Balloon dissecting instruments

ES 2 208 902 T3

DESCRIPTION

Balloon dissection instruments.

The invention relates to surgical apparatus according to the preamble of claim 1.

Numerous surgical procedures have been developed to replace arteries that have become clogged due to disease. Coronary artery bypass surgery is perhaps the most important of these bypass operations. The coronary arteries supply blood to the heart. As a result of aging and disease, the coronary arteries can become clogged by plaque deposits, stenosis, or cholesterol. In some cases, these obstructions can be treated with atherectomy, anginoplasty, or stenting, and coronary bypass surgery is not required. Coronary artery bypass surgery is required when these other means of treatment cannot be used or have failed to clear a blocked artery. In coronary artery bypass surgery, a vein is taken from somewhere in the body and grafted between the aorta and the coronary artery, below the point of blockage. An illustration of this surgery is shown in figure 1, in which the heart 1, the right anterior coronary artery 2 and the left anterior coronary artery 3 supplying blood to the heart can be seen. As can be seen, the right anterior coronary artery 2 is obstructed in its proximal segment in 2a. In this obstruction, a bypass was applied by grafting a vein segment 4 between the aorta 5 and the distal segment 2b of the right anterior coronary artery 2. Similarly, the left anterior coronary artery 3 may be obstructed, and may require a bypass with a piece of vein 4a between the aorta and the distal segment 3b of the left anterior artery. The operation requires access to the heart, which means that the chest cavity must be completely opened.

Coronary artery bypass surgery requires a piece of vein or artery for grafting. It is preferred to use a vein taken from the patient undergoing bypass surgery. The patient is a reliable source of suitable veins that will not be rejected by the body after transplantation and grafting in the aorta and coronary artery. The saphenous vein in the leg is the best substitute for small arteries such as the coronary arteries, and is the preferred vein to use in coronary artery bypass surgery. This is because the saphenous vein is normally 3 to 5 mm in diameter, which is roughly the same diameter as the coronary arteries. Also, the venous system of the legs is abundant enough, so that once the saphenous vein is removed, other veins remain in the leg that serve to provide adequate return flow of blood. The cephalic vein in the arm is an alternative sometimes used.

A typical operation that was previously required to remove the saphenous vein can be seen in Figure 2. The surgeon cuts the leg to gain access to the saphenous vein and then cuts the vein in the leg. To expose the saphenous vein 6, the surgeon makes a series of incisions from the groin 7 to the knee 8 or ankle 9, leaving one or more bridges of skin 10 along the incision line. Some surgeons make a continuous incision from the groin to the knee or ankle. Manipulation of the vein should be minimal, but the vein must be removed from the connective tissue. Once the vein is exposed, the surgeon grasps it with his fingers while removing the surrounding tissues with dissecting scissors or other scratching instruments. The surgeon uses his fingers and blunt dissecting tools to grasp and lift (or mobilize) the vein from the surrounding tissue. The vein is moved or stretched as far as possible through each incision. To get under the skin bridges, the surgeon lifts the skin with retractors and frees the vein. While removing the vein, the surgeon will find several tributary veins feeding into the saphenous vein. These tributaries must be linked and separated. To separate and ligate tributaries that are under the skin bridges, the surgeon may need to cut one end of the saphenous vein and pull it under the skin bridge to gently pull the vein out from under the skin bridge until the tributary it is exposed enough to be able to be tied and separated. Once the vein has been fully mobilized, the surgeon cuts the proximal and distal ends of the vein and removes the vein from the leg. After being removed, the vein is prepared for implantation at the graft site, and the long incisions made in the leg are sewn together.

The above procedure can be used to cut veins for a femoral popliteal bypass, in which a bypass is formed in a blocked femoral artery from above the occlusion to the popliteal artery, near the level of the knee. The procedure can also be used to remove veins for revascularization of the superior mesenteric artery that supplies blood to the abdominal cavity and intestines. In this case, the severed vein is inserted between the aorta to the distal and patent (unblocked) section of the mesenteric artery. For lower propliteal branch bypass grafts in the calf, the procedure can be used to cut the umbilical vein. The severed vein can also be used for a vein loop in the arm (for dialysis) between the cephalic vein and the brachial artery.

