US20100185049A1 - Dome and screw valves for remotely adjustable gastric banding systems - Google Patents

Abstract

An implantable device controls the movement of fluid to an inflatable portion of a gastric band. The implantable device includes a body. The body has an inlet, an outlet and a valve seat positioned between the inlet and the outlet. The body defines a fluid passage from the inlet to the outlet. The implantable device also includes a diaphragm. The diaphragm has one or more edges coupled to the body. The diaphragm is made of an elastomeric material and capable of being moved between a closed position that blocks the valve seat and does not allow the fluid to move from the inlet to the outlet and an open position that does not block the valve seat and allows the fluid to move from the inlet to the outlet.

Description

CROSS REFERENCE TO RELATED APPLICATIONS
• This application is a continuation-in-part of U.S. patent application Ser. No. 12/603,058, filed Oct. 21, 2009, which claims the benefit of U.S. provisional patent application No. 61/107,576, filed Oct. 22, 2008, the entire disclosure of each of these applications are incorporated herein by reference.
FIELD
• The present invention generally relates to medical systems and apparatus and uses thereof for treating obesity and/or obesity-related diseases, and more specifically, relates to dome and screw valves for remotely adjustable gastric banding systems.
BACKGROUND
• Adjustable, gastric banding systems provide an effective and substantially less invasive alternative to gastric bypass surgery and other conventional surgical weight loss procedures. Despite the sustained weight loss of invasive weight loss procedures, such as gastric bypass surgery, it has been recognized that sustained weight loss can also be achieved through a laparoscopically-placed gastric band, for example, the LAP-BAND® (Allergan, Inc., Irvine, Calif.) gastric band or the LAP-BAND AP® (Allergan, Inc., Irvine, Calif.) gastric band. Generally, gastric bands are placed about the cardia, or upper portion, of a patient's stomach forming a stoma that restricts the food's passage into a lower portion of the stomach. When the stoma is of an appropriate size that is restricted by a gastric band, food held in the upper portion of the stomach provides a feeling of satiety or fullness that discourages overeating. Unlike gastric bypass surgery procedures, adjustable gastric banding systems are reversible and require no permanent modification to the gastrointestinal tract.
• Over time, a stoma created by the gastric band may need an adjustment in order to maintain an appropriate size, which is neither too restrictive nor too passive. Prior art gastric banding systems provide a subcutaneous fluid access port connected to an expandable or inflatable portion of the gastric band. By adding fluid to or removing fluid from the inflatable portion by means of a hypodermic needle inserted into the fluid access port, the effective size of the gastric band can be adjusted to provide a tighter or looser constriction.
• It would be desirable to allow for non-invasive adjustment of gastric band constriction, for example, without the use of the hypodermic needle. Thus, remotely adjustable gastric banding systems capable of non-invasive adjustment are desired and described herein.
SUMMARY
• In one example embodiment of the present invention, there is an implantable device that controls the movement of fluid to an inflatable portion of a gastric band. The implantable device includes a body. The body has an inlet, an outlet and a valve seat positioned between the inlet and the outlet. The body defines a fluid passage from the inlet to the outlet.
• The implantable device also includes a diaphragm. The diaphragm has one or more edges coupled to the body. The diaphragm is made of an elastomeric material and capable of being moved between a closed position that blocks the valve seat and does not allow the fluid to move from the inlet to the outlet and an open position that does not block the valve seat and allows the fluid to move from the inlet to the outlet.
• The implantable device also includes an actuator. The actuator is configured to apply a force on the diaphragm causing the diaphragm to move from the closed position to the open position. The implantable device also includes a microcontroller coupled to the actuator, the microcontroller configured to receive a telemetric signal from a remote transmitter and control the actuator based on the telemetric signal.
• In another example embodiment of the present invention, there is an implantable device that controls the movement of fluid to an inflatable portion of a gastric band. The implantable device includes a body. The body has an inlet, an outlet and a valve seat. The body defines a fluid passage from the inlet to the outlet.
• The implantable device also includes a valve seal. The valve seal has one or more edges coupled to the body. The valve seal is made of an elastomeric material and is capable of being moved between an open position that does not block the valve seat and allows the fluid to move from the inlet to the outlet and a closed position that blocks the valve seat and does not allow the fluid to move from the inlet to the outlet.
• The implantable device also includes an actuator. The actuator is positioned within the body. The actuator has an actuator body defining a threaded screw hole and a screw positioned within the threaded screw hole. The screw is configured to apply a force on the valve seal causing the valve seal to move from the open position to the closed position when the actuator receives a telemetric signal from an implantable microcontroller. A first telemetric signal may be used to move the valve seal from the open position to the closed position and a second telemetric signal may be used to move the valve seal from the closed position to the open position.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 illustrates a perspective view of a remotely adjustable gastric banding system according to an embodiment of the present invention.
• FIG. 2 illustrates an example configuration of the internal components of the high precision pump unit illustrated inFIG. 1 according to an embodiment of the present invention.
• FIGS. 3A and 3B illustrate the filling and draining, respectively, of a gastric band using the systems described herein according to an embodiment of the present invention.
• FIGS. 4A and 4B illustrate cross-sectional views of an exemplary valve in a closed position and an open position according to an embodiment of the present invention.
• FIGS. 5A and 5B illustrate cross-sectional views of an exemplary dome valve in a closed position and an open position according to an embodiment of the present invention.
• FIGS. 6A and 6B illustrate cross-sectional views of an exemplary screw valve in a closed position and an open position according to an embodiment of the present invention.
• FIGS. 7A,7B and7C illustrate side views of examples of the coupling mechanism illustrated inFIGS. 6A and 6B according to various embodiments of the present invention.
• FIG. 8 is a flow chart of a method of controlling a dome valve according to an embodiment of the present invention.
• FIG. 9 is a flow chart of a method of controlling a screw valve according to an embodiment of the present invention.
DETAILED DESCRIPTION
• The present invention generally provides remotely adjustable gastric banding systems, for example, for treatment of obesity and obesity related conditions, as well as systems for controlling inflation of a gastric banding system.
• Remotely adjustable gastric banding systems, otherwise referred to as a remotely adjustable band (RAB), include one or more medical devices, or a system, which allows a healthcare worker to adjust a gastric band without requiring a hypodermic needle to be inserted into an implanted access port. The RAB may use a remote transmitter to send radiofrequency signals or telemetric signals for powering and communicating with an implanted device of the RAB. The implanted device can fill or drain a gastric band of the RAB as requested by the healthcare worker via the remote transmitter. In between filling and draining adjustments to the gastric band, the volume of fluid contained in the gastric band ideally remains unchanged.
• In one embodiment, a dome valve is used to pass and block fluid. The dome valve has an actuator that can adjust an elastomeric diaphragm (e.g., a valve seal) to an open or closed position. The dome valve can be used safely during magnetic resonance imaging (MRI) since the dome valve does not have a significant amount of ferromagnetic material. The elastomeric diaphragm is also inexpensive and robust.
• In another embodiment, a screw valve is used to pass and block fluid. The screw valve has a screw that can adjust a valve seal to multiple precise positions, not just fully open or fully closed. The screw valve can be used in a high pressure environment since no force is required to maintain a position and because the screw can be driven to create a tight seal.
