FIELD OF THE INVENTIONThe present invention generally relates to a gastroesophageal flap valve restoration device for treating gastroesophageal reflux disease. The present invention more particularly relates to an invaginator for use in such devices that grips the esophagus during treatment and restricts axial device movement while permitting relatively free rotational device movement.
BACKGROUNDGastroesophageal reflux disease (GERD) is a chronic condition caused by the failure of the anti-reflux barrier located at the gastroesophageal junction to keep the contents of the stomach from splashing into the esophagus. The splashing is known as gastroesophageal reflux. The stomach acid is designed to digest meat, and will digest esophageal tissue when persistently splashed into the esophagus.
A principal reason for regurgitation associated with GERD is the mechanical failure of a deteriorated gastroesophageal flap to close and seal against high pressure in the stomach. Due to reasons including lifestyle, a Grade I normal gastroesophageal flap may deteriorate into a malfunctioning Grade III or absent valve Grade IV gastroesophageal flap. With a deteriorated gastroesophageal flap, the stomach contents are more likely to be regurgitated into the esophagus, the mouth, and even the lungs. The regurgitation is referred to as “heartburn” because the most common symptom is a burning discomfort in the chest under the breastbone. Burning discomfort in the chest and regurgitation (burping up) of sour-tasting gastric juice into the mouth are classic symptoms of gastroesophageal reflux disease (GERD). When stomach acid is regurgitated into the esophagus, it is usually cleared quickly by esophageal contractions. Heartburn (backwashing of stomach acid and bile onto the esophagus) results when stomach acid is frequently regurgitated into the esophagus and the esophageal wall is inflamed.
Complications develop for some people who have GERD. Esophagitis (inflammation of the esophagus) with erosions and ulcerations (breaks in the lining of the esophagus) can occur from repeated and prolonged acid exposure. If these breaks are deep, bleeding or scarring of the esophagus with formation of a stricture (narrowing of the esophagus) can occur. If the esophagus narrows significantly, then food sticks in the esophagus and the symptom is known as dysphagia. GERD has been shown to be one of the most important risk factors for the development of esophageal adenocarcinoma. In a subset of people who have severe GERD, if acid exposure continues, the injured squamous lining is replaced by a precancerous lining (called Barrett's Esophagus) in which a cancerous esophageal adenocarcinoma can develop.
Other complications of GERD may not appear to be related to esophageal disease at all. Some people with GERD may develop recurrent pneumonia (lung infection), asthma (wheezing), or a chronic cough from acid backing up into the esophagus and all the way up through the upper esophageal sphincter into the lungs. In many instances, this occurs at night, while the person is in a supine position and sleeping. Occasionally, a person with severe GERD will be awakened from sleep with a choking sensation. Hoarseness can also occur due to acid reaching the vocal cords, causing a chronic inflammation or injury. GERD never improves without intervention. Life style changes combined with both medical and surgical treatments exist for GERD. Medical therapies include antacids and proton pump inhibitors. However, the medical therapies only mask the reflux. Patients still get reflux and perhaps emphysema because of particles refluxed into the lungs. Barrett's esophagus results in about 10% of the GERD cases. The esophageal epithelium changes into tissue that tends to become cancerous from repeated acid washing despite the medication.
Several open laparotomy and laparoscopic surgical procedures are available for treating GERD. One surgical approach is the Nissen fundoplication. The Nissen approach typically involves a 360-degree wrap of the fundus around the gastroesophageal junction. The procedure has a high incidence of postoperative complications. The Nissen approach creates a 360-degree moveable flap without a fixed portion. Hence, Nissen does not restore the normal movable flap. The patient cannot burp because the fundus was used to make the repair, and may frequently experience dysphagia. Another surgical approach to treating GERD is the Belsey Mark IV (Belsey) fundoplication. The Belsey procedure involves creating a valve by suturing a portion of the stomach to an anterior surface of the esophagus. It reduces some of the postoperative complications encountered with the Nissen fundoplication, but still does not restore the normal movable flap. None of these procedures fully restores the normal anatomical anatomy or produces a normally functioning gastroesophageal junction. Another surgical approach is the Hill repair. In the Hill repair, the gastroesophageal junction is anchored to the posterior abdominal areas, and a 180-degree valve is created by a system of sutures. The Hill procedure restores the moveable flap, the cardiac notch and the Angle of His. However, all of these surgical procedures are very invasive, regardless of whether done as a laparoscopic or an open procedure.