As can be seen from the previous description, the vein cutting operation is very traumatic in itself. In the case of coronary artery bypass, this operation is carried out immediately before the operation with the open rib cage required to graft the cut vein into the coronary arteries. The vein cutting operation is often the most difficult part of the operation. Long incisions made in the leg can be slow to heal and very painful. Complications from the vein removal operation can also prevent the patient from recovering from the entire operation.

The vein removal method presented here is performed with laparoscopic procedures. This allows the vein to be removed in an operation that only requires small incisions. Endoscopic surgical techniques are now common for operations such as gallbladder removal and hernia repair. The surgeon performing the operation makes small incisions and inserts long tools, including forceps, scissors, and staplers, into the incision and deep into the body. By viewing the tools through a laparoscope or video screen of the laparoscope, the surgeon can perform a wide variety of maneuvers, including cutting and suturing, necessary for a wide range of procedures and

ES 2 208 902 T3 surgical operations.

Minimal invasive procedures have been proposed for vein removal. US Patent No. 5,373,840, Knighton, entitled "Endoscope and Method for Vein Removal", shows a method of cutting the saphenous vein at one end, and grasping the vein with clips or forceps, then slide a ring over the vein while it is being held. Knighton uses a dissecting tool with a cutting annular ring, and it is required that the saphenous vein be progressively taken or bypassed with the dissection tool and endoscope, so that once the endoscope is inserted as far as possible, the entire dissected portion of the vein has been stretched into the lumen of the endoscope. As Figures 1 and 10 of Knighton show, the method requires deployment of the forceps within the annular dissecting loop, and requires deployment of the loop and fasteners within the lumen of the endoscope. The blood vessel must be cut and grasped with the forceps before it can be dissected by the dissecting ring.

Patent EP-0-492,361 describes a fixed wire catheter, for anginoplasty procedures, provided with an inflated balloon at the distal end that does not tend to wind up on itself.

US-A-4,702,252 describes a dilatation catheter provided with a shaft comprising a tube of braided material encapsulated over most of its length.

US-A-5,496,276 describes an inflatable balloon for a catheter that has a triple configuration when deflated.

The device described herein allows the surgeon to remove or dissect veins along elongated structures without making long incisions in the skin to access the structure, as was previously required. The present device allows to use minimally aggressive procedures that, in the case of extraction of a saphenous vein, only needs to make two small incisions, one at each end of the saphenous vein. The procedure is carried out with a laparoscopic instrument under the guidance of a laparoscope.

According to the invention, this is achieved by virtue of the features set out in the characteristic part of claim 1. Other advantageous embodiments are described in the other claims.

In a first embodiment, a balloon loaded blunt dissector, having an elongated balloon of any suitable length which may be formed of an elastic or non-elastic material. The balloon may have a double-walled construction and be provided with a central lumen that can receive a guide rod, scope, or other surgical instrument. The apparatus may have a support tube attached to the inner wall of the balloon to provide columnar support for the apparatus. The support tube receives the guide rod, scope, or other surgical instrument and may have a stop member to transmit the thrust force applied to the guide rod or scope to the thrust force of the apparatus. Using the guide rod or scope as a push member, the apparatus can be advanced along the vessel to be dissected free of attached tissue. A balloon cover, which may be elastic or recoverable, is provided to encircle the balloon and facilitate compression of the balloon once deflated.

In another embodiment of the invention there is another balloon push dissection device that can also use an elongated balloon. In this embodiment, the balloon may have a central lumen to accommodate a scope or other laparoscopic instrument. The apparatus has a guide tube that receives a guide rod with a thin metal rod and a flared tip. The guide rod is used as a push member. In this embodiment, there may also be an elastic cover of the balloon designed to compress said balloon when it is deflated.

In yet another preferred embodiment of the invention, a push balloon dissection apparatus may have an elongated balloon disposed on an elongated stem or tubular member, such that said stem or tubular member is within the interior space of the balloon. The balloon dissector can be advanced within the planes of tissue to be dissected and then inflated to create a tunnel through a vessel or other elongated structure. The balloon can then be deflated in series, to be advanced and re-inflated to widen the tunnel. When the apparatus carries a tubular member, it is possible to insert a laparoscope into the hole in the tubular member and use it as a push member to advance the apparatus and facilitate observation of the procedure. In this embodiment, an elastic balloon cover may also be used to aid in deflating and compression of the balloon to facilitate redeployment of the apparatus.

