Inflatable and adjustable gastric band for treating obesity

Abstract

An inflatable, adjustable gastric band includes a flexible, hollow, resilient band; and a flexible inflation tube connected to the band and complementary closing means that are capable of mutually engaging so as to lock a ring in a closed position. The ring formed by bringing the distal end and the proximal end of the band together into a slipknot. The hollow band has, in an inoperative position, a preformed curved portion which is extended, by a substantially rectilinear portion, from the proximal end area thereof to the free distal end of the band. The substantially rectilinear portion being suitable for facilitating the insertion of the proximal end of the tube through the loop(s) of the band, and in that the hollow band has, on the outer wall thereof, two loops, said loops being arranged on the substantially rectilinear portion of the hollow band.

Claims

1. An inflatable and adjustable gastric band to be positioned around a segment of the digestive tract in order to narrow said segment, said gastric band comprising: a hollow flexible band, which is resilient and comprises an inner wall and an outer wall defining an inflatable leaktight chamber with an inflation opening; a flexible inflation tube whose distal end is connected to the inflation opening of the band, and whose proximal end is intended to be connected to inflation means; the tube and the band being provided, in respective distal end areas thereof, with complementary closure means and that are able to mutually engage so as to lock a ring in a closed position, said ring being formed by bringing a distal end and a proximal end of the band together; the closure means of the tube being at least one notch and the closure means of the band being at least one loop, such that the proximal end of the tube is configured to be engaged through the at least one loop of the band as far as a locked closure position once said at least one notch is brought beyond said at least one loop; wherein the hollow flexible band, when not in use and when the tube and the band are not engaged in each other to form the ring, has a preformed curved part which extends starting from a proximal end area thereof and which is continued via a substantially rectilinear part to the distal end of the band, said substantially rectilinear part has a length between 10 and 40% of the total length of the hollow flexible band for facilitating the engagement of the proximal end of the tube through said at least one loop of the band, and said at least one loop being arranged on an outer wall of the substantially rectilinear part of the hollow flexible band.

2. The gastric band as claimed in claim 1, wherein an axis of the substantially rectilinear part of the band intersects the distal end area of the tube.

3. The gastric band as claimed in claim 1, wherein the distal end area of the tube has a substantially rectilinear part when not in use and when the tube and the band are not engaged in each other to form the ring.

4. The gastric band as claimed in claim 3, wherein an angle A formed by the substantially rectilinear part of the band (2) and the substantially rectilinear part of the tube is less than or equal to 50.

5. The gastric band as claimed in claim 3, wherein an angle A formed by the substantially rectilinear part of the band and the substantially rectilinear part of the tube is between 20 and 50.

6. The gastric band as claimed in claim 3, wherein an angle A formed by the substantially rectilinear part of the band and the substantially rectilinear part of the tube is between 40 and 90.

7. The gastric band as claimed in claim 3, wherein an angle A formed by the substantially rectilinear part of the band and the substantially rectilinear part of the tube is less than or equal to 60.

8. The gastric band as claimed in claim 1, wherein the proximal end area of the band is substantially rectilinear.

9. The gastric band as claimed in claim 1, wherein the hollow band is in one piece, and wherein the hollow band is produced from at least two materials M1, M2, which differ from each other at least in terms of their respective hardness D1, D2, with D1 >D2, the material M1 constituting at least part of the outer wall, and the material M2 constituting at least part of the inner wall.

10. The gastric band as claimed in claim 9, wherein the at least two materials M1, M2 are chosen from silicone elastomers.

11. The gastric band as claimed in claim 1, wherein the outer wall of the hollow flexible band comprises longitudinal edges and at least the longitudinal edges of the outer wall are protuberant.

12. The gastric band as claimed in claim 11, wherein the longitudinal edges (22) of the outer wall (18) are at least partially radiopaque.

13. The gastric band as claimed in claim 1, wherein the inflation opening is formed in an outer wall of the proximal end area of the band, and wherein said outer wall has, on its inner face, recesses of which at least some of said recesses are arranged on each side of the inflation opening, said recesses being intended to prevent occlusion of the inflation opening by the inner wall of the hollow band opposite said inflation opening during deflation.