New, less surgically invasive approaches to treating GERD involve transoral endoscopic procedures. One procedure contemplates a machine device with robotic arms that is inserted transorally into the stomach. While observing through an endoscope, an endoscopist guides the machine within the stomach to engage a portion of the fundus with a corkscrew-like device on one arm. The arm then pulls on the engaged portion to create a fold of tissue or radial plication at the gastroesophageal junction. Another arm of the machine pinches the excess tissue together and fastens the excess tissue with one pre-tied implant. This procedure does not restore normal anatomy. The fold created does not have anything in common with a valve. In fact, the direction of the radial fold prevents the fold or plication from acting as a flap of a valve.
Another transoral procedure contemplates making a fold of fundus tissue near the deteriorated gastroesophageal flap to recreate the lower esophageal sphincter (LES). The procedure requires placing multiple U-shaped tissue clips around the folded fundus to hold it in shape and in place.
This and the previously discussed procedure are both highly dependent on the skill, experience, aggressiveness, and courage of the endoscopist. In addition, these and other procedures may involve esophageal tissue in the repair. Esophageal tissue is fragile and weak, in part due to the fact, that the esophagus is not covered by serosa, a layer of very sturdy, yet very thin tissue, covering and stabilizing all intraabdominal organs, similar like a fascia covering and stabilizing muscle. Involvement of esophageal tissue in the repair of a gastroesophageal flap valve poses unnecessary risks to the patient, such as an increased risk of fistulas between the esophagus and the stomach.
A new and improved apparatus and method for restoration of a gastroesophageal flap valve is fully disclosed in U.S. Pat. No. 6,790,214, issued Sep. 14, 2004, is assigned to the assignee of this invention, and is incorporated herein by reference. That apparatus and method provides a transoral endoscopic gastroesophageal flap valve restoration. A longitudinal member arranged for transoral placement into a stomach carries a tissue shaper that non-invasively grips and shapes stomach tissue. A tissue fixation device is then deployed to maintain the shaped stomach tissue in a shape approximating a gastroesophageal flap.
Whenever tissue is to be maintained in a shape as, for example, in the improved assembly last mentioned above, it is necessary to first grip stomach tissue and then fasten at least two layers of gripped tissue together. In applications such as gastroesophageal flap valve restoration, it is desirable to grip stomach tissue displaced from the esophageal opening into the stomach so that when the stomach tissue is pulled aborally to form a flap, the flap will have sufficient length to cover the opening and function as a flap valve. With the gastroesophageal anatomy thus restored, the GERD will be effectively treated.
Locating the proper gripping point in the stomach is not a simple matter. Once a desired gripping point is found, it is then necessary to form the GEFV flap and maintain its shape without involving the esophageal tissue. Still further, these manipulations of the stomach tissue must be incrementally repeated many times as the device is rotated to form a complete valve. Such further manipulation must repeat the dimensions of the manipulated stomach tissue to result in a valve structure of uniform geometry. This requires the device to be disposed in a repeatable axial position for each manipulation. Unfortunately, this is extremely difficult under the circumstances provided by the anatomy of the stomach.
Hence, there is a need in the art for techniques and devices, which enable repeatable uniform manipulations of stomach tissue from within the stomach to restore a GEFV. The present invention addresses these and other issues.
SUMMARYThe invention provides an assembly comprising a medical instrument including an elongated member configured to be fed into a body space having sidewalls and an invaginator carried by the elongated member, the invaginator being configured to grip the body space sidewalls. The elongated member and invaginator are coupled for restricted relative axial movement and substantially free relative rotational movement.