The apparatus described here uses an elongated tubular balloon to dissect a tunnel along the vein to be extracted. The elongated balloon can be wrapped around a guide rod or endoscope and inserted through a small incision in the leg, being pushed along the vein to create a small tunnel in the vein. The elongated balloon may be provided with a balloon cover consisting of a separate removable cover or attached to the balloon. When the balloon is in place next to the vein to be removed, the removable balloon cover (if present) can be removed and inflated the balloon to widen the tunnel and create a working area for insertion of endoscopic instruments. The guide rod or endoscope can be pulled out to allow passage of other endoscopic instruments into the tunnel through the balloon.

In accordance with the invention, the surgeon makes a small incision at each end of the saphenous candle. After the incisions are made, the surgeon inserts a tunneling instrument, or blunt dissector carrying a long balloon, into one of the incisions and advances or pushes it along the saphenous vein to form a small tunnel along the saphenous vein. The surgeon then inflates the long balloon to widen the tunnel. Once the tunnel is widened to the proper size, the surgeon removes the balloon and closes both ends of the tunnel. The surgeon can then inject carbon dioxide into the tunnel, at a sufficient pressure (usually 5 to 15 mm Hg) to inflate the tunnel and create space for the laparoscopic instruments. The surgeon then inserts a laparoscope through the closure to provide a view of the procedure, and inserts a laparoscopic device to remove the vein, such as one of the snag removal devices in the

ES 2 208 902 T3 vein described in accompanying US application no. 08 / 444,424, entitled “Methods and Devices for Blood Vessel Harvesting,” into the leg to dissect connective tissue from the vein, identify lateral branches, and remove the vein from the leg. The description of the aforementioned application no. 08 / 444,424 is incorporated in its entirety by reference. Once the vein is released or dissected from its channel in the leg, the surgeon can cut the proximal and distal ends of the vein and easily remove the vein from the leg. The small incisions in the skin are sewn together so they can heal. The small incisions heal much faster, with fewer complications and significantly less pain, than the open procedures currently in use.

Figure 1 is a front view of the heart showing a vein grafted from the aorta to the right anterior coronary artery, bypassing the proximal segment of the right anterior coronary artery;

Figure 2 is a view of the leg, showing the incisions necessary to extract the saphenous vein, using a traditional open procedure;

Figures 3, 3a and 3b are views of the leg, showing the incisions necessary to extract the saphenous vein, according to the methods presented here;

Figure 4 shows a balloon dissector according to the invention, deflated and ready for insertion;

Figure 5 shows a balloon dissector according to the invention, in its inflated state;

Figure 6 is a cross section of an alternative embodiment of a balloon dissector according to the invention, in a deflated state;

Figure 7 is an isometric view of a balloon dissector in accordance with the invention, showing the balloon dissector in its expanded state;

Figure 8 is a view of the balloon dissector shown in Figure 7 with an elastic balloon cover surrounding the elongated balloon;

Figure 9 is a symmetrical view of another embodiment of a balloon dissector according to the invention, with display capability, shown in its expanded state; Y

Figure 10 is a view of the balloon dissector shown in Figure 9, with an elastic balloon cover surrounding the elongated balloon.

Figure 4 shows an embodiment of a balloon-loaded blunt dissector balloon 15 in its deflated state, with a balloon 16 positioned within the device. Balloon 16 is a cylindrical or tubular non-elastic balloon or balloon with a central lumen 17. Balloon 16 has two walls 18 and 19 and can be described as a double-walled tubular balloon. Balloon 16 can be made of polyethylene, polyurethane, polyamide, or other non-elastic materials, as well as latex or other elastic materials. Balloon 16 can be of any suitable length, for example 12 to 24 inches, to provide a tunnel of convenient length to remove the saphenous vein. Balloon 16 can be of any convenient diameter or width, for example 2 to 3 inches, so that laparoscopic instruments can be placed and properly operated within the tunnel created by balloon 16. Tubular balloon 16 can have a cross section of any suitable shape.

