angle443 of theeye440, thus re-opening the partially or completely closedanterior chamber angle443. Further,FIG. 32B illustrates that theprotrusion431 at the distal end of thesleeve430 has been advanced across theanterior chamber441 to thesclera442 on the opposite side of theeye440 from which the device entered theeye440.FIG. 32B showsprotrusion431 andsleeve430 fitted within theanterior chamber angle443 of theeye440. Such insertion and placement is accomplished without the use of an optical apparatus that contacts the eye, such as a goniolens. In certain embodiments this insertion is accomplished without the use of any optical apparatus.
• Insertion without the use of an optical apparatus that contacts the eye, or any optical apparatus, is possible because of various features of the device described above and reviewed here briefly. The shape of theprotrusion431 is such that it corrects for an insertion angle that is too steep or too shallow, ensuring that thesleeve430 is fitted into the anterior chamber angle of the eye, the place for proper deployment of an intraocular shunt. Further, the shape of the protrusion provides adequate surface area at the distal end ofsleeve430 to prevent enough force from being generated at the distal end ofsleeve430 that would result insleeve430 entering an improper portion of the sclera442 (if the insertion angle is too shallow) or entering an improper portion of the iris444 (if the insertion angle is too steep). Additionally, since thehollow shaft404 is fully disposed within thesleeve430, it cannot pierce tissue of the eye until it is extended from thesleeve430. Thus, if the insertion angle is too shallow or too steep, theprotrusion431 can cause movement and repositioning of thesleeve430 so that thesleeve430 is properly positioned to fit in the anterior chamber angle of the eye for proper deployment of the shunt. Due to these features ofdevice400, some embodiments of the device provide for deploying intraocular shunts without use of an optical apparatus that contacts the eye, preferably without use of any optical apparatus.
• Once the device has been inserted into the eye and theprotrusion431 and thesleeve430 are fitted within the anterior chamber angle of the eye, thehollow shaft404 may be extended from within thesleeve430. Referring now toFIG. 33A which show extension of thehollow shaft404 from within thesleeve430, which is accomplished by partial retraction ofdistal portion401bofhousing401 to withinproximal portion401aof housing401 (FIG. 33A).
• Retraction of thedistal portion401bofhousing401 to withinproximal portion401aofhousing401 is accomplished by an operator continuing to apply force to advancedevice400 after theprotrusion431 and thesleeve430 are fitted within the anterior chamber angle of the eye. The surface area ofprotrusion431 prevents the application of the additional force by the operator from advancingsleeve430 into the sclera434. Rather, the additional force applied by the operator results in engagement ofspring mechanism420 and compression ofspring421 withinspring mechanism420. Compression ofspring420 results in retraction ofdistal portion401bofhousing401 to withinproximal portion401aofhousing401. The amount of retraction ofdistal portion401bofhousing401 to withinproximal portion401aofhousing401 is limited bymember422 that acts as a stopper and limits axial retraction ofdistal portion401bwithinproximal portion401a.
• Retraction ofdistal portion401bofhousing401 to withinproximal portion401aofhousing401 results in extension ofhollow shaft404, which now extends beyond the distal end ofsleeve430 and advances through thesclera442 to an area of lower pressure than the anterior chamber (see e.g.,FIG. 33B).
• InFIG. 33A, a distal end of the shaft is shown to be located within the intra-Tenon's space. Within an eye, there is a membrane known as the conjunctiva, and the region below the conjunctiva is known as the subconjunctival space. Within the subconjunctival space is a membrane known as Tenon's capsule. Below Tenon's capsule there are Tenon's adhesions that connect the Tenon's capsule to the sclera. The space between Tenon's capsule and the sclera where the Tenon's adhesions connect the Tenon's capsule to the sclera is known as the intra-Tenon's space. This figure is exemplary and depicts only one embodiment for a location of lower pressure. It will be appreciated that some embodiments of the device may deploy shunts to various different locations of the eye and are not limited to deploying shunts to the intra-Tenon's space is shown by way of example in this figure. In this configuration, theshunt415 is still completely disposed within theshaft404.