14. The gastric band as claimed in claim 1, comprising a radiopaque insert lodged in the hollow band.

15. The gastric band (1) as claimed in claim 1, wherein the closure means (11) of the band (2) comprises at least two loops arranged on the outer wall (18) of the substantially rectilinear part (15) of the hollow flexible band (2).

16. The gastric band (1) as claimed in claim 1, wherein the length of the substantially rectilinear part (15) of the hollow flexible band (2) is between 17 and 35% of the total length of the hollow flexible band.

17. The gastric band (1) as claimed in claim 1, wherein the length of the substantially rectilinear part (15) of the hollow flexible band (2) is between 21 and 33% of the total length of the hollow flexible band.

18. The gastric band as claimed in claim 3, wherein an angle A formed by the substantially rectilinear part of the band and the substantially rectilinear part of the tube is equal to 45.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Other distinguishing features of the gastric band according to the invention will become clear from the following description of a preferred embodiment. This detailed description is made with reference to the attached figures, in which:

(2) FIG. 1 shows a prior art gastric belt,

(3) FIG. 2 is a side view of the gastric band according to the invention when not in use, in the deflated state and in the open position (without the hollow flexible band and the tube being engaged in each other to form a loop),

(4) FIG. 3 is a sectional view of FIG. 2 in the median longitudinal plane (line III-III in FIG. 4),

(5) FIG. 4 is a bottom view of FIG. 2,

(6) FIG. 5 is a top view of FIG. 2,

(7) FIG. 6 is a side view of FIG. 2 from the left,

(8) FIG. 7 is a cross-sectional view along the line VII-VII in FIG. 2,

(9) FIG. 7B is an enlarged detail VII of FIG. 7,

(10) FIG. 8 is a front view of the gastric band according to the invention in the closed position and the deflated state, the proximal end of the flexible tube of this gastric band being connected to an inflation/deflation module equipped with a septum,

(11) FIG. 9 is a side view of FIG. 2 in which the gastric band is held flat and in which the inner wall has been omitted in order to show the inner face of the outer wall of the gastric band and, in particular, the anti-collapse grooves provided on said inner face,

(12) FIG. 10 is a longitudinal sectional view along the line X-X in FIG. 9,

(13) FIG. 11A is a front view of a radiopaque insert intended for the gastric band according to the invention,

(14) FIG. 11B is a side view of FIG. 11A,

(15) FIG. 12A is a bottom view (inner wall) of the gastric band according to the invention, open at its distal end and prior to completion, and also of the radiopaque insert from FIGS. 11A & 11B prior to its introduction into the gastric band,

(16) FIG. 12B is a view of FIG. 12A after the introduction of the radiopaque insert from FIGS. 11A & 11B into the gastric band.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

(17) The gastric band according to the invention is designated by the general reference sign 1 on the attached figures.

(18) This inflatable gastric band 1, adjustable around a segment of the digestive tract in order to narrow the latter by constriction, has a hollow flexible band 2 produced from a resilient material, for example a silicone elastomer. This hollow band 2 is elongate and has a substantially rectangular shape in cross section. This hollow flexible band 2 has a substantially rectilinear part 13 having a proximal end 13P, then a curved part 14, which is continued by a substantially rectilinear part 15 having a distal end 9.sup.d and carrying closure means 11.

(19) The proximal end part 13P of the hollow flexible band 2 is connected to a flexible inflation tube 5 and more precisely to the rectilinear part 16, with distal end 6.sup.d, of said flexible tube 5 equipped with closure means 10 matching the closure means 11 of the flexible hollow band 2, which are preferably carried on the outer wall of the distal rectilinear part of the hollow band.

(20) The flexible inflation tube 5 has a free proximal end 7.sup.p intended to be connected to inflation means 8, which themselves comprise an inflation module 80 shown in FIG. 8, are equipped with a septum and permit the injection of inflation liquid or the aspiration of inflation liquid with the aid of a syringe.

(21) The Hollow Flexible Band 2:

(22) The hollow flexible band 2 comprises an inner wall 17 and an outer wall 18 connected to each other by two lateral walls 19 and two end walls, being respectively a proximal end wall 130 and a distal end wall 90, which define a substantially parallelepipedal chamber 30.

(23) This hollow band 2 has the general shape of a hook with a preformed curved part 14, for example substantially circular, characterized by an angular sector S of between 320 and 310 defined, from the center of the circular part, between the proximal end 13.sup.P and the distal end 9.sup.d of the band 2.

