VEIN SUTURE COLLAR

Abstract: A vein suture collar (10) for anchoring an electrode lead to a vein in which the lead is inserted includes a sleeve member (12) having three longitudinally spaced circumferential suture grooves (26,28,30) in the exterior surface (18) and a raised web area (32,34,36) formed on the inte­ rior sleeve surface (24) radially inward of each groove (26,28,30). The three raised web areas (32,34,36) are angularly spaced about the sleeve axis (16) and a longitudinal slit through the sleeve thickness can be provided. The slit collar can be separated at the slit and used to enclose the portion of the vein having the inserted electrode.

Description: BACKGROUND OF THE INVENTION Field of the Invention: The present invention relates to suture collars for use in ligating veins with inserted electrodes, to firmly tie the vein to the electrode, and a method of installation. Description of the Prior Art: It is well known that damage can occur to both polyurethane and silicone electrode leads if a suture is tightly tied around the body of the electrode lead. To avoid damage to the lead body, manufacturers have developed a variety of suture collars. There are three basic types of suture collars available on the market. The simplest, which is depicted in Figs. 1A and 1B, is a silicone tube (depicted by the letter "a" in the Figures) which fits over electrode lead body "b" and is partially inserted into vein "c" at the lead entry site "d". Sutures "e" are then tied over the vein, sleeve and lead body. Although not shown, these collars generally have a longitudinal slit to facilitate instal­ lation over the lead body. A slightly more sophisticated collar has a sleeve with a butterfly collar portion which can be anchored to the surrounding tissue. As depicted in Figs. 2A and 2B, collar "f" includes but­ terfly portion "g" with wings "h", "i" which can be folded around vein "c" (Fig. 2B) and tied by suture "j". The third type of collar is a sleeve with a groove formed in the collar exterior surface. As is depicted in Fig. 3, a collar "k" of this type sits in the vein and is anchored by tying suture "l" around groove "m" and vein "c". Problems with conventional suture collars stem from the need to be able to slide the collar along the electrode lead into place at the vein entry site while still providing an anchor for the electrode lead. The bore of the collar typically is made only slightly larger than the outer diameter of the lead. How­ ever, small variations in either the collar inside diameter or the lead outside diameter can result in a situation where exces­ sive interference is present and undue force is required to slide the collar, leading to possible damage to the lead, or a situa­ tion where the collar is too loose and no firm anchor is provid­ ed. Also, in either case the sutures can cut the vein if too much tension is applied, especially in the latter situation if the surgeon attempts to construct the collar by tightening the sutures. SUMMARY OF THE INVENTION In accordance with the present invention, as embodied and broadly described herein, the vein suture collar comprises a cy­ lindrical member having a through-bore along the longitudinal axis thereof, a plurality of circumferential grooves formed in the exterior surface of the member and spaced longitudinally, and a plurality of raised web areas formed on the interior surface of the member and extending radially into the through-bore. Preferably, each of the plurality of raised web areas is lo­ cated to radially oppose a respective one of the grooves. It is also preferred that the raised web areas are angularly spaced about the interior surface of the member. And it is still further preferred that the collar include a slit extending longitudinally along the entire length of the sleeve and radially through the thickness of the sleeve, and that the sleeve is resiliently spreadable at the slit to enclose the vein and the inserted electrode lead. Further in accordance with the present invention, the method of installing a suture collar for use in tying a vein to an in­ serted electrode lead, the collar of the type comprising a cylin­ drical sleeve of a flexible material with a plurality of circum­ ferential grooves in the exterior sleeve surface spaced in the longitudinal sleeve direction, comprises the steps of forming a slit in the sleeve in the longitudinal direction; separating the sleeve at the slit; enclosing the portion of the vein having the inserted electrode lead with the separated sleeve; and closing the sleeve at the slit. The closing step includes the step of applying sutures to each of the plurality