A guide rod 20 with a blunt or rounded tip 21 is placed in the central lumen 17 of the double-walled tube of the balloon 16. The guide rod 20 is used as a pushing member for the balloon 16 through the tissue of the body. . A support tube 22 may exist to provide some columnar support to the device and form a stop or coupling member capable of translating the pushing force applied to the guide rod 20 to the pushing action on the balloon tube 16. Support tube 22 may be attached to the inner wall of balloon tube 16 in any suitable manner. Support tube 22 may have a hanging lip 23 that obstructs the passage of guide rod 20 or endoscope 29 (if present). Alternatively, guide rod 20 or endoscope 29 may be provided with a stop collar 30 that engages support tube 22 (as seen in Figure 5). Support tube 22 may have a square tip 25, as in Figure 4, or a rounded tip 26, as seen in Figure 5. Guide rod 20 and support tube 22 are used to push the balloon 16 along the saphenous vein or other desired passage between the tissue layers. The use of the support tube 22 allows the guide rod 20 or endoscope 29 to be accommodated, if it is used as a pusher member removably in the apparatus 15. This allows the apparatus 15 to utilize relatively expensive and non-disposable devices, such as the endoscope, as push members. If visualization is not required or desired, balloon 16 can be sealed to a disposable push member and attached to the push member with adhesive, heat seal or integral construction, or any other attachment system. A balloon cover 27 surrounds the balloon tube 16 and provides a protective sheath during placement of the balloon-loaded dissector 15. The balloon cover 27 may consist of a thin sheath of polyethylene or other plastic film, or it may consist of a more rigid tube made of PVC, PTFE, PETG, polyethylene or other plastic.

Balloon cover 27 may be resilient or recoverable to serve to compress balloon 16 so that balloon 16 automatically and rapidly collapses once deflated. The balloon cover 27 can be made to regain its shape by choosing an elastic material such as a thin polyethylene sheet that is quite recoverable and elastic under the pressure used to inflate the balloon 16. The balloon 16 itself can also be made of polyethylene, and consist of a thick polyethylene that is not elastomeric under the range of pressures used to inflate the balloon 16. If the balloon 16 and the cover of the balloon 27 are of the same material or of a Mixable, balloon 16 can be heat sealed to balloon cover 27 at various points to prevent balloon cover 27 from inadvertently slipping off balloon 16. When the balloon 16 and the balloon cover 27 are made of different material or materials that cannot be mixed, it is possible to fix them with adhesive or using other appropriate fixings.

In the preferred embodiment of a method for using the devices described herein, the surgeon uses a balloon-loaded dissector to create a working space under the skin and above the saphenous vein appropriate for laparoscopic techniques. The surgeon makes one or more incisions, as can be seen in figure 3, to expose the vein

ES 2 208 902 T3 saphenous. These incisions are called cuts. An incision in the knee 12, an incision in the groin 13, or an incision in the ankle 14 can be used. In figure 3 the saphenous vein 6 can be seen through cuts 12, 13 and 14. It is evident from the description that the use of three or four incisions to remove the entire saphenous vein is purely a matter of convenience, and those especially experienced in laparoscopic procedures may require fewer incisions and smaller incisions than depicted. After insertion, the balloon-loaded blunt dissector 15 is pushed along the blood vessel until the balloon tube 16 lies over the desired length of the saphenous vein. Once in place, balloon 16 is inflated via inflation tube 28. As can be seen in Figure 5, the outer walls are expanded by inflation and the balloon cover 27 is stretched as the balloon 16 swells up. The expansion of balloon 16 widens the tunnel. The outer diameter of the balloon tube 16 defines the size of the tunnel being created, and that outer diameter can be controlled during manufacture and during inflation. As can also be seen in Figure 5, the guide rod 20 can be conveniently replaced by an endoscope 29, which also serves as a thrust member. It is possible to choose the endoscope 29 with an outside diameter that matches the support tube, or it can be provided with a stop collar 30, both constructions serving to couple the endoscope 20 to the balloon tube 16, so that when pushing the endoscope 29 balloon 16 is pushed into the body.