• FIG. 1 illustrates a perspective view of a remotely adjustablegastric banding system100 according to an embodiment of the present invention. Thegastric banding system100 includes agastric band102, areservoir104, a highprecision pump unit106, aremote transmitter108 andtubing110. The skin122 of a human illustrates a separation between implantable components and non-implantable components. As illustrated, the remote transmitter108 (e.g., a remote controller unit) is non-implantable, whereas thegastric band102, thereservoir104, the highprecision pump unit106, and thetubing110 are implantable (e.g., an implantable device), and can be implanted in the human using conventional surgical techniques. The highprecision pump unit106 can be used to replace or complement a conventional access port for adjusting inflation or deflation of thegastric band102. In some embodiments, the system includes anoverride port212 which can be used, for example, with ahypodermic needle112, to fill and drain thegastric band102.
• The highprecision pump unit106 is connected to thereservoir104 and thegastric band102 via thetubing110, and can move precisely metered volumes of fluid (e.g., saline) in or out of thegastric band102. Moving the fluid into thegastric band102 causes inflation of at least one bladder, or an inflatable portion114 (e.g., inflatable member) and constricts around the cardia, or upper portion of the stomach, forming a stoma that restricts the passage of food into a lower portion of the stomach. This stoma can provide a patient with a sensation of satiety or fullness that discourages overeating. In contrast, moving the fluid out of theinflatable portion114 of thegastric band102 reduces the pressure around the cardia and allows the stoma to be at least partially released and allows the human to regain a hunger sensation.
• The highprecision pump unit106 is implanted within a patient, and therefore, is non-biodegradable. The encasement or housing of the highprecision pump unit106 may be non-hermetically sealed or hermetically sealed from the in situ environment (e.g., undisturbed environment) in the patient and formed at least partially of any rugged plastic material including, polypropylene, cyclicolephin co-polymer, nylon, and other compatible polymers and the like or at least partially formed of a non-radioopaque metal. The housing has a smooth exterior shape, with no jagged edges, to minimize foreign body response and tissue irritation. The highprecision pump unit106 is also sterilizable, in one embodiment, dry heat sterilizable before implantation.
• Thereservoir104 may be a soft, collapsible balloon made of a biocompatible polymer material, for example, silicone, which holds a reserve of a biocompatible fluid, for example, saline, to allow for adjustments in the size of thegastric band102. In one embodiment, thereservoir104 is fully collapsible and can contain the extra fluid required to increase the volume of thegastric band102 to therapeutic levels. Further, thereservoir104 also may have excess capacity so thegastric band102 may be fully drained into it without thereservoir104 being filled beyond its maximum capacity.
• Thereservoir104 may represent one or both of a source reservoir and a drain reservoir, where the source reservoir provides fluid to thegastric band102, and the drain reservoir receives fluid from thegastric band102.
• The fluids used within the systems of the present invention may include any fluid that is biocompatible. The fluid has no adverse effect on the patient in the unlikely event that a leak emanates from the system. The fluid can simply be water or any biocompatible polymer oil such as caster oil. In an example embodiment, the fluid is, saline.
• Thetubing110 is any biocompatible flexible tubing that does not degrade in vivo (e.g., within the human). Thetubing110 is configured to withstand hydraulic pressure up to about 30 psi (about 206 kPa) without leakage. This hydraulic pressure tolerance is true of the entire fluid path of the systems described herein. Although the systems described herein do not generally leak, if they do, fluid is not lost at a rate greater than about 0.2 cc/yr, or about 0.1 cc/yr.
• Other biocompatible and biostable polymers which are useful for forming thereservoir104 and thetubing110 include: polyolefins, polyisobutylene and ethylene-alphaolefin copolymers; acrylic polymers and copolymers, ethylene-co-vinylacetate, polybutylmethacrylate, vinyl halide polymers and copolymers, such as polyvinyl chloride; polyvinyl ethers, such as polyvinyl methyl ether; polyvinylidene halides, such as polyvinylidene fluoride and polyvinylidene chloride; polyacrylonitrile, polyvinyl ketones; polyvinyl aromatics, such as polystyrene, polyvinyl esters, such as polyvinyl acetate; copolymers of vinyl monomers with each other and olefins, such as ethylene-methyl methacrylate copolymers, acrylonitrile-styrene copolymers, ABS resins, and ethylene-vinyl acetate copolymers; polyamides, such as Nylon 66 and polycaprolactam; alkyd resins; polycarbonates; polyoxymethylenes; polyimides; polyethers; epoxy resins, polyurethanes; rayon; rayon-triacetate; cellulose, cellulose acetate, cellulose butyrate; cellulose acetate butyrate; cellophane; cellulose nitrate; cellulose propionate; cellulose ethers; and carboxymethyl cellulose.
• The systems and apparatus described herein further include the remote transmitter108 (e.g., a remote controller unit), which provides access to system data and functions, and can be an external, handheld, reusable battery-powered device. Theremote transmitter108 can be made of any rugged plastic material including polypropylene, cyclicolephin co-polymer, nylon, and other compatible polymers and the like. Theremote transmitter108 is not implanted within the patient so hermetic sealing of the unit is not required. However, in one embodiment, theremote transmitter108 is at least water resistant, if not waterproof, and can be cleaned using standard hospital disinfectants without damage to the unit.
• Further, theremote transmitter108 has a user interface including at least onedisplay116 and at least oneuser input118. In some example embodiments, thedisplay116 and theuser input118 are combined in the form of a touch screen with a color display. In other embodiments, the display is grayscale. Theremote transmitter108 permits a clinician or a medical technician to navigate through menu driven screens used for data entry, data collection, and controlling the highprecision pump unit106.
• Theremote transmitter108 is capable of communicating with the highprecision pump unit106. “Capable of communicating” as used herein refers to the remote controller's ability to establish communications with the highprecision pump unit106 yet still have the ability to break communication and the systems described herein still function. To establish communication, in one example embodiment, once theremote transmitter108 is initialized, thedisplay116 shows a searching query for a nearby highprecision pump unit106. As theremote transmitter108 is brought into range of the highprecision pump unit106, a symbol displays the strength of the communication link. Once stable communications have been acquired, thedisplay116 shows the serial number of the system so a clinician can verify they have the appropriate patient records in hand. If the patient requires a tightening of thegastric band102, the clinician can enter the amount of the desired volume increase. Theremote transmitter108 can also display the current volume within thegastric band102 and indicate the new volume as thegastric band102 fills. Thedisplay116 can also indicate desired and actual volumes during draining of thegastric band102.
• To verify the appropriate adjustment has been made to the system, the clinician can set theremote transmitter108 into a pressure monitor mode and request that the patient drink water. Thedisplay116 shows a real time graph of the pressure measured within thegastric band102. This diagnostic tool may show higher pressures and warning messages if thegastric band102 has been over-tightened.
• Theremote transmitter108 can synchronize and charge when coupled with a charging cradle or docking station. This docking station provides the ability to recharge a rechargeable battery of theremote transmitter108 and provides a link to download information to a personal computer such as the adjustment history of a patient. Other data that can be stored on theremote transmitter108 and downloaded from the highprecision pump unit106 includes, but is not limited to serial number, gastric band size, patient information, firmware version and patient adjustment history. This data can be downloaded directly to a patient tracking database for easy tracking.
• Any data stored on theremote transmitter108 or within the highprecision pump unit106 can be electronically secured. In other words, security measures can be put in place to keep the data confidential, including communication between the highprecision pump unit106 and theremote transmitter108. Security measures can include computer generated algorithms that prevent intrusion by outside parties.