The invention further provides an assembly comprising an elongated member configured to be fed through a throat, down an adjoining esophagus and into an associated stomach. The elongated member has a distal end. The assembly further includes a gastroesophageal flap valve restoration device carried on the distal end of the elongated member for placement in the stomach and an invaginator carried by the elongated member. The invaginator is configured to grip the esophagus and the elongated member and invaginator are coupled for restricted relative axial movement and substantially free relative rotational movement.
The invaginator may be configured to non-invasively grip the esophagus. To this end, the invaginator may be configured to vacuum-grip the esophagus.
The assembly may further comprise a conduit that couples the invaginator to a vacuum source. The conduit may comprise a lumen formed in the elongated member. Alternatively, the conduit may comprise an elongated tubular member independent of the elongated member.
The invaginator preferably circumscribes the elongated member. The assembly may further comprise a bearing assembly between the invaginator and the elongated member.
The bearing assembly may comprise at least one bearing sleeve. The bearing assembly may comprise an inner bearing sleeve and an outer bearing sleeve. The inner bearing sleeve and outer bearing sleeve are preferably coaxially disposed between the invaginator and the elongated member. A lubricant may be applied to the bearing assembly.
The elongated member may include a discrete axial length portion of reduced cross-sectional dimension and the invaginator may be confined within the discrete axial length portion to restrict its axial movement. Alternatively, the invaginator may extend substantially coextensively along the elongated member.
The invention further provides an assembly comprising an elongated member configured to be fed through a throat, down an adjoining esophagus and into an associated stomach, the elongated member having a distal end, a gastroesophageal flap valve restoration device carried on the distal end of the elongated member for placement in the stomach, and an invaginator carried by and circumscribing the elongated member. The invaginator is configured to vacuum grip the esophagus and the elongated member and invaginator are coupled for restricted relative axial movement and substantially free relative rotational movement.
The invention further provides an assembly comprising an elongated member having a distal end and configured to be fed through a throat, down an adjoining esophagus and into an associated stomach, a gastroesophageal flap valve restoration device carried on the distal end of the elongated member for placement in the stomach, an invaginator carried by and circumscribing the elongated member, the invaginator being configured to vacuum grip the esophagus, and a bearing assembly between the invaginator and the elongated member. The bearing assembly couples the elongated member and invaginator for restricted relative axial movement and substantially free relative rotational movement.
BRIEF DESCRIPTION OF THE DRAWINGSThe features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The invention, together with further objects and advantages thereof, may best be understood by making reference to the following description taken in conjunction with the accompanying drawings, in the several figures of which like reference numerals identify like elements, and wherein:
FIG. 1 is a front cross-sectional view of the esophageal-gastro-intestinal tract from a lower portion of the esophagus to the duodenum;
FIG. 2 is a front cross-sectional view of the esophageal-gastro-intestinal tract illustrating a Grade I normal appearance movable flap of the gastroesophageal flap valve (in dashed lines) and a Grade III reflux appearance gastroesophageal flap of the gastroesophageal flap valve (in solid lines);
FIG. 3 is a side view of an apparatus for restoring a GEFV having an invaginator according to an embodiment of the invention;
FIG. 4 is a partial side view of the apparatus ofFIG. 3 showing the invaginator according to an embodiment of the invention in greater detail;
FIG. 5 is a side view of another apparatus for restoring a GEFV including an invaginator according to another embodiment of the invention;
FIG. 6 is a partial side view of the apparatus ofFIG. 5 showing the invaginator in greater detail; and
FIG. 7 is a side view of an apparatus according to a still further embodiment.
DETAILED DESCRIPTIONFIG. 1 is a front cross-sectional view of the esophageal-gastro-intestinal tract40 from a lower portion of theesophagus41 to theduodenum42. Thestomach43 is characterized by thegreater curvature44 on the anatomical left side and thelesser curvature45 on the anatomical right side. The tissue of the outer surfaces of those curvatures is referred to in the art as serosa tissue. As will be seen subsequently, the nature of the serosa tissue is used to advantage for its ability to bond to like serosa tissue.