By deflating the balloon 16, through the inflation tube 28, the balloon cover 27 serves to compress and collapse the balloon 16, crushing the inflation fluid out of the balloon 16, so that the balloon 16 again assumes the state The collapsed balloon shown in Figure 4. Once the balloon 16 is collapsed by the elastic force of the balloon cover 27, the device 15 can be further advanced or retracted into position within the body, and repositioned in another area of ​​interest. When the balloon 16 is repositioned, it can be inflated again to widen the tunnel. In this way, the balloon 16 can be inflated and deflated repeatedly. Alternatively, the balloon cover 27 can be removed by pulling it close to the incision to allow expansion of the balloon 16.

Figure 6 shows an alternative embodiment of a balloon loaded blunt dissector. The guide rod 31 is provided with a thin metal rod 32 equipped with a flared tip or olive tip 33. If desired, the guide rod 31 can be replaced by a viewing scope. The balloon is a thin cylindrical balloon, with or without a central lumen. There is a guide tube 35 attached to the outside of the balloon 34 and the guide rod 31 is housed through the guide tube 35. In figure 1, balloon 34 is deflated, with balloon 34 and guide tube 35 shown inside the cover of balloon 27. Balloon 34 of figure 6 is used in the same way as balloon 16 of figures 4 and 5 .

In use, the apparatus is slid over an endoscope (if used) or guide rod 31 and the balloon cover 27 is slid over the apparatus. The use of an endoscope is expected to be preferred as it allows visualization of the anatomy as the distal tip of the apparatus pushes through the layer of fat covering the saphenous vein. The device is either inserted directly into the incision or inserted through a cannula. Once the guide rod 31 and balloon 34 are in place over the blood vessel, the balloon cover 27 can be removed from the incision, and provided with a weakened section to facilitate removal. The balloon cover 27 can be gradually retracted when the balloon 34 is inserted to reveal that part of the balloon 34 that is within the body, and the balloon 34 can be deflated to dissect a wider tunnel in the early stages of insertion. Balloon cover 27 can also be left in place and, if made of elastic material, can serve to compress balloon 34 once deflated to facilitate repositioning of the assembly.

After complete insertion, in a preferred method of use, balloon 34 can be left in place within the tunnel while the endoscope is used to view the interior surfaces of the body at the tip of the apparatus, as shown in Figure 3a. If the balloon 34 is provided with a central lumen, endoscopic instruments can be passed through the central lumen in order to perform surgical procedures on parts of the body such as the saphenous vein and communication veins of the leg. In situations where it is convenient to inflate the tunnel created by the balloon 34, said balloon 34 can be deflated and removed from the tunnel through the cut 13, and blow a cannula door 34 with the inflation tube 37 into the same cut, as it appears in Figure 3b. A second secondary endoscope access port 38 may be inserted into knee incision 12 in order to pass a series of instruments into the workspace.

The phase of removal of the balloon cover 27 can be avoided if said balloon cover 27 is perforated along a series of longitudinal lines and sealed to the balloon 34 along longitudinal lines, so that the expansion of balloon 34 tears the balloon cover 27 to allow for expansion, but the pieces remain attached to the balloon 34 so that they can be easily removed.

Another embodiment of a balloon dissection apparatus 50 is shown in FIG. 7. In this embodiment, the balloon dissector 50 includes a handle 52, a rod to form the tunnel 54 which may be provided with a blunt tip. 56, and an elongated balloon 58 having an inflation set 60 extending from balloon 58. The shaft for forming the tunnel 54 is made of a suitable material, such as surgical stainless steel, to give adequate rigidity to the shaft 54 ​​to serve as a blunt plug to form the tunnel between the tissue layers. When balloon dissector 50 is configured as an extraluminal balloon dissector to remove the saphenous vein from the leg, for example, the shaft for tunnel 54 can be about 12 inches long, and about 1/8 inch diameter. . Alternatively, tunnel shaft 54 ​​may be formed of a semi-flexible material, such as plastic, for example, to accommodate situations where it is desirable to have a tunnel shaft capable of navigating somewhat tortuous passages within the body. Tunnel shaft 54 ​​can be mounted to handle 52 using any suitable attachment system, for example by gluing or a compression fit. The blunt tip

ES 2 208 902 T3

56, which may be formed integrally with the shaft of the tunnel 54 or be a separate member, provides a blunt distal end on the shaft of the tunnel 54. Although an olive-shaped tip 56 is shown, other shapes are possible offering a blunt surface. The blunt tip 56 can also be omitted.