• The highprecision pump unit106 can contain a micro-fluidic pump with active valves. In such an embodiment, the highprecision pump unit106 is a passive device that can only be powered by theremote transmitter108 when it is in close proximity. For example, in one example embodiment, theremote transmitter108 may be configured to power and communicate with the highprecision pump unit106 at any distance less than about 8 inches, in one embodiment less than about 4 inches (about 10.2 cm) of tissue plus about 4 inches of air, and in another embodiment about 2 inches (about 5.1 cm) of air. Power and communications can be tailored to transmit over longer distances or can be tailored to have theremote transmitter108 placed on the skin adjacent to the highprecision pump unit106.
• Further, theremote transmitter108 can provide an inductive power and telemetric control through atransmission124 to the highprecision pump unit106. Theremote transmitter108 may be configured to provide continuous power to the highprecision pump unit106. A dedicated microcontroller within theremote transmitter108 monitors the amount of power that is transmitted. Further still, a power management system may be implemented to optimize energy transmission between theremote transmitter108 and the highprecision pump unit106 relative to their separation distance. For example, the power transmission may automatically decrease as theremote transmitter108 is closer to the highprecision pump unit106, and may be increased as the distance is increased. This minimizes wasted energy, and energy exposure to the patient.
• The systems and apparatus described herein use common surgical techniques to place the components in their respective positions within a patient. The surgical techniques may be identical or similar to those used in the placement of conventional gastric banding systems. For example, thegastric band102 may be placed around the stomach using laparoscopic techniques, as known to those of skill in the art. Like a conventional access port, the highprecision pump unit106 may be sutured onto the rectus muscle sheath or any other conveniently accessible muscle. In order to achieve a secure attachment of the highprecision pump unit106, the unit shall be sutured to the rectus muscle and remain securely attached for forces below about 6 lbf, in one embodiment below about 3 lbf (13.3 N). Thetubing110 from the highprecision pump unit106 passes through the rectus muscle into the peritoneal cavity in the same manner as the tubing of a conventional access port.
• The systems and apparatus of the present invention further allow for a remotely controlled adjustment without needles, non-invasively, by using theremote transmitter108. Also, should theremote transmitter108 be unavailable, damaged, out of power, or in the even of an emergency, an adjustment of thegastric band102 can be performed invasively using a needle. By using theoverride port212, a clinician can choose to use thehypodermic needle112, a standard needle, or a syringe for adjustments. If any of the electronics associated with the systems and apparatus described herein become inoperable, theoverride port212 can be used to add or remove fluid from thegastric band102. Theoverride port212 and thehypodermic needle112 can always be used to adjust thegastric band102.
• FIG. 2 illustrates an example configuration of the internal components of the highprecision pump unit106 illustrated inFIG. 1 according to an embodiment of the present invention. The housing of the highprecision pump unit106 has an internal volume of between about 0.75 in³to about 1.6 in³. Exemplary internal features of the highprecision pump unit106 that fit within the housing include afirst valve202, asecond valve204, apump206, a pressure/flow sensor208, anelectronics board210 including anantenna211, and theoverride port212. The internal components of the highprecision pump unit106 can be arranged in any fashion appropriate for delivering and removing precise amounts of fluid from thegastric band102 and thereservoir104.
• Thepump206 can be actively or passively driven. If thepump206 is actively driven, a local power source such as a battery (not illustrated) is provided to drive thepump206. If thepump206 is passively driven, it may be inductively powered by a device external to the highprecision pump unit106. In an exemplary configuration, thepump206 is passively driven through inductive power from theremote transmitter108.
• In one example embodiment, thepump206 is an inductively powered, electrically driven, positive displacement piezoelectric pump. Thepump206 provides a means to move fluid into thegastric band102.
• Thepump206 can move fluid from thereservoir104 to thegastric band102 at rates higher than about 0.5 cc/min, for example, higher than about 1 cc/min for band pressures less than about 20 psi (about 138 kPa) relative to the reservoir pressure. Alternatively, fluid can be drained from thegastric band102 to thereservoir104 at rates higher than about 0.5 cc/min, for example, higher than about 1 cc/min for band pressures above about 0.2 psi (about 1.38 kPa).
• Thefirst valve202 and thesecond valve204, illustrated inFIG. 2, can be any valve known in the art to allow precise delivery of fluid and precise flow rates therethrough. In one embodiment, thefirst valve202 and thesecond valve204 only allow fluid to move in one direction, therefore, the two valves are situated in parallel with the highprecision pump unit106 allowing fluid to drain back from thegastric band102. Further, thefirst valve202 and thesecond valve204 should have a precision orifice that restricts the flow rate to a well-characterized, precise amount.
• Thegastric banding system100 may further comprise at least one flow orpressure sensor208 disposed, for example, within or adjacent to the highprecision pump unit106. In an exemplary embodiment, two pressure sensors are situated within the fluid pathway between thefirst valve202 and thesecond valve204 and thegastric band102. During a no-flow condition, both of the pressure sensors may be used to measure pressure thereby providing the benefits of redundancy and averaging.
• For example, sensing or measuring the pressure within the fluid pathway of thegastric banding system100 provides diagnostic uses. A clinician can measure pressure while a patient drinks water, recording and analyzing resulting pressure fluctuations which can help determine if thegastric band102 is too restrictive. Whether thegastric band102 is too restrictive can also be confirmed by the patient's response (generally discomfort) upon drinking the water, and can then be appropriately adjusted. Further, sensing or measuring pressure in thegastric banding system100 can be useful in diagnosing system leaks or obstructions. For example, if the pressure consistently drops over an extended period of time, the clinician can diagnose a leak within the system and plan for an appropriate treatment to fix the problem. In contrast, if there is an obstruction within the system with a sustained pressure rise over time, the clinician can diagnose an obstruction within the system and plan for an appropriate treatment to fix the problem.
• Theoverride port212, as illustrated inFIGS. 1 and 2, is an optional feature of some of the embodiments of the present invention. Theoverride port212 can be manufactured from a metal or a non-radioopaque material and is accessible by insertion of the hypodermic needle112 (inFIG. 1) through a self-sealing septum214 (inFIG. 2). Theoverride port212 allows a clinician to use thehypodermic needle112 or a standard syringe to fill or drain thegastric band102. Further, theoverride port212 may be located on thedistal end216 of the highprecision pump unit106, for example, at a position substantially opposite from theproximal end218 where thetubing220 extends from the highprecision pump unit106. This placement of theoverride port212 thereby reduces possible occurrences of a needle damaging thetubing220. Anextension body222 emanating from the highprecision pump unit106 further protects thetubing220 from accidental needle sticks.
• The highprecision pump unit106 can be a passive device which may be entirely controlled and powered by theremote transmitter108. Theantenna211 on theelectronics board210 is housed within the highprecision pump unit106 and theremote transmitter108 is coupled to allow thetransmission124 of signals and power through the skin122 (as illustrated inFIG. 1). The power issued from theremote transmitter108 is continually monitored by a dedicated microprocessor to ensure that power transmission is minimized to the lowest level required for operation. To minimize thetransmission124 of power and to optimize thetransmission124 of command communication, the highprecision pump unit106 and theremote transmitter108 have a channel frequency dedicated to command communication and a separate channel frequency dedicated to power transmission. The command communication can be configured, for example, to take place at about 402-406 MHz while the power transmission, for example, takes place at about 400 kHz. This command communication adheres to the frequency and power standards set by the Medical Implant Communications Service. To ensure accuracy, communication and control commands are verified by error check algorithms prior to data reporting or command implementation.