• The distal end ofshaft404 may be beveled to assist in piercing the sclera and advancing the distal end of theshaft404 through the sclera. In this figure, the distal end of theshaft404 is shown to have a double bevel (See alsoFIG. 31B). The double bevel provides an angle at the distal end of theshaft404 such that upon entry of the shaft into intra-Tenon's space, the distal end ofshaft404 will by parallel with Tenon's capsule and will thus not pierce Tenon's capsule and enter the subconjunctival space. This ensures proper deployment of the shunt such that a distal end of theshunt415 is deployed within the intra-Tenon's space, rather than deployment of the distal end of theshunt415 within the subconjunctival space. Changing the angle of the bevel allows for placement ofshunt415 within other areas of lower pressure than the anterior chamber, such as the subconjunctival space. It will be understood thatFIG. 33A-33B is merely one embodiment of whereshunt415 may be placed within the eye, and that some embodiments of the device are not limited to placing shunts within intra-Tenon's space and may be used to place shunts into many other areas of the eye, such as Schlemm's canal, the subconjunctival space, the episcleral vein, or the suprachoroidal space.
• Referring toFIG. 33B, as noted above, retraction ofdistal portion401bofhousing401 to withinproximal portion401aofhousing401 results in extension ofhollow shaft404, which now extends beyond the distal end ofsleeve430 and advances through thesclera442. In accordance with some embodiments, the rigidity of thesleeve430 holdshollow shaft404 in a straight configuration. Upon its exposure from thesleeve430,hollow shaft404 reverts to its pre-bent configuration, which bend minors the angle or arc of the sclera. Such a pre-bend allows thehollow shaft404 to follow the scleral spur down along the sclera in a self-guided manner to the suprachoroidal space. Generally, the bend in thehollow shaft404 will be from about 5° degrees to about 70° degrees.
• Additionally, the flexibility of thehollow shaft404 allows it to continually bend and flex in response to the anatomy as thehollow shaft404 advances from thesleeve430. Thehollow shaft404 is advanced until a distal portion of thehollow shaft404 is within the suprachoroidal space. In this configuration, theshunt415 is still completely disposed within theshaft404. The distal end ofhollow shaft404 may be beveled to assist in piercing the sclera and advancing the distal end of thehollow shaft404 through the sclera.
• At this point, an amount of BSS/steroid or other drug can be optionally injected through the hollow shaft and implant into a lower end of the target space to create a primed space for outflow and to deliver antifibrotic or other drugs to that new drainage space.
• Reference is now made toFIGS. 34A to 34D. After extension ofhollow shaft404 fromsleeve430, theshunt415 may be deployed from thedevice400. Thedeployment mechanism403 is a two-stage system. The first stage is engagement of thepusher component418 and the second stage is retraction of thedistal portion409 ofdeployment mechanism403 to within theproximal portion410 of thedeployment mechanism403. Rotation of therotating portion410aof theproximal portion410 of thedeployment mechanism403 sequentially engages the pusher component and then the retraction component.
• In the first stage of shunt deployment, the pusher component is engaged and the pusher partially deploys the shunt from the deployment device. During the first stage, rotatingportion410aof theproximal portion410 of thedeployment mechanism403 is rotated, resulting in movement ofmembers414aand414balongfirst portions413a1 and413b1 inchannels413aand413b. Since thefirst portion413a1 ofchannel413ais straight and runs perpendicular to the length of therotating portion410a, rotation of rotatingportion410adoes not cause axial movement ofmember414a. Without axial movement ofmember414a, there is no retraction of thedistal portion409 to within theproximal portion410 of thedeployment mechanism403. Since thefirst portion413b1 ofchannel413bruns diagonally along the length of therotating portion410a, upwardly toward a distal end of thedeployment mechanism403, rotation of rotatingportion410acauses axial movement ofmember414btoward a distal end of the device. Axial movement ofmember414btoward a distal end of the device results in forward advancement of thepusher component418 within thehollow shaft404. Such movement ofpusher component418 results in partially deployment of theshunt415 from theshaft404.