Thefundus46 of thegreater curvature44 forms the superior portion of thestomach43, and traps gas and air bubbles for burping. Theesophageal tract41 enters thestomach43 at an esophageal orifice below the superior portion of thefundus46, forming acardiac notch47 and an acute angle with respect to thefundus46 known as the Angle of His57. The lower esophageal sphincter (LES)48 is a discriminating sphincter able to distinguish between burping gas, liquids, and solids, and works in conjunction with thefundus46 to burp. The gastroesophageal flap valve (GEFV)49 includes a moveable portion and an opposing more stationary portion.
The moveable portion of theGEFV49 is an approximately 180 degree, semicircular, gastroesophageal flap50 (alternatively referred to as a “normal moveable flap” or “moveable flap”) formed of tissue at the intersection between theesophagus41 and thestomach43. The opposing more stationary portion of theGEFV49 comprises a portion of thelesser curvature45 of thestomach43 adjacent to its junction with theesophagus41. Thegastroesophageal flap50 of theGEFV49 principally comprises tissue adjacent to thefundus46 portion of thestomach43. It is about 4 to 5 cm long (51) at it longest portion, and its length may taper at its anterior and posterior ends.
Thegastroesophageal flap50 is partially held against thelesser curvature45 portion of thestomach43 by the pressure differential between thestomach43 and the thorax, and partially by the resiliency and the anatomical structure of theGEFV49, thus providing the valving function. TheGEFV49 is similar to a flutter valve, with thegastroesophageal flap50 being flexible and closeable against the other more stationary side.
The esophageal tract is controlled by an upper esophageal sphincter (UES)in the neck near the mouth for swallowing, and by theLES48 and theGEFV49 at the stomach. The normal anti-reflux barrier is primarily formed by theLES48 and theGEFV49 acting in concert to allow food and liquid to enter the stomach, and to considerably resist reflux of stomach contents into theesophagus41 past thegastroesophageal tissue junction52. Tissue aboral of thegastroesophageal tissue junction52 is generally considered part of the stomach because the tissue protected from stomach acid by its own protective mechanisms. Tissue oral of thegastroesophageal junction52 is generally considered part of the esophagus and it is not protected from injury by prolonged exposure to stomach acid. At thegastroesophageal junction52, the juncture of the stomach and esophageal tissues form a zigzag line, which is sometimes referred to as the “Z-line.” For the purposes of these specifications, including the claims, “stomach” means the tissue aboral of thegastroesophageal junction52.
FIG. 2 is a front cross-sectional view of an esophageal-gastro-intestinal tract illustrating a Grade I normal appearancemovable flap50 of the GEFV49 (shown in dashed lines) and a deteriorated Grade IIIgastroesophageal flap55 of the GEFV49 (shown in solid lines). As previously mentioned, a principal reason for regurgitation associated with GERD is the mechanical failure of the deteriorated (or reflux appearance)gastroesophageal flap55 of theGEFV49 to close and seal against the higher pressure in the stomach. Due to reasons including lifestyle, a Grade I normalgastroesophageal flap50 of theGEFV49 may deteriorate into a Grade III deterioratedgastroesophageal flap55. The anatomical results of the deterioration include moving a portion of theesophagus41 that includes thegastroesophageal junction52 andLES48 toward the mouth, straightening of thecardiac notch47, and increasing the Angle of His57. This effectively reshapes the anatomy aboral of thegastroesophageal junction52 and forms a flattenedfundus56.
The deterioratedgastroesophageal flap55 shown inFIG. 2 has agastroesophageal flap valve49 andcardiac notch47 that are both significantly degraded. Dr. Hill and colleagues developed a grading system to describe the appearance of the GEFV and the likelihood that a patient will experience chronic acid reflux. L. D. Hill, et al.,The gastroesophageal flap valve: in vitro and in vivo observations,Gastrointestinal Endoscopy 1996:44:541-547. Under Dr. Hill's grading system, the normalmovable flap50 of theGEFV49 illustrates a Grade I flap valve that is the least likely to experience reflux. The deterioratedgastroesophageal flap55 of theGEFV49 illustrates a Grade III (almost Grade IV) flap valve. A Grade IV flap valve is the most likely to experience reflux. Grades II and III reflect intermediate grades of deterioration and, as in the case of III, a high likelihood of experiencing reflux. With the deteriorated GEFV represented by deterioratedgastroesophageal flap55 and thefundus46 moved inferior, the stomach contents are presented a funnel-like opening directing the contents into theesophagus41 and the greatest likelihood of experiencing reflux. Disclosed subsequently are a device, assembly, and method, which may be employed to advantage according to an embodiment of the invention in restoring the normal gastroesophageal flap valve anatomy.