An elongated balloon 58 has distal and proximal ends 59 and 53, and a neck portion 57 extending from the proximal end 53 of balloon 58. For the purposes of this application, an elongated balloon is used which is defined as a balloon that it has an axial length substantially greater than its transverse diameter when the balloon is deflated. As shown in Figure 7, the elongated balloon 58 is mounted on the axis of the tunnel 54 so that the axis of the tunnel 54 lies within the interior space 63 of the balloon 58. Preferably, the distal end 59 of the balloon 58 is provided with a nipple or pocket 61 that mates with the distal tip 56 of the tunnel shaft 54 ​​to facilitate protection against stretching or tearing of the distal tip of the balloon during tunnel formation. As will be described below, this construction allows tunnel shaft 54 ​​to be used as a push member to advance deflated balloon 58 along a blood vessel or other elongated structure, if desired, to release connected tissues.

The neck portion 57 of the balloon 58 may be fixed within the handle 52 in a fluid-tight manner. Alternatively, the neck portion 57 may be attached to the tunnel shaft 54 ​​by means of any suitable attachment system such as gluing or clamping. When the neck portion 57 is mounted within the handle 52, as indicated in FIG. 7, the balloon inflation kit 60 may extend from the neck portion of the elongated balloon 57 to provide a fluid passage within the balloon. interior space 63 of globe 58.

An example of a suitable group for inflating the balloon is shown in Figure 7 in the form of a kit for inflating the balloon 60. The kit for inflating the balloon 60 includes a tube 68 that extends from the balloon 58 and is connected to a Y connection 70. There is a check valve fitting 67 connected to one port of the Y connection 70, and an evacuation fitting 69 connected to the other port of the Y connection 70. There is a clamp 66 to close the passage of fluid from the Y connection 70 to the evacuation fitting 69. The equipment for inflating the balloon 60 shown is of the same type described in the attached application no. 08 / 570,766, filed December 12, 1995, the entire disclosure of which is incorporated by reference. Of course, numerous other groups are possible for inflating the balloon.

In the example of Figure 7, the elongated balloon 58 is inflated by closing the clamp 66 and injecting an appropriate inflation fluid, preferably a saline solution, although other fluids, such as air, inserted through the connection 67 may be used into of the inflation lumen of balloon 68, which is in communication with interior space 63 of balloon 58.

As an alternative to the kit for inflating balloon 60, handle 52 may be provided with an inflation port communicating with the proximal end of neck portion 57 of elongated balloon 58. In this alternative embodiment, the injection fluid is injected , through the swollen door on the handle

52, directly inside the neck portion 57 of the balloon 58.

Preferably, the balloon 58 is made of a suitable medical grade non-elastomeric material such as a polyurethane using known manufacturing techniques to have a predetermined elongated shape. While all non-elastomeric materials exhibit some degree of elasticity, for the purposes of this application, a non-elastomeric material is one that remains substantially non-elastic at the desired degrees of swelling used for the particular process. While an elastomeric balloon can be used with the balloon dissector 50, it is preferable to use a non-elastic balloon so that the expansion envelope of the balloon can be more accurately anticipated. In contrast, an elastomeric balloon tends to swell following a path of less resistance to tissue and differences in localization in tissue resistance can cause unwanted aneurism to occur in the balloon causing non-uniform dissection.

In a preferred method of use, an incision is made in the body near the elongated structure within the body that it is desired to dissect from the connective tissue. The surgeon identifies the appropriate tissue dissection planes that he wishes to occur along and the balloon dissector 50 is inserted, either directly or with the aid of a cannula, through the body incision, advancing it following the planes of identified tissue. The surgeon uses the handle 52 and pushes the balloon dissector 50 as a blunt obturator following the ejido planes adjacent to the elongated structure until reaching a desired location for the deployment of the dissector 50. As the dissector 50 is advanced into the body, its progress through the skin by direct observation and / or manual palpation. Depending on the procedure, different amounts of the total length of elongated balloon 58 may be disposed within the incision.