• FIGS. 34A-34C show schematics of the deployment mechanism at the end of the first stage of deployment of the shunt from the deployment device.FIGS. 34A-34B show the shaft in a straight configuration, as if it is within the stiff outer sleeve. As is shownFIG. 34A,members414aand414bhave finished traversing alongfirst portions413a1 and413b1 ofchannels413aand413b. Additionally,pusher component418 has advanced within hollow shaft404 (FIG. 34B), and shunt415 has been partially deployed from the hollow shaft404 (FIG. 34C). As is shown inFIG. 34D, a portion of theshunt415 extends beyond an end of theshaft404.
• FIGS. 35A-35B show device400 at the end of the first stage of deployment of theshunt415 fromdevice400 and into theeye440. This figure shows that thedistal portion401bof thehousing401 remains retracted within theproximal portion401aof thehousing401, and that thehollow shaft404 remains extended from thesleeve430. As is shown in these figures,pusher418 has been engaged and, which allowsshunt415 to be deployed from thehollow shaft404. A portion of theshunt415 can extend beyond an end of theshaft404 and be located in the intra-Tenon's space.
• Reference is now made toFIGS. 36A-36D. In the second stage of shunt deployment, the retraction component of deployment mechanism is engaged and the distal portion of the deployment mechanism is retracted to within the proximal portion of the deployment mechanism, thereby completing deployment of the shunt from the deployment device. During the second stage, rotatingportion410aof theproximal portion410 of thedeployment mechanism403 is further rotated, resulting in movement ofmembers414aand414balongsecond portions413a2 and413b2 inchannels413aand413b. Since thesecond portion413b2 ofchannel413bis straight and runs perpendicular to the length of therotating portion410a, rotation of rotatingportion410adoes not cause axial movement ofmember414b. Without axial movement ofmember414b, there is no further advancement ofpusher418. Since thesecond portion413a2 ofchannel413aruns diagonally along the length of therotating portion410a, downwardly toward a proximal end of thedeployment mechanism403, rotation of rotatingportion410acauses axial movement ofmember414atoward a proximal end of the device. Axial movement ofmember414atoward a proximal end of the device results in retraction of thedistal portion409 to within theproximal portion410 of thedeployment mechanism403. Retraction of thedistal portion409, results in retraction of thehollow shaft404. Since theshunt415 abuts thepusher component418, the shunt remains stationary as thehollow shaft404 retracts from around theshunt415. Thehollow shaft404 retracts completely to within thesleeve430 of thedistal portion401bof thehousing401. During both stages of the deployment process, thesleeve430 remains stationary and in a fixed position.
• Referring toFIGS. 36A-36D, which show schematics of the deployment mechanism at the end of the second stage of deployment of the shunt from the deployment device. As is shown inFIG. 36A,members414aand414bhave finished traversing alongsecond portions413a2 and413b2 ofchannels413aand413b. Additionally,distal portion409 has retracted to withinproximal portion410, thus resulting in retraction of thehollow shaft404 to within thesleeve430.FIG. 36A shows the shaft in a straight configuration, after it has been retracted into the stiff outer sleeve.
• FIGS. 36B and 36C show a schematic of thedevice400 in theeye430 after the second stage of deployment has been completed.FIG. 36B shows that thedistal portion401bof thehousing401 remains retracted within theproximal portion401aof thehousing401. As is shown inFIGS. 36B and 36C,shaft404 has withdrawn through the sclera434 to be fully retracted to withinsleeve430. At completion of the second stage of deployment, a distal portion of theshunt415 has been deployed and resides in the intra-Tenon's space (seeFIG. 36B) or in the suprachoroidal space (seeFIG. 36C), a middle portion of theshunt415 spans the sclera, and a proximal portion ofshunt415 has been deployed fromshaft404 yet still resides withinsleeve430. The proximal portion of theshunt415 still abutspusher418.