Referring now toFIG. 3, it shows anapparatus100 according to an embodiment of the present invention positioned for the restoration of a GEFV. Theapparatus100 includes anelongated member102 having adistal end104 for transoral placement into thestomach43. Carried on the distal end of theelongated member102 is adevice110 for restoring the GEFV. Thedevice110 includes afirst member114, hereinafter referred to as the chassis, and asecond member116, hereinafter referred to as the bail. Thechassis114 andbail116 are hingedly coupled at117. Thechassis114 andbail116 form a tissue shaper which, as described in copending U.S. application Ser. No. 11/172,427 and incorporated herein in its entirety by reference, shapes tissue of thestomach43 into the flap of a restored gastroesophageal flap valve (GEFV).
Thedevice110 has a longitudinal passage to permit anendoscope120 to be guided through the device and into the stomach. This permits the endoscope to serve as a guide for guiding thedevice110 through the patient's throat, down theesophagus41, and into the stomach. It also permits the gastroesophageal flap valve restoration procedure to be viewed at each stage of the procedure.
To facilitate shaping of the stomach tissue, the stomach tissue is drawn in between thechassis114 and thebail116. Further, to enable a flap of sufficient length to be formed to function as the flap of a gastroesophageal flap valve, the stomach tissue is pulled down so that the fold line is substantially juxtaposed to the opening of the esophagus into the stomach. Hence, the stomach is first gripped at a point out and away from the esophagus and the grip point is pulled to almost the hingedconnection117 of thechassis114 andbail116. As described in copending application Ser. No. 11/001,666, filed Nov. 30, 2004, entitled FLEXIBLE TRANSORAL ENDOSCOPIC GASTROESOPHAGEAL FLAP VALVE RESTORATION DEVICE AND METHOD, which application is incorporated herein by reference, thedevice110 is fed down the esophagus with thebail116 substantially in line with thechassis114. To negotiate the bend of the throat, and as described in the aforementioned referenced application, thechassis114 andbail116 are rendered flexible. Thechassis114 is rendered flexible byslots118 and thebail116 is rendered flexible by the hingedly coupledlinks122. Further details concerning the flexibility of thechassis114 and thebail116 may be found in the aforementioned referenced application.
As further shown inFIG. 3, the device further includes atissue gripper124. Thegripper124, in this embodiment, comprises ahelical coil125. Thecoil125 is carried at the end of a cable126 and may be attached to the end of the cable or be formed from the cable. In this embodiment, thehelical coil125 is attached to the cable126 and is preceded by aguide128 whose function will be described subsequently.
Thehelical coil125 is shown in an approximate position to engage the stomach tissue out and away from the opening of the esophagus to the stomach. Thehelical coil125 is guided into position by aguide structure130 carried on thebail116. Theguide structure130 comprises aguide tube132. When thedevice110 is first introduced down the esophagus into the stomach, thehelical coil125 is caused to reside well within theguide tube132 to preclude the helical coil from accidentally or inadvertently snagging esophageal or stomach tissue.
The guide tube includes alongitudinal slit136 having a circuitous configuration. Theslit136 permits the end of the cable to release or disassociate from the bail after the stomach tissue is gripped. The circuitous configuration of theslit136 assures confinement of the cable126 within theguide tube132 until release of the cable is desired. The proximal end of theslit136 has an enlarged portion or opening (not shown). This opening permits the cable and helical coil to reenter the lumen when thedevice110 is readied for a repeated stomach tissue shaping procedure. To that end, theguide128 has a conical surface that serves to guide the cable end back into the opening of theslit136.