• A portion of theelectronics board210 within the highprecision pump unit106 is devoted to conditioning and managing the power received at theantenna211 or from a local battery. Communication electronics manage the bidirectional transmissions with timing verification and error checking. Controller circuits of theelectronics board210 send commands to thefirst valve202, thesecond valve204, thepump206, and the pressure/flow sensor208 and receive data back from the pressure/flow sensor208. Theelectronics board210 can be encased in a biocompatible sealant if further protection, or redundant protection, is necessary.
• In one example embodiment, the systems and apparatus described herein are configured and structured to be compatible with MRI, or MRI safe, at, for example 1.5 T. In the exemplary embodiment shown, the highprecision pump unit106 is entirely inductively powered. The systems utilize no permanent magnets, no long metallic wires or leads, and a minimal or negligible amount of ferrous or ferromagnetic material. The systems are substantially free or contain substantially no ferromagnetic materials. Substantially no ferromagnetic materials refers to materials containing less than about 5%, in one embodiment, less than about 1% or 0.1% (w/w) of ferromagnetic material. The resulting systems are thus MRI safe given standard specifications regulating translational and rotational attraction, MRI heating, and imaging artifacts. In one embodiment, all materials selected for the systems are selected to be compatible and safe in an MRI environment.
• Further, the inductive powering of the highprecision pump unit106 requires that energy be passed through body tissue. Since the body tissue absorbs a small amount of the energy passing through it, the heating of the tissue can be proportional to the total energy transferred. To ensure that the systems meet standards to minimize tissue heating (below 2° C. above body temperature per ISO 45652), the systems described herein have been designed to use very little power to move the fluid within the system and do not cause excessive heating of the patient's tissue.
• The pressure/flow sensor208 can monitor pressure inside thegastric band102 as needed. Using theremote transmitter108 to communicate with the highprecision pump unit106, a clinician can monitor pressure inside thegastric band102, for example, in “real time” during an adjustment of the constriction within thegastric band102. This will allow the clinician to observe the response of thegastric band102 to a patient's adjustment. This may permit a new modality for thegastric band102 adjustment management to monitor pressure as well as volume during an adjustment. With these new pressure sensing capabilities, the clinician can make a determination of whether there is a leak within the system (e.g., zero pressure reading) or whether there is an obstruction in the system (e.g., prolonged pressure rise).
• In an example embodiment, the highprecision pump unit106 includes a first fluid line including a first pump for passing fluid in a first direction and a second fluid line in parallel with the first fluid line including a first valve and a second pump for passing fluid in an opposing direction. In another example embodiment, the second pump is not needed because thegastric band102 provides enough pressure the move the fluid to thereservoir104. The parallel line configuration allows for filling and draining of thegastric band102 with a minimal number of components and minimal complexity.
• The systems and apparatus described herein can achieve at least one of the following features. The total time required to complete a fill or drain of thegastric band102 does not exceed about 10 minutes, and in one embodiment, about 5 minutes. The systems are able to adjust the volume in thegastric band102 accurately to within about 0.1 cc or about 10%, whichever is greater. The pressure/flow sensor208 has a resolution between about 0.010 psi to about 0.025 psi, and in one embodiment, about 0.019 psi (about 130 Pa).
• In one example embodiment of the present invention, components of the systems can be replaced without replacing the entire system and subjecting patients to overly invasive surgeries to replace entire systems when a single component is defective or damaged. For example, if the highprecision pump unit106 becomes damaged, it can be replaced independently of other components. Alternatively, if thegastric band102 becomes damaged, it can be replaced independently of other components. The same is true of thetubing110 and thereservoir104. Although components can be disconnected for single part replacement, components shall not become dislodged from thetubing110 for tubing pull-off forces less than about 10 lbf, and in one embodiment, less than about 5 lbf (22.2 N).
• The systems described herein meet at least one safety specification. For example, in the event of any failure of the systems, either no change in thegastric band102 tightness or a loosening of thegastric band102 results. Further, the highprecision pump unit106 is biocompatible for long term implantation and theremote transmitter108 is biocompatible for transient use both per ISO 10993. The systems are designed to have no significant interaction or interference with other electronics in any of the following modalities: implantable energy sources such as defibrillators and pacemakers; internal energy sources such as electrosurgical instruments; external energy sources such as ultrasound, x-rays and defibrillators; and radiofrequency signals such as pacemaker programmers and neurostimulators.
Example 1Implantation of a Gastric Band System
• A 40 year old female is diagnosed by her clinician as obese, weighing 510 lbs. The clinician suggests to the patient that she consider thegastric banding system100 according to the present invention. She agrees and undergoes the implantation procedure. Thegastric band102 is implanted around her cardia thereby creating a stoma. The highprecision pump unit106 is sutured onto the rectus muscle sheath and thetubing110 and thereservoir104 passes through the rectus muscle into the peritoneal cavity and connects to thegastric band102. Thegastric banding system100 comes pre-filled, so there is no need for the clinician to fill thegastric banding system100 during the surgical procedure. The patient is sutured and sent to recovery.
Example 2Adjustment of a Gastric Band System
• The female patient of Example 1, after the completion of the surgical implantation, has hergastric band system100 properly adjusted by her clinician. The clinician holds theremote transmitter108 to the skin122 adjacent to the rectus muscle where the highprecision pump unit106 is located and initiates communication between the devices. An initial pressure of zero is displayed for thegastric band102 as no fluid has been added to thegastric band102. The clinician begins to fill thegastric band102 using saline housed within thereservoir104 at a rate of about 1 cc/min and the entire filling takes less than about 5 minutes.
• After filling, to about 10 psi, the patient is instructed to drink a glass of water in order to properly assess the proper inflation pressure of thegastric band102 to ensure it has not been over inflated. Upon confirmation that thegastric band102 is properly inflated, the procedure is completed and the patient returns to her normal life.
• The patient instantly notices that she is much less hungry than she previously had been and is consistently consuming less food as her appetite has been decreased. She returns to her clinician's office for a follow-up visit three months after her implantation and initial gastric band filling and she has lost 20 pounds. A year later, she has lost nearly 60 lbs.
• Thegastric banding system100 generally functions as follows. When a clinician uses theremote transmitter108 to adjust thegastric band102, the highprecision pump unit106 initiates a sequence of events to move a precise amount of fluid in the desired direction, where the filling is discussed inFIG. 3A and the draining is discussed inFIG. 3B.
• FIG. 3A illustrates the filling of thegastric band102 according to an embodiment of the present invention. Just before pumping is initiated, thesecond valve204, in line with thepump206, is opened. Thepump206 creates a differential pressure to draw fluid out of thereservoir104 and into thegastric band102. Thefirst valve202 and the pressure/flow sensor208 are closed or not engaged. Thereservoir104 is collapsible and does not impede the outward flow of fluid. Further, thereservoir104 is sized such that when filled to the maximum recommended fill volume, there is a slight vacuum therein. Once the proper amount of fluid has been transferred from thereservoir104 to thegastric band102, the electronics board210 (or circuitry thereon) shuts off thepump206 and closes thesecond valve204. Thegastric band102 now assumes the new higher pressure and fluid.