(24) As regards the circular preformed curved part itself, its angular sector S.sup.1, which extends between the intersection of the axis VII-VII with the hollow band 2 at the end of the area 13 with proximal end 13.sup.P and the start 20 of the part 15 with free distal end 9.sup.d of this band 2, is between 180 and 270.

(25) Moreover, the axis of the rectilinear part 15, with free distal end 9.sup.d, of the hollow flexible band 2 intersects the rectilinear part 16, with distal end 6d, of the flexible tube 5, in such a way as to make it easier for the surgeon to wind the hollow band 2 around the stomach.
As is shown in particular in FIG. 10, the inner face of the outer wall 18 has parallel longitudinal grooves 25, and two parallel transverse grooves 26 located at the ends of this inner face. Moreover, an inflation opening 4 connecting the flexible tube 5 to the interior of the hollow flexible band 2 is formed in the outer wall 18 close to the proximal end 13.sup.P. The transverse groove 26 provided at this end is arranged on each side of the opening 4, likewise the nearby terminal parts of the longitudinal grooves 25. These grooves 25, 26 make it possible in particular to prevent occlusion of this opening 4 during deflation as a result of a reduced-pressure phenomenon applying the inner wall 17 against the opening 4 in order to close it.

(26) In this example, the closure means 11 arranged on the outer wall 18 of the hollow flexible band 2 are preferably in the form of loops 11.sub.1, 11.sub.2. These loops are preferably at least two in number. It is of course possible to provide other suitable means to ensure proper closure of the gastric ring.

(27) Moreover, still according to the example illustrated, and in order to promote this passage of the flexible tube and to reduce as far as possible the forces needed for this surgical maneuver, the loops have, on their inner face, a series of striations which reduce the contact surface of the flexible tube with the corresponding loop, so as to reduce the frictional forces. These striations extend parallel to the longitudinal axis of the hollow flexible band 2 and in the direction of introduction of the flexible tube 5.
The hollow flexible band and the loops that it carries are made in one piece, that is to say they form a single component.
As can be seen in FIG. 3, the distance between the loops (measured between the proximal end of the proximal loop 11.sub.1 closest to the proximal end 13.sup.P of the band and the distal end of the distal loop 11.sub.2 closest to the distal end 9.sup.d of the band) carried by the rectilinear part of the distal part of the hollow flexible band is approximately 38 mm. This represents approximately 21% of the total length of the inner wall of the hollow band measured between the proximal end 13.sup.P and the distal end 9.sup.d.

(28) The hollow flexible band 2 also has two parallel longitudinal radiopaque bands 21 near the longitudinal edges 22 of the outer wall 18. As is shown in FIG. 5, a radiopaque band 24 is also provided on the proximal transverse edge of the hollow flexible band 2.

(29) It will be noted that these longitudinal edges 22, and also the corresponding edges 23 of the inner wall 17 of the hollow flexible band 2, are blunted, even rounded, so as not to present sharp angles liable to injure the patient.

(30) The hollow flexible band 2 has the characteristic of having an outer wall 18 produced from an elastomer material M1, for example biocompatible silicone, with a hardness D1, while the inner wall 17 is produced from an elastomer material M2, for example biocompatible silicone, with a hardness D2 lower than D1. In practice, D1 is equal to 0.5D2, for example. The outer wall 18, thus reinforced, permits better control of the stomach restriction during the inflation of the hollow flexible band 2 placed in a stable manner around the stomach.

(31) The hollow flexible band 2 is produced by molding in one piece with the two constituent materials M1 and M2: M1 for the outer wall 18, having at least two loops in the distal rectilinear part of the hollow flexible band, and M2 for the inner wall 17, although there can also be a third material M3 corresponding to the parallel radiopaque longitudinal bands 21 and to the radiopaque transverse band 24.

(32) The Flexible Tube 5

(33) The distal end 6.sup.d of the flexible tube 5 is connected to the hollow flexible band 2 by way of the inflation opening 4 formed in the outer wall 18.