Once the desired position for dissection is reached through the blunt tunnel formation, the elongated balloon 58 can be inflated by closing the clamp 66 and communicating an inflation fluid through the balloon inflation set 60 into the interior space 63 of the balloon. 58. When inflated, balloon 58 expands into the predetermined elongated shape and dissects tissue away from the elongated structure to create a tunnel along the elongated structure. Once the tunnel is created, the dissector 50 can be deflated by releasing the clamp 66 and applying a vacuum to the male evacuation connection 69. Once deflated, the dissector 50 can be withdrawn from the body through the incision, or further advanced to along the elongated structure and re-inflate it to widen the tunnel.

After the dissector is removed from the body, a skin cannula and closure assembly can be inserted, for example of the type described in application no. 08 / 570,766, into the incision and advance the skin closure into the incision to create a substantially gas-tight seal in conjunction with the incision. The space created by balloon dissector 50 can then be inflated with the injection of an appropriate gas through a port provided in the cannula, if an inflated operating space is desired.

The use of dissector 50 specifically contemplates multiple serial balloon dissections. The dissector 50 can be advanced into the body by eta6

ES 2 208 902 T3 passed along the natural planes of dye identified by the repeated advancement and unfolding of the dissector 50 in order to form a tunnel of the desired length along the elongated structure. The process of advancing dissector 50, inflating balloon 58, and deflating balloon 58 can be repeated serially until the desired tunnel is created. In the embodiment of balloon dissector 50 shown in Figure 7, vacuum can be applied to balloon 58 to deflate and contract balloon 58 so that dissector 50 can be repositioned and deployed as required.

Balloon dissector 50 is shown in Figure 8 with an elastomeric balloon cover 72 surrounding elongated balloon 58. In all other respects dissector 50 is identical to the embodiment of Figure 7. Preferably, cover 72 It has a diameter such that when the balloon 58 is in the deflated state, the cover 72 compresses the balloon 58 about the axis 54. Thus, the use of the cover 72 assists in the serial unfolding of the balloon 58 by causing the balloon to automatically return to the compressed state once deflated. The elastomeric cover 72 may be formed of an elastic material, such as a thin polyurethane sheet that is sufficiently recoverable and elastic under the pressure used to inflate the balloon 58, or it may be formed of an elastomer such as silicone rubber or latex.

Cover 72 may be attached to balloon 58 at various points using known bonding techniques to prevent cover 72 from inadvertently slipping off balloon 58. Alternatively, cover 72 may have a diameter that matches the diameter of shaft 54, so that the cover 72 is held in position by its elastic compression on the shaft 54, or by means of friction. Cover 72 can also completely cover elongated balloon 58 and be attached to handle 52. In this case, cover 72 can be inflated independently of elongated balloon 58 to provide a balloon with elastomeric characteristics, ie, localized tissue expansion along the path of least tissue resistance.

As an alternative embodiment, the elongated balloon 58 may be elastic and the cover 72 may be non-elastic, such that the non-elastic cover 72 acts to limit the expansion of the elongated balloon 58.

It is also possible to use a separate removable cover of the type described in pending application no. 08 / 570,766, for example, or an integral balloon cover that separates from the balloon once expanded as described with reference to previous embodiments.

Another embodiment of balloon dissector 80 is shown in FIG. 9. Balloon dissector 80 differs from balloon dissector 50 only in that tubular member 82 replaces tunnel shaft 54 ​​and there is a communicating opening. with the hole in the tubular member 82 provided in the handle 52. In this embodiment, the tubular member 82 serves as an extension of the cover to provide visualization capability to the dissector when used in conjunction with a laparoscope. Tubular member 82 has an inside diameter, for example 10mm, sized to receive a conventional laparoscope. The tubular member 80 can be made of any suitable material, for example plastic.

The tubular member 82 may have an open distal end 84, as shown in FIG. 9, to allow observation with the laparoscope through the open distal end 84. As shown in Figure 9, the open distal end 84 of the tubular member 82 may be cut at a 45 degree angle, for example, and provided with a lip 86 that serves to capture the distal end of the laparoscope when inserted through so that said laparoscope extends beyond the open distal end 84. Alternatively, the open distal end 84 of the tubular member 84 may be square and the lip 86 provided to bend the open distal end inward. The distal end of tubular member 82 may also be closed and rounded if viewing through an open distal end is not desired.