• Referring toFIG. 3B, if the clinician decides to there is a need to loosen thegastric band102, fluid is released from thegastric band102 and returned to thereservoir104. Once the highprecision pump unit106 receives a drain command from theremote transmitter108, thefirst valve202 behind the pressure/flow sensor208 opens. The fluid is transferred from thegastric band102 through the pressure/flow sensor208 and thefirst valve202 and into thereservoir104. The amount of fluid released from thegastric band102 can be monitored and determined by the pressure/flow sensor208. Once the correct volume of fluid has been transferred, thefirst valve202 is closed. With both thefirst valve202 and thesecond valve204 closed, the volume in thegastric band102 is maintained and the pressure in thegastric band102 can be measured accurately using the pressure/flow sensor208.
• When compared to conventional gastric banding systems having standard access ports which exclusively require syringe access (as oppose to being optional), the presently described systems and apparatus offer several benefits. First, the conventional access ports are located under a thick layer of fatty tissue, which is generally the case as the devices are generally used to treat obesity, and the access port can be difficult to locate. The present systems reduce or eliminate the need for (or to locate) the access port, as the use of theremote transmitter108 removes the need for adjustment using thehypodermic needle112.
• Secondly, when accessing the access port in conventional systems, the ambiguity on its location may lead to damage by accidentally puncturing thetubing110 which connects theaccess port212 to thegastric band102. This can require a revision surgery in order to repair the puncturedtubing110. Further, when a conventional access port cannot be located by palpation, x-ray imaging may be required to guide a needle into the access port. Such imaging practices put a patient at risk for x-ray radiation exposure. The present systems and apparatus remove the need for these unnecessary procedures and save the patient from x-ray radiation exposure. The present systems and apparatus are compatible with magnetic resonance imaging (MRI), which is much safer for a patient.
• In the unlikely event that theoverride port212 of the present invention needs to be used, theoverride port212 may be located away from the tubing connection to thegastric band102 to reduce the potential for tubing needle sticks. The highprecision pump unit106 has geometry and a rigid case that can be structured to facilitate the user in locating theoverride port212 when needed.
• FIGS. 4A and 4B illustrate cross-sectional views of anexemplary valve400 in a closed position (FIG. 4A) and an open position (FIG. 4B) according to an embodiment of the present invention. Thevalve400 may be used in place of one or both of thefirst valve202 and thesecond valve204.
• Referring toFIG. 4A, thevalve400 is biased in a closed position, for example, by aspring preload force402 acting on aseal404, for example, aflexible silicone seal404. For example, thespring preload force402 pushes theflexible silicone seal404 into sealing engagement with avalve seat406. When thevalve400 is sealed as shown inFIG. 4A, fluid cannot pass from avalve inlet408 to avalve outlet410.
• Now referring toFIG. 4B, when fluid flow is desired, a signal is sent to a valve actuator (not shown), which removes thespring preload force402 and permits theflexible silicone seal404 to relax or move upward into an open position, out of sealing engagement with thevalve seat406. The fluid is then free to flow from thevalve inlet408 to thevalve outlet410 until thevalve400 is closed, for example, by reapplication of thespring preload force402.
• FIGS. 5A and 5B illustrate cross-sectional views of anexemplary dome valve500 in a closed position (FIG. 5A) and an open position (FIG. 5B) according to an embodiment of the invention. In one embodiment, thedome valve500 is an implantable device that controls the movement of fluid to theinflatable portion114 of thegastric band102. Thedome valve500 may be used in place of one or both offirst valve202 and thesecond valve204.
• Thedome valve500 is designed to be implanted into a patient, and thus may be referred to as a micro valve. In an embodiment, thedome valve500 has a length of about 15 mm (e.g., 10-25 mm range) and an about 10 mm outer, diameter (e.g., 7-15 mm range). In one embodiment, thedome valve500 is a radially symmetric shape (e.g., disk, tube, rod, etc.). However, thedome valve500 can be any shape (e.g., circular, square, rectangular, etc). Thedome valve500 can include abody560, anactuator505, acap510, and adiaphragm520.
• Thebody560 has aninlet component530, anoutlet component535, and abottom component550. Theinlet component530, theoutlet component535, and thebottom component550 have been identified for illustrative purposes and may not be separate components from thebody560. Aninlet540, which is a fluid entrance into thebody560, is defined between theinlet component530 and thebottom component550. Anoutlet545, which is a fluid exit from thebody560, is defined between theoutlet component535 and thebottom component550.
• Theinlet component530 and thebottom component550 form avalve seat570. Thevalve seat570 can be the surfaces (e.g., the tips) of theinlet component530 and thebottom component550 which provide sealing when thediaphragm520 is placed against and in contact with theinlet component530 and thebottom component550. In one embodiment, the vertical column of theinlet component530 and thebottom component550 define thevalve seat570. The vertical columns may be short segments (e.g., 1.5 mm) of plastic or metal tubing (e.g., stainless steel).
• Theactuator505 is configured to apply a force (e.g., stress) on thecap510 causing thediagraph520 to move from the closed position (FIG. 5A) to the open position (FIG. 5B) when theactuator505 receives a telemetric signal124 (e.g., electrical energy) from theremote transmitter108. The force includes a smallerdownward force555 to keep thevalve500 in a closed position (FIG. 5A) and a largerdownward force565 to keep thevalve500 in an open position (FIG. 5B). In an embodiment, thesmaller force555 is less than 10 newtons. In an embodiment, thelarger force565 is between 10-100 newtons. In another embodiment, thelarger force565 is between 15-45 newtons.
• FIG. 5A illustrates theactuator505 applying the smaller force555 (e.g., 0 newtons, little or no downward force, a reduced in force, a de-energized state), which is low enough to keep thevalve500 in the closed position. In particular, when theactuator505 applies thesmaller force555, thecap510 receives little or no downward force on cap edges515. Since the cap edges515 are adjacent to the diaphragm edges525, the diaphragm edges525 also receive little or no downward force. As such, thediaphragm center527 of thediaphragm520 remains sitting on (or relaxed onto) thevalve seat570, blocking fluid from flowing from theinlet540 to theoutlet545.
• FIG. 5B illustrates theactuator505 applying a large force565 (e.g., an energized state) that compresses (e.g., squeezes) the diaphragm edges525 between thecap510 and thebody560. Thelarge force565 is great enough that the material on the diaphragm edges525 is compressed, with thecap510 blockingdiaphragm edges525 from expanding outward, the diaphragm is expanded inward such that thediaphragm center527 is moved up off thevalve seat570 due to a build up of material. This opens a passage from theinlet540 to theoutlet545 and permitting fluid flow in thevalve500 as shown byfluid flow indicators575. When a downward force is applied, thediaphragm center527 moves in a substantially opposite direction to the downward force.
• Theactuator505 can take many forms (e.g., solenoids, stepper motors, piezoelectric actuator, electroactive polymer, etc.) as dictated by the specific application. In one embodiment of the RAB, theactuator505 is a piezoelectric actuator. In another embodiment, theactuator505 is an electroactive polymer.
• Thecap510 may be positioned between thediaphragm520 and theactuator505. Thecap510 has one or more cap edges515 (e.g., cap ends). The cap edges515 direct thesmall force555 and thelarge force565 from theactuator505 to thediaphragm520. In one embodiment, thecap510 is part of theactuator505.
• Thediaphragm520, which may be referred to as a valve seal, is positioned between thecap510 and thebody560. Thediaphragm520 has a diaphragm center527 (e.g., a body) and one or more diaphragm edges525 (e.g., ends of the diaphragm520) coupled to thebody560.
• The diaphragm520 (e.g., valve seal) has an open position (FIG. 5B) and a closed position (FIG. 5A). When thediaphragm520 is in the open position, thediaphragm520 does not block thevalve seat570 and therefore allows the fluid to move from theinlet540 to theoutlet545. Conversely, when thediaphragm520 is in a closed position, thediaphragm520 blocks thevalve seat570 and does not allow the fluid to move from theinlet540 to theoutlet545.
• In one embodiment, thediaphragm520 is made of an elastomeric material. The elastomeric material includes silicon and any other material that is stretchy like a rubber band. For example, the elastomeric material includes flexible materials, naturally occurring elastic substances (e.g., natural rubber), and synthetically produced substances (e.g., silicon, butyl rubber, neoprene).