• Referring toFIG. 36D, in the post-deployment configuration, the deployedindicator419 is visible throughslot406 of thehousing401, providing feedback to the operator that thedeployment mechanism403 has been fully engaged and that thedeployment mechanism403 has completed its second stage of deployment.
• Referring toFIG. 37A-37B, which show schematics of thedevice400 after completion of deployment of theshunt415 from thedevice400 and in to theeye440. After completion of the second stage of the deployment by thedeployment mechanism403, as indicated to the operator by visualization of deployedindicator419 throughslot406 of thehousing401, the operator may pull thedevice400 from theeye440. Backward force by the operator reengagesspring mechanism420 and results in uncoiling of spring421 (FIG. 37A). Uncoiling ofspring421 proceeds as theproximal portion401aofhousing401 is pulled from theeye440. Such action causesdistal portion401bto return to its extended state withinproximal portion401aof housing401 (FIG. 37A). Continued backward force by the operator continues to pull thedevice400 from theeye440. As thedevice400 is continued to be pulled from the eye, thesleeve430 is also pulled backward and the proximal portion of theshunt415 is exposed from within thesleeve430 and resides within theanterior chamber441 of the eye440 (FIG. 37B). The operator continues to apply backward force until thedevice400 is completely withdrawn from theeye440. At this point, in some embodiments, a distal portion of theshunt415 has been deployed and can reside in the suprachoroidal space (seeFIGS. 36C and 37B), a middle portion of theshunt415 spans the sclera, and a proximal portion ofshunt415 has been deployed and resides in the anterior chamber.
Three Stage Deployment Mechanism
• Another embodiment by which thehollow shaft404 may be extended from thesleeve430 involves a deployment mechanism that is a three-stage mechanism. The three-stage mechanism operates similarly to the above described device that uses a spring loaded distal portion and a two-stage deployment mechanism. In the three-stage system, the channels of the deployment mechanism are extended to accommodate the new first stage. The newly added portion of the channels run diagonally upward along the length of the rotating portion toward the proximal end of the deployment mechanism. Axial movement by the members within the channels results in the extension of thehollow shaft404 from thesleeve430. The new first stage replaces the spring loaded distal portion and results in extension of thehollow shaft404 from thesleeve430. The engagement of thepusher component418 becomes the second stage and retraction of thedistal portion409 ofdeployment mechanism403 to within theproximal portion410 of thedeployment mechanism403 becomes the third stage. The second and third stages of the three-stage system are the same as the first and second stages of the two-stage system and operate as described above. Rotation of the rotating portion of the distal portion of the deployment mechanism sequentially extends the hollow shaft from the sleeve, engages the pusher component and then engages the retraction component.
• Referring now toFIGS. 38A-38E, thesleeve505 may include anedge531 at a distal end that provides resistance feedback to an operator upon insertion of thedeployment device500 within aneye532 of a person during delivery of theshunt515. Upon advancement of thedevice500 across ananterior chamber533 of theeye532, thehollow sleeve505 will eventually contact thesclera534, providing resistance feedback to an operator that no further advancement of thedevice500 is necessary. Theedge531 of thesleeve505 prevents theshaft504 from accidentally being pushed too far through thesclera534.
Combinations of Embodiments
• As will be appreciated by one skilled in the art, individual features of some embodiments may be used separately or in any combination. Particularly, it is contemplated that one or more features of the individually described above embodiments may be combined into a single shunt.
INCORPORATION BY REFERENCE
• References and citations to other documents, such as patents, patent applications, patent publications, journals, books, papers, web contents, have been made throughout this disclosure. All such documents are hereby incorporated herein by reference in their entirety for all purposes.
EQUIVALENTS
• The inventions may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The foregoing embodiments are therefore to be considered in all respects illustrative rather than limiting on the inventions described herein.