An instrument closure may be provided, which may comprise a reduced inner diameter area in tubular member 82, to prevent balloon inflation fluid from escaping from handle 52 during balloon inflation. Alternatively, or in combination with the reduced diameter area on tubular member 82, an instrument closure of the type depicted in application no. 08 / 570,766.

In addition to the balloon inflation options described with respect to the embodiments of Figures 7 and 8, the elongated balloon 58 of dissector 80 can be inflated by injecting fluid into the balloon through an inflation port in handle 52 directly into the balloon. a lumen in tubular member 82. If tubular member 82 has the currently preferred open distal end construction, inflation fluid may communicate through the hole in tubular member 82 and exit through open distal end 84 into interior space 63 of balloon 58. If a closed-end tubular member 82, inflation may be done through a separate lumen formed in the wall of tubular member 82 that opens into interior space 63 of balloon 58.

To prepare for tunnel dissection, a laparoscope, which for example may be a conventional 10 mm laparoscope, is inserted through handle 52 and advanced into the hole in tubular member 82 until the distal end of the laparoscope is captured by lip 86 at open distal end 84 of tubular member 82. While an angled scope will provide better visualization through the open distal end 84 of the tubular member 82, a straight scope can also be used.

The balloon dissector 80 is then inserted through the incision and a tunnel is smoothly formed following the desired tissue planes using the laparoscope and tubular member 82 as a blunt obturator. The procedure to be followed is the same as previously described with respect to the embodiments of Figures 7 and 8, except that the progress of the operation can be observed through the laparoscope during tunnel dissection. During the tunneling phase, the distal end of the laparoscope looks through the open distal end 84 of the same tubular 82 obstructed only by a simple and preferably transparent layer of the elongated balloon 58. In addition, when the balloon 58 is inflated to create a tunnel along the desired elongated structure, the laparoscope can be used to observe the progress

ES 2 208 902 T3 of dissection.

FIG. 10 shows the addition of an elastic cover 72 to the balloon dissector 80 which is capable of visualization. Cover 72 may have the same construction as described above and function in an equivalent manner to automatically compress elongated balloon 58 against tubular member 82 once deflated.

The balloon devices described here can be used in other procedures in addition to dissection to remove veins. The description of the devices is made in an environment intended for illustrative purposes only. It is clear that the devices and methods can be used to tunnel and expand workspaces in other long body structures. For other operations, various arteries and veins must be exposed and mobilized, such as a popliteal bypass, or a loop for dialysis in the vein. In these operations, a vein must be removed, and the places where the vein will be attached or anastomosed must also be uncovered. Balloon devices can also be used to access any blood vessel, for any type of vascular surgery. For example, communicating veins or perforations in calves can be exposed by dissecting the muscles, deep down, within the calf to expose the blood vessels necessary to perform a Linton procedure laparoscopically. Devices and methods can be used to expose those portions of the arteries where grafts will be placed.

Other vessels can be dissected from the surrounding tissue, such as fallopian tubes, spermatic cords, bile ducts, intestines, and others. These vessels can be dissected and mobilized laparoscopically using the techniques described above. Embodiments of the device can also be used to retrofit a scope with a balloon dissector to dissect through a tunnel under direct vision. Alternatively, the balloon can be used to guide or support a scope within an existing space that needs periodic dilation to allow advancement of the scope. For example, a colonoscope can be fitted with the balloon dissector described here and the device used to facilitate insertion of the colonoscope into the colon, especially around the splenic flexure, by inflating the balloon as the tip of the colonoscope approaches the splenic flexure. . A uteral scope can be equipped with the balloon dissector described here to facilitate insertion of the scope into the urethra, which often requires dilation prior to insertion of a scope. The devices described can be used as an anchor in combination with any scope, since while inflated it serves to hold the scope in place within the body. Although the preferred embodiments of the devices and methods have been described, they are merely illustrative of the principles of the invention. Other embodiments and configurations may be envisaged without thereby departing from the scope of the appended claims.