• The elastomeric material can be stretched across thevalve seat570 to provide a seal and can buckle to create agap526 above thevalve seat570. In an embodiment, thegap526 below thediaphragm520 is substantially less than 1 mm off thevalve seat570. In one embodiment, thegap526 is about 0.03 mm. In one embodiment, the range for thegap526 is between about 0.01 mm to about 0.25 mm. In another embodiment, the range for thegap526 is between about 0.01 mm to about 0.10 mm.
• In one embodiment, thediaphragm520 is circular, although any shape is possible (e.g., a thin strip, rectangular, etc).
• Thedome valve500 has numerous advantages over conventional valves. Thedome valve500 contains no ferromagnetic material as is commonly used in conventional valves (e.g., solenoid valves). As a result, thedome valve500 advantageously can be safely used in conjunction with magnetic resonance imaging (MRI) scanning.
• Additionally, thedome valve500 advantageously is not concentric with the diaphragm, unlike conventional valves which have a concentric shaped seal which results in high susceptibility to leakage and contamination to the moving parts of the valve.
• Advantageously, both thediaphragm520 and thecap510 restrict fluid from contacting the moving valve components, such as theactuator505. This allows thedome valve500 to be used in a system where the fluid is highly corrosive to the moving parts and can be used where the moving parts rub and create contaminants that must be keep free from the fluid, because thedome valve500 protects the moving valve components from contamination.
• Dome valve500 advantageously can be inexpensively manufactured, due partly to the mechanical linkage, while still being robust and efficient. Opening thevalve500 requires very little stroke or travel from theactuator505 to produce a suitably large upward deflection in thediaphragm520. In contrast, conventional valves use energy inefficient methods such as forming a seal for a valve by heating a membrane comprised of two materials with different coefficients of linear thermal expansion.
• Also, thedome valve500 achieves a low leak/leakage rate when in the closed position (e.g., closed/sealed tightly) compared to conventional valves and achieves a high flow rate when in the open position. Further, thedome valve500 minimizes the space required for the implanted device because thedome valve500 can be smaller than other implantable devices.
• FIGS. 6A and 6B illustrate cross-sectional views of anexemplary screw valve600 in a closed position (FIG. 6A) and an open position (FIG. 6B) according to an embodiment of the present invention. Thescrew valve600 is part of the RAB and may be used in place of one or both of thefirst valve202 and thesecond valve204. Thescrew valve600 is designed small enough to be implanted into a patient, and thus may be referred to as a micro valve. In an embodiment, thescrew valve600 has a length of approximately 30-50 mm and an about 10 mm outer diameter (e.g., 7-15 mm range). In comparison to thedome valve500 embodiment discussed above (10-25 mm length, 10 mm outer diameter), thescrew valve600 is almost twice as long, but has the same outer diameter.
• Thescrew valve600 in accordance with one embodiment of the present invention generally includes abody660, ascrew615, ascrew actuator605, acoupling mechanism610, avalve seal620, and avalve seat670.
• Thebody660 houses the components of thescrew valve600. Thebody660 also has aninlet640 and anoutlet645. Theinlet640 may be in communication with thereservoir104 and theoutlet645 may be in communication with theinflatable portion114 of thegastric band102, or vice-versa, using suitable fluid port connectors, not shown.
• Thescrew615 includes a lead screw (where lead means a type of screw, and does not mean the material lead as used in a graphite pencil), power screw, translation screw. Thescrew615 can be designed to translate radial (e.g., circular) motion/movement into linear (e.g., translational) motion/movement. Thescrew615 is configured to apply a force on thevalve seal620 to cause thevalve seal620 to move from an open position (FIG. 6B) to a closed position (FIG. 6A) when thescrew actuator605 receives atelemetric signal124 from theremote transmitter108.
• Thescrew actuator605, positioned within thebody660 of thescrew valve600, has an actuator body defining a threadedscrew hole606. Thescrew615 is positioned within the threadedscrew hole606.
• In one embodiment, thescrew actuator605 is a motor. In another embodiment, the motor may be positioned within thescrew actuator605. In another embodiment, the motor is external to thebody660 for moving thescrew615.
• The motor (not shown) may also be included in thescrew valve600 and coupled to thescrew615 for moving thescrew615 within the threadedscrew hole606. The motor can be a DC motor, an AC motor, a solenoid, a stepper motor, a piezoelectric actuator, a piezoelectric driver, and an electroactive polymer. In one embodiment, the motor is selected to be the same type of motor used elsewhere in the implantable system. The motor can be configured to move thescrew615 to at least two positions so that thevalve seal620 can be moved to at least two positions depending on thetelemetric signal124 sent from theremote transmitter108 to theactuator605.
• Thecoupling mechanism610, positioned between thevalve seal620 and thescrew615, decouples a rotational motion of thescrew615. In one embodiment, thecoupling mechanism610 may be securely fastened or fixed to thevalve seal620 so that thecoupling mechanism610 does not rotate with the rotation of thescrew615. Thescrew615 moves forward and backward (or upward and downward) through both rotational and translational motion. However, to prevent damage to thevalve seal620, thevalve seal620 should only receive translational motion (not rotational motion). Thecoupling mechanism610 decouples the rotational motion of thescrew615 but transmits the translational motion. Thecoupling mechanism610 is illustrated as being a tappet, but can also include a ball bearing, a bellows unit, etc., as illustrated inFIGS. 7A-7C.
• Thevalve seal620 has one ormore edges621 coupled to thebody660. Thevalve seal620 is capable of being moved from an open position that is spaced apart from thevalve seat670 and does not block a fluid (e.g., saline) from flowing from theinlet640 to theoutlet645 to a closed position that blocks or contacts thevalve seat670 and does not allow the fluid to move from theinlet640 to theoutlet645. Thevalve seal620 can be in the closed position, the open position, and a partially-open position, which is between the closed position and the open position.
• Thevalve seal620, like thediaphragm520, is made of an elastomeric material. In one embodiment, the elastomeric material is silicon. However, any material that is stretchy like a rubber band can be used. For example, the elastomeric materials include flexible materials, naturally occurring elastic substances (e.g., natural rubber), and synthetically produced substances (e.g., silicon, butyl rubber, neoprene).
• Thevalve seat670 provides an opening for thevalve seal620 to close or open. To close thescrew valve600, a command signal (e.g., a telemetric signal) is sent to thescrew actuator605 which drives the screw615 (and the coupling device or mechanism610) into thevalve seal620 to press thevalve seal620 onto thevalve seat670. To open thescrew valve600, a command signal is sent to thescrew actuator605 which drives the screw615 (and the coupling device or mechanism610) away from thevalve seal620 to decompress or move thevalve seal620 away from thevalve seat670.
• The pressure/flow sensor208 may also be included in or coupled to thescrew valve600. For example, one or both of the flow sensor and/or the pressure sensor can be coupled to thevalve seat670 for determining and adjusting an amount of the fluid flowing between theinlet640 and theoutlet645.
• FIG. 6A illustrates thescrew615 displacing thevalve seal620 onto thevalve seat670 to block the fluid from flowing from theinlet640 to theoutlet645.
• FIG. 6B illustrates thescrew615 moved upward such that thevalve seal620 is not touching thevalve seat670 to allow the fluid to flow from theinlet640 to theoutlet645 as shown byfluid flow indicators675. The fluid can also flow in the opposite direction as shown by thefluid flow indicators675.
• Thelead screw valve600 provides many advantages when used for thegastric banding system100. For example, thescrew valve600 achieves a low leak/leakage rate when closed (e.g., closed/sealed tightly) compared to conventional valves and a high flow rate during adjustment. Thescrew valve600 is also easier to manufacture than other implantable devices (such as the dome valve500).
• An additional advantage, is that thescrew valve600 can remain in position (e.g., fully open, partially open, tightly closed) in the presence of very high constant and intermittent pressures present from theinlet640 and theoutlet645. For example, thescrew valve600 can handle high pressures, such as 30 psi. Thescrew valve600 can resist high pressures by being overdriven and by being a normally-still valve.