With continued reference toFIG. 3, thedevice110 further comprises afastener deployer150. The fastener deployer includes at least onefastener deployment guide152. Thefastener deployment guide152 takes the form of a guide lumen. Although only oneguide lumen152 is shown, it will be appreciated that thedevice110 may include a plurality of such lumens without departing from the invention. The guide lumen terminates at adelivery point154 where a fastener is driven into the molded stomach tissue. The fastener deployer may take the form of any one of the assemblies fully described and claimed, for example, in copending U.S. application Ser. No. 11/043,903 which application is owned by the assignee of this invention and incorporated herein by reference.
Thedevice110 further includes awindow140 within thechassis114. The window is formed of a transparent or semi-transparent material. This permits gastroesophageal anatomy, and more importantly the gastroesophageal junction52 (Z-line) to be viewed with theendoscope120. The window includes alocation marker142 which has a known position relative to thefastener delivery point154. Hence, by aligning the marker with a known anatomical structure, the fastener will be delivered a known distance from or at a location having a predetermined relation to the marker. For example, by aligning the marker with or below the Z-line, it will be known that the fastener will be placed aboral of the Z-line and that serosa tissue will be fastened to serosa tissue. As previously mentioned, this has many attendant benefits.
According to this embodiment, theapparatus100 further includesinvaginator155. Theinvaginator155 is a double walledtoroidal structure170 having a hollow center. A plurality oforifices156 communicate with the hollow center. Theseorifices156, are used to pull a vacuum to cause theinvaginator155 to grip the tissue wall of the esophagus. This will serve to stabilize the esophagus and maintaindevice110 positioning during the procedure. This vacuum gripping of the esophagus may also be used to particular advantage if the patient suffers from a hiatal hernia.
More specifically, theinvaginator155 is so arranged with respect to theelongated member102 that, once the invaginator grips theesophagus41, the device is permitted very little axial movement with respect to the invaginator but is permitted relatively free rotational movement with respect to the invaginator. This permits thedevice110 to be rotated in increments for stomach tissue folding while maintaining a substantially constant axial position within the stomach. Hence, theinvaginator155 avoids the prior need of releasing the invaginator to permit device rotation and then realigning the device at the proper axial position for the next incremental folding procedure.
As may be best noted inFIG. 4, theinvaginator155 is seated against a bearingsurface portion160 of theelongated member102. The bearingsurface portion160 is formed from atubular member162 which is secured in place by retention rings164 and166. The toroidal orring structure170 circumscribes the bearing surface portion and is axially confined between retention rings164 and166. The interior of thering structure170 may be coupled to a vacuum source (not shown) through aflexible conduit180 and alumen182 in theelongated member102. This permits the invaginator to non-invasively grip the esophagus through a vacuum-grip applied throughorifices156. Theconduit180 may be covered by a thin membrane or sheath (not shown) to help prevent theconduit180 from snagging during deployment.
The bearingsurface portion160 forms part of a bearingassembly190 coupling theinvaginator155 to theelongated member102. The bearing assembly further includes aninner bearing surface191 of thering structure170. This bearing assembly190 permits relatively free relative rotational movement of theelongated member102 and thusdevice110 with respect to theinvaginator155 and the anatomy.
The bearingassembly190 may further include anoptional bearing sleeve192 between theinner bearing surface191 and bearingsurface portion160 and axially between the retention rings164 and166. Thesleeve192 serves to further reduce friction against the spaces between thesleeve192 andsurface portion160 andsurface191 may be packed with asuitable lubricant194 to still further reduce rotational friction.
In use, as described in the aforementioned copending U.S. application Ser. No. 11/172,427, thedevice110 is introduced through the patient's mouth, throat, esophagus and into the stomach with thebail116 substantially in line with thechassis114. After the z line is observed through thewindow140 and themarker142 set at or aboral of the z line, thestomach43 is partially inflated to permit visualization with theendoscope120. This allows a first gripping site within the stomach for the first fold to restore the GEFV. When the site is found, a vacuum is pulled through theinvaginator155 to grip the esophagus. Thehelix125 is then screwed into the stomach wall. The stomach is then pulled between thechassis114 and thebail116 to form a first fold and one or more fasteners are delivered by thefastener deployer150 to maintain the first fold. Then, thehelix125 is released from the stomach tissue.