(34) In addition, the flexible tube 5, in its rectilinear part 16 with distal end 6.sup.d, is equipped with means for looped closure by slip knot, which means are complementary to those 11.sub.1, 11.sub.2 of the rectilinear part 15, with distal end 9.sup.d, of the hollow flexible band 2. The closure means 10.sub.1, 10.sub.2 are dovetailed notches whose bases 10.sub.1b and 10.sub.2b are of different widths 1.sub.1, 1.sub.2. The width 1.sub.1 of the notch 10.sub.1 nearest to the distal end 6.sup.d is less than the width 1.sub.2 of the other notch 10.sub.2.

(35) According to one variant, these widths 1.sub.1, 1.sub.2 can be equal.

(36) Once the flexible tube 5 is engaged through and beyond the loops 11.sub.1, 11.sub.2, the bases 10.sub.1b and 10.sub.2b of the dovetails 10.sub.1 and 10.sub.2 are in non-return abutment against the arches 11.sub.1, 11.sub.2, in such a way as to lock the hollow flexible band 2 in a ring shape in the closed position, as is shown in FIG. 8.

(37) To further reduce the force needed for the passage of the flexible tube 5, it is also conceivable for the outer surface of the latter to be covered with a coating having a low coefficient of friction.

(38) The proximal free end 7.sup.p of the flexible tube 5 can advantageously be closed off by a stopper of conical shape, which prevents introduction of material into the catheter channel and facilitates the introduction of the catheter into the loops 11.sub.1, 11.sub.2 during the closure of the hollow flexible band 2 in order to form the ring. After formation of the ring, the surgeon removes the stopper and connects the flexible tube to the inflation means 8.

(39) The Inflation Means 8:

(40) As is shown in FIG. 8, the inflation means 8 are composed of a chamber 80 with implantable catheter, provided with a septum 81 through which a needle can be placed for puncturing and injecting inflation fluid.

(41) The implant according to the invention can be put in place by laparoscopy. To help the surgeon, optical locating means are provided on the hollow flexible band 2 and/or on the flexible tube 5.

(42) Alternative Embodiment with Radiopaque Insert:

(43) According to this variant, the gastric band 1 in question comprises a radiopaque insert 40 lodged in the hollow flexible band 2, said insert 40 preferably having a continuation 41 of at least one of the walls 17-18-19-90-130 of the hollow flexible band 2, and still more preferably a continuation 41 of the distal end wall 42 of the hollow band 2. According to a particularly preferred form of this variant, the gastric band 1 is obtained from an intermediate molded component 1, which is removed from the mold through an opening 91 provided in place of the distal end wall 42 of the hollow flexible band 2, said distal end wall 42 being fixed to the intermediate molded component 1 after demolding, and the distal end wall 42 preferably forming one of the ends of a radiopaque insert 40 lodged in the hollow flexible band 2.

(44) In this preferred form of the variant, the radiopaque insert 40 is composed of a base 42 having a continuation 41, as is shown in FIGS. 11A-11B-12A-12B.

(45) The base 42 of the insert 40 can be made from silicone elastomer, for example, while the continuation 41 extending from this base 42 and forming the actual radiopaque part is made from a silicone elastomer charged with a radiopaque material, for example barium sulfate.

(46) As is shown more clearly in FIG. 11A, the continuation 41 is composed, for example, of two parallel rods 43 integrally connected to the base 42 at one of their ends and connected to each other at the free end 44 of the continuation 41. A spacer 45 interconnects the rods 43 of the continuation 41. This radiopaque insert 40 shown in FIGS. 11A-11B can be introduced inside the hollow flexible band 2 of the gastric band 1 via a demolding opening 91 provided on an intermediate molded component 1, precursor of the finished gastric band 1.

(47) Once introduced into the chamber 30 inside the hollow flexible band 2, the continuation 42 is independent of the hollow band 2, while the base 42 of the insert 40 forms a stopper for closing the opening 91, in order to form the distal end wall 90 of the hollow flexible band 2.

(48) The base 42 (or stopper) can be fixed to the hollow flexible band by any suitable means, for example adhesive bonding, welding, etc.

(49) The continuation 43 advantageously has a length less than that of the chamber 30 of the hollow flexible band 2, so as not to obstruct the inflation opening 4.

(50) Once the hollow chamber 30 is filled with inflation fluid, the continuation 43 of the insert 40 is immersed in the fluid filling this chamber 30 of the hollow flexible band 2.