• If thescrew615 is intentionally overdriven, thescrew615 presses tightly against thecoupling mechanism610, which presses tightly against thevalve seal620, which presses tightly against thevalve seat670. The term overdriven means that thescrew615 is driven just beyond the point where thevalve seal620 contacts thevalve seat670. The phrase “just beyond” means a point where force is generated. Even though it's not possible (without damage) to move thevalve seal620 beyond the point that it touches thevalve seat670, it is possible to generate force. For example, forces develop in the motor and forces develop loading up the motor. These forces creating a force balance between thevalve seal620 and thevalve seat670. In one embodiment, “just beyond” is a point where an additional force is required from the motor.
• Even though thescrew615 drives thevalve seal620 hard into thevalve seat670, in one embodiment, thevalve seal620 is made of a soft material (e.g., silicon) and thevalve seat670 is made of a hard material (e.g., polished stainless steel) such that the two materials can be pressed together without resulting in substantial damage or marring. This tight seal blocks fluid, including fluid under high pressure. Thescrew615 can optionally be reversed to relieve any unwanted excess pressure on thescrew615, thecoupling mechanism610, thevalve seal620, and thevalve seat670.
• Another advantage of thescrew valve600 is that thescrew615 can resist the opening and closing in the presence of steady or high pressure, without requiring an additional energy, because thescrew valve600 is a normally still valve (as oppose to normally open or normally closed). Thus, in the absence of a drive command, the screw actuated valve will remain in whichever state it was left, whether that was fully open, partially open, or fully closed.
• An additional advantage of thescrew valve600 is the amount of positions available to regulate fluid flow. Thescrew valve600 can be fully open, fully closed, or anywhere in between, providing significant flexibility in designing actuation drive characteristics. The fluid flow rate can be adjusted by partially opening thescrew valve600. Thescrew seal620 can occupy any position by making precise and incremental adjustments to thescrew615. In one embodiment, thescrew valve600 is used in a closed loop system, where a sensor (e.g., flow sensor, a pressure sensor, etc.) is used to adjust the position of thescrew615 to regulate the fluid flow from theinlet640 to theoutlet645.
• FIGS. 7A,7B and7C illustrate side views of examples of thecoupling mechanism610 illustrated inFIG. 6 according to various embodiments of the present invention.FIG. 7A illustrates atappet705 as thecoupling mechanism610. Thetappet705 can be a sliding rod for moving a valve. Thetappet705 touches thescrew615, and connects or rides on thescrew615. Thetappet705 allows an intentional rotational slippage between thetappet705 and thescrew615 to decouple the rotational motion.
• FIG. 7B illustrates aball710 along with thetappet705 as thecoupling mechanism610. Theball710 is located between thescrew615 and thetappet705. Theball710 provides two surfaces designed to allow an intentional rotational slippage between thescrew615 and thevalve seal620. Having two surfaces for slippage is advantageous because one surface may bind up due to particulate contamination (e.g., particles from thescrew615 or the tappet705) or manufacturing imperfection (e.g., molding flash, burrs, etc.). Theball710 can be a ball bearing.
• FIG. 7C illustrates abellows unit715 as thecoupling mechanism610 used with thescrew615. Thebellows unit715 can isolate thescrew615 from thevalve seal620. Without thebellows unit715, thescrew615 would rotate and rub against a surface of thevalve seal620 generating particulates which are further rubbed against thevalve seal620. Since thevalve seal620 can be sensitive and not designed to be rubbed with particulates, thebellows unit715 advantageously keeps all the possible generated particulates enclosed and sealed away from thevalve seal620.
• FIG. 8 is a flow chart of a method of using thedome valve500 to control the movement of fluid between thereservoir104 and theinflatable portion114 of thegastric band102.
• The process starts atstep800. Atstep805, thedome valve500 receives a telemetric signal from theremote transmitter108. Alternatively, thedome valve500 can receive a signal from an implanted microcontroller. The implanted microcontroller may be part of, coupled to or located within theactuator505. The implanted microcontroller can receive a telemetric signal from theremote transmitter108. Next, theactuator505 applies a downward force on thediaphragm520 to open thedome valve500 atstep810. The downward force is applied onto the diaphragm edges525 of thediaphragm520 in thedome valve500, lifting up thediaphragm center527, and allowing fluid to flow through thedome valve500.
• Atstep815, theactuator505 reduces the downward force on thediaphragm520 to close thedome valve500. The downward force is reduced on the diaphragm edges525 of thediaphragm520 in thedome valve500, lowering thediaphragm center527, and blocking fluid from flowing through thedome valve500. The process ends atstep820.
• FIG. 9 is a flow chart of a method of using thescrew valve600 to control the movement of fluid between thereservoir104 and theinflatable portion114 of thegastric band102.
• The process starts atstep900. Atstep905, thescrew valve600 receives a telemetric signal from theremote transmitter108. Alternatively, thedome valve600 can receive a signal from an implanted microcontroller. The implanted microcontroller may be part of, coupled to or located within thescrew actuator605. The implanted microcontroller can receive a telemetric signal from theremote transmitter108. Atstep910, thescrew actuator605 turns thescrew615 in one direction to increase a force on thevalve seal620 to close thescrew valve600.
• Then, thescrew actuator605 turns thescrew615 in the opposite direction to decrease the force on thevalve seal620 to open thescrew valve600. The process ends atstep920.
• Unless otherwise indicated, all numbers expressing quantities of ingredients, properties such as molecular weight, reaction conditions, and so forth used in the specification and claims are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the present invention. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.
• Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements.
• The terms “a,” “an,” “the” and similar referents used in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. Recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the present invention.
• Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member may be referred to and claimed individually or in any combination with other members of the group or other elements found herein. It is anticipated that one or more members of a group may be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is deemed to contain the group as modified thus fulfilling the written description of all Markush groups used in the appended claims.
• Certain embodiments of the present invention are described herein, including the best mode known to the inventors for carrying out the present invention. Of course, variations on these described embodiments will become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventor expects skilled artisans to employ such variations as appropriate, and the inventors intend for the present invention to be practiced otherwise than specifically described herein. Accordingly, the present invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the present invention unless otherwise indicated herein or otherwise clearly contradicted by context.
• Furthermore, references may have been made to patents and printed publications in this specification. Each of the above-cited references and printed publications are individually incorporated herein by reference in their entirety.
• Specific embodiments disclosed herein may be further limited in the claims using consisting of or and consisting essentially of language. When used in the claims, whether as filed or added per amendment, the transition term “consisting of” excludes any element, step, or ingredient not specified in the claims. The transition term “consisting essentially of” limits the scope of a claim to the specified materials or steps and those that do not materially affect the basic and novel characteristic(s). Embodiments of the present invention so claimed are inherently or expressly described and enabled herein.
• In closing, it is to be understood that the embodiments of the present invention disclosed herein are illustrative of the principles of the present invention. Other modifications that may be employed are within the scope of the present invention. Thus, by way of example, but not of limitation, alternative configurations of the present invention may be utilized in accordance with the teachings herein. Accordingly, the present invention is not limited to that precisely as shown and described.