At this point in the prior art, it has been necessary to release the invaginator vacuum grip to permit theassembly100 to be rotated for the next incremental fold. The position of thedevice110 would then be checked by moving theendoscope120 back for visualizing the device and the z line would be located through thewindow140. The axial position of the device would then be adjusted if necessary. The vacuum grip would then be reestablished by the invaginator for the next incremental fold.
In contrast, by virtue of the invaginator of this embodiment, the vacuum grip need not be interrupted to permit rotation of thedevice110 in the proper position for the next incremental fold. Once thehelix125 releases the tissue, the device may be rotated with the bearingassembly190. The next fold may then be made. No other repositioning of the device or manipulation of the endoscope is necessary.
To further assist maintaining theinvaginator155 in its axial position onelongated member102, or as a sole means along withconduit180, theinvaginator155 may be tethered to thechassis114 by a flexible non-stretchable tether (not shown). This may serve to eliminate the need for retention rings164 and166.
FIG. 5 shows anotherassembly200 according to another embodiment of the present invention. Theassembly200 is essentially identical to theassembly100 ofFIG. 3 except for the design of the bearingsurface portion260, theinvaginator255, and the bearingassembly290. Hence for clarity, like reference numerals for like elements have been carried over fromFIG. 3 toFIG. 5.
FIG. 6 shows the bearingsurface portion260 and bearingassembly290 in greater detail. As may be noted, the bearingsurface portion260 is an extension of theelongated member102 and is partly defined by aring262 which creates anannular retention shoulder264. The other end of the bearingsurface portion260 is sealed to anotherring266 carried by thedevice110 to form anotherretention shoulder268. Again, theinvaginator255 includes a hollow doublewalled ring270 that circumscribes the bearingsurface portion260. Theinvaginator ring255 includesorifices256 through which a vacuum may be drawn for vacuum gripping the esophagus. The vacuum is pulled through aconduit280 that extends along side and external to theelongated member102.
The bearingassembly290, according to this embodiment, includes a pair of bearing sleeves, anouter bearing sleeve292 and aninner bearing sleeve296. The bearingsleeves292 and296 are coaxially arranged about the bearingsurface portion260. Again, asuitable lubricant296 may be provided between theinner bearing surface291 ofring270 andsleeve292, betweensleeve292 andsleeve296, and betweensleeve296 and thebearing surface portion260.
Each of the invaginators described herein may be rendered flexible by being formed of flexible material. This enables the invaginators to conform to non-circular structures while still permitting rotation.
Theassembly200 may be used as previously described with respect toassembly100. Theconduit280 is preferably flexible to permit relatively free rotational movement of theelongated member102 anddevice110 with respect to theinvaginator ring270 and hence the anatomy.
FIG. 7 shows another assembly300 according to still another embodiment of the present invention. The assembly300 is again essentially identical to theassembly100 ofFIG. 3 in terms of thedevice110 but differs in the design of the invaginator355. Again, for clarity, like reference numerals for like elements have been carried over fromFIG. 3 toFIG. 7.
As may be noted inFIG. 7, the invaginator355 is full length in that it may extend orally along the length of and substantially coextensive with theelongated member102. The invaginator355 still includes orifices356 through which a vacuum may be drawn for vacuum gripping the esophagus. The vacuum may be pulled through a conduit (not shown) or the annular space380 between theelongated member102 and the invaginator355.
According to this embodiment, the invaginator includes a sealed bearing390 permitting theelongated member102 anddevice110 to freely rotate with respect to the invaginator355. A suitable lubricant may be provided between the bearing390 and thedevice110 at the adjoining surfaces394.
The assembly300 may be used as previously described with respect toassembly100. The conduit invaginator355 is preferably flexible to permit the assembly to be fed through the throat, and esophagus into thestomach43.
While particular embodiments of the present invention have been shown and described, modifications may be made, and it is thereto intended in the appended claims to cover all such changes and modifications which fall within the true spirit and scope of the invention.