Claims (27)

What is claimed is:

1. A method of deploying an intraocular shunt into an eye, the method comprising:

inserting into the eye a hollow shaft, having a curved configuration and a less curved configuration, less curved than the curved configuration, and holding an intraocular shunt;

injecting a drug into the eye;

exposing the shunt, out of the shaft along a scleral spur of the eye while the shaft is in the curved configuration along the scleral spur such that the shunt forms a passage with a proximal portion of the shunt residing in an anterior chamber of the eye and a distal portion of the shunt residing in the suprachoroidal space;

withdrawing the shaft, in the less curved configuration, from the eye.

2. The method ofclaim 1, wherein the drug comprises a balanced salt solution, a steroid, or an antifibrotic agent.

3. The method ofclaim 1, wherein the injecting comprises injecting the drug into a suprachoroidal space of the eye.

4. The method ofclaim 1, wherein the injecting comprises injecting the drug into the eye through the hollow shaft and the shunt.

5. The method ofclaim 1, wherein the exposing comprises allowing the shunt to be guided along the scleral spur of the eye.

6. The method ofclaim 1, wherein the eye comprises a cornea, and the inserting comprises inserting the hollow shaft through the cornea.

7. The method ofclaim 1, wherein the eye comprises a corneal limbus, and the inserting comprises inserting the shaft into the eye posterior to the corneal limbus.

8. The method ofclaim 1, wherein inserting the hollow shaft comprises moving at least a portion of the shaft out of a hollow sleeve, such that the hollow shaft changes from the less curved configuration in the sleeve to the curved configuration out of the sleeve.

9. The method ofclaim 1, wherein inserting the hollow shaft comprises forming a curved pathway along a scleral spur.

10. The method ofclaim 1, wherein during the withdrawing, the shaft is withdrawn into a hollow sleeve and changes from the curved configuration to the less curved configuration.

11. The method ofclaim 1, wherein the shunt comprises a pharmaceutical or biological agent deliverable to the eye.

12. The method ofclaim 11, wherein the pharmaceutical or biological agent comprises a coating on a surface of the shunt.

13. The method ofclaim 11, wherein a portion of the shunt is impregnated with the pharmaceutical or biological agent.

14. The method ofclaim 11, wherein the pharmaceutical or biological agent comprises a time-release pharmaceutical or biological agent.

15. A method of deploying an intraocular shunt into an eye, the method comprising:

inserting into the eye a hollow shaft, having a curved configuration and a less curved configuration, less curved than the curved configuration, and holding an intraocular shunt;

injecting a drug into the eye;

exposing the shunt out of the shaft, while the shaft is in the curved configuration, such that the shunt forms a curved passage with a proximal portion of shunt residing in an anterior chamber of the eye and a distal portion of the shunt residing in the suprachoroidal space; and

withdrawing the shaft, in the less curved configuration, from the eye.

16. The method ofclaim 15, wherein the drug comprises a balanced salt solution, a steroid, or an antifibrotic agent.

17. The method ofclaim 15, wherein the injecting comprises injecting the drug into a suprachoroidal space of the eye.

18. The method ofclaim 15, wherein the injecting comprises injecting the drug into the eye through the hollow shaft and the shunt.

19. The method ofclaim 15, wherein the eye comprises a cornea, and the inserting comprises inserting the hollow shaft through the cornea.

20. The method ofclaim 15, wherein the eye comprises a corneal limbus, and the inserting comprises inserting the shaft into the eye posterior to the corneal limbus.

21. The method ofclaim 15, wherein inserting the hollow shaft comprises moving at least a portion of the shaft out of a hollow sleeve, such that the hollow shaft changes from the less curved configuration in the sleeve to the curved configuration out of the sleeve.

22. The method ofclaim 15, wherein inserting the hollow shaft comprises forming a curved pathway along a scleral spur.

23. The method ofclaim 15, wherein during the withdrawing, the shaft is withdrawn into a hollow sleeve and changes from the curved configuration to the less curved configuration.

24. The method ofclaim 15, wherein the shunt comprises a pharmaceutical or biological agent deliverable to the eye.

25. The method ofclaim 24, wherein the pharmaceutical or biological agent comprises a coating on a surface of the shunt.

26. The method ofclaim 24, wherein a portion of the shunt is impregnated with the pharmaceutical or biological agent.

27. The method ofclaim 24, wherein the pharmaceutical or biological agent comprises a time-release pharmaceutical or biological agent.

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