Claims (20)

1. An implantable device for controlling movement of a fluid to an inflatable portion of a gastric band, the implantable device comprising:

a body having an inlet, an outlet and a valve seat positioned between the inlet and the outlet, the body defining a fluid passage from the inlet to the outlet;

a diaphragm having one or more edges coupled to the body, the diaphragm being made of an elastomeric material and capable of being moved from a closed position that blocks the valve seat and does not allow the fluid to move from the inlet to the outlet to an open position that does not block the valve seat and allows the fluid to move from the inlet to the outlet;

an actuator configured to apply a force on the diaphragm causing the diaphragm to move from the closed position to the open position; and

a microcontroller coupled to the actuator, the microcontroller configured to receive a telemetric signal from a remote transmitter and control the actuator based on the telemetric signal.

2. The implantable device ofclaim 1 further comprising a cap, coupled between the diaphragm and the actuator, for directing the force from the actuator to the diaphragm.

3. The implantable device ofclaim 1 wherein the force is applied on the one or more edges of the diaphragm.

4. The implantable device ofclaim 1 wherein the diaphragm moves in a direction substantially opposite to a direction of the force.

5. The implantable device ofclaim 1 wherein the diaphragm prevents the fluid from coming into direct contact with the actuator.

6. The implantable device ofclaim 1 wherein the diaphragm is made of a flexible material.

7. The implantable device ofclaim 1 wherein the diaphragm is in the open position when the actuator is in an energized state.

8. The implantable device ofclaim 1 wherein the diaphragm is in the closed position when the actuator is in an unenergized state.

9. The implantable device ofclaim 1 wherein the actuator is selected from a group consisting of a solenoid, a stepper motor, a piezoelectric actuator, an electroactive polymer, and combinations thereof.

10. The implantable device ofclaim 1 wherein the remote transmitter transmits the telemetric signal to the microcontroller.

11. An implantable device that controls the movement of fluid to an inflatable portion of a gastric band, the implantable device comprising:

a body having an inlet, an outlet and a valve seat, the body defining a fluid passage from the inlet to the outlet;

a valve seal having one or more edges coupled to the body, the valve seal being made of an elastomeric material and capable of being moved from an open position that does not block the valve seat and allows the fluid to move from the inlet to the outlet to a closed position that blocks the valve seat and does not allow the fluid to move from the inlet to the outlet; and

an actuator having an actuator body defining a threaded screw hole and positioned within the body and a screw positioned within the threaded screw hole, the screw configured to apply a force on the valve seal causing the valve seal to move from the open position to the closed position when the actuator receives a telemetric signal from a remote transmitter.

12. The implantable device ofclaim 11 further comprising a motor, positioned within the actuator body, for moving the screw within the threaded screw hole.

13. The implantable device ofclaim 12 wherein the motor is selected from a group consisting of a DC motor, an AC motor, a solenoid, a stepper motor, a piezoelectric actuator, a piezoelectric driver, an electroactive polymer, and combinations thereof.

14. The implantable device ofclaim 13 wherein the motor is configured to move the screw to a first screw position so that the valve seal can be moved to a first valve seal position depending on the telemetric signal received from the remote transmitter.

15. The implantable device ofclaim 14 wherein the first valve seal position is selected from a group consisting of the closed position, the open position, and a partially-open position which is between the closed position and the open position.

16. The implantable device ofclaim 11 further comprising a coupling mechanism, positioned between the valve seal and the screw, for decoupling a rotational motion of the screw but allowing for a translational motion of the screw.

17. The implantable device ofclaim 16 wherein the coupling mechanism is selected from a group consisting of a tappet, a ball bearing, a bellows unit, and combinations thereof.

18. The implantable device ofclaim 11 further comprising a flow sensor, coupled to the valve seat, for determining and adjusting an amount of the fluid flowing between the inlet and the outlet.

19. The implantable device ofclaim 11 further comprising a pressure sensor, coupled to the valve seat, for determining and adjusting a pressure of the fluid flowing between the inlet and the outlet.

20. The implantable device ofclaim 11 wherein the remote transmitter transmits the telemetric signal to the actuator.

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