of grooves to firmly abut the slit sleeve edges. BRIEF DESCRIPTION OF THE DRAWINGS Figs. 1A and 1B are schematic representations of a conven­ tional suture collar; Figs. 2A and 2B are schematic representations of another conventional suture collar; Fig. 3 is a schematic representation of yet another conven­ tional suture collar; Fig. 4 is a schematic view in partial longitudinal cross section of a suture collar made in accordance with the present invention; Fig. 5 is a schematic end view of the suture collar shown in Fig. 4; and Fig. 6 shows a variant of the suture collar depicted in Fig. 4. DESCRIPTION OF THE PREFERRED EMBODIMENT Reference will now be made in detail to the present pre­ ferred embodiment of the invention, an example of which is illus­ trated in Figs. 4-6 of the accompanying drawings which show a su­ ture collar designated generally by the numeral 10 made in accordance with the present invention. In accordance with the present invention, the vein suture collar comprises a cylindrical member having a through-bore along the longitudinal axis thereof. As embodied herein, and with ini­ tial reference to Fig. 4 of the drawings, suture collar 10 includes cylindrical sleeve 12 having through-bore 14 extending along longitudinal axis 16 of sleeve 12. Sleeve 12 can prefer­ ably be formed from medical grade silicone or any other flexible, bio-compatible low compression set material. Exterior cylindri­ cal surface 18 of member 12 is tapered at opposing longitudinal ends. In the embodiment shown in Fig. 4, interior cylindrical surface 24 of sleeve 12 has a generally constant diameter along longitudinal axis 16, except for the raised web areas to be discussed herein­ after. The I.D. of the collar generally varies from about 0.25 mm to about 0.35 mm larger than the O.D. of the electrode lead, the variation depending upon the stiffness of the lead, insulation material surrounding the lead (polyurethane or silicone) and whether the lead is unipolar or multipolar. Further in accordance with the present invention, the vein suture collar further comprises a plurality of circumferential grooves formed in the exterior surface of the member and spaced longitudinally. As embodied herein, and with continued reference to Fig. 4, a total of three circumferential grooves 26, 28, 30 are formed in exterior surface 18 and spaced along longitudinal axis 16. Grooves 26, 28, 30 should be sized to accommodate and capture the suture thread to be used to ligate the vein. Still further in accordance with the present invention, the vein suture collar includes a plurality of raised web areas formed on the interior surface of the cylindrical member and ex­ tending radially into the through-bore. As embodied herein, and with reference to Figs. 4 and 5, a total of three raised web areas 32, 34, 36 are formed on interior surface 24 and extend ra­ dially into through-bore 14. It is intended that raised web areas 32, 34, 36 provide the primary contact between collar 10 and the inserted electrode. Thus, for applications where collar 10 is to be used in the manner of conventional suture collars where direct contact between the electrode leads and the collar occurs, the interior diameter 24 of the sleeve 12 can be made larger than the outside diameter of the electrode lead by a margin suf­ ficient to preclude interference between the interior surface 24 and the electrode lead. Concurrently, raised web areas 32, 34, 36 should be sized to provide an interference fit with electrode lead to a degree only to inhibit movement of the collar by gravi­ ty alone, while permitting collar 10 to be manually slid along the electrode lead with a small force. The lead-contacting sur­ faces of raised web areas 32, 34, 36 should be smooth and can preferably be made circular and rounded as depicted in the fig­ ures. However, other web area shapes can be used. Preferably, the web areas are spaced longitudinally along the axis of the cylindrical member and are formed radially beneath respective circumferential suture grooves. As embodied herein, and with reference to Figs. 4 and 5, raised web areas 32, 34, 36 are formed at the same longitudinal locations and radially inward of grooves 26, 28, 30, respectively. This correspondence permits the force exerted by the sutures to be radially directed through the web areas 32, 34, 36 to the electrode lead and permit collar 10 to be flexed between these longitudinal locations. It is also preferred that raised web areas be angularly dis­ tributed on the interior surface about the cylindrical member longitudinal axis. As embodied herein, and with reference to Fig. 5, the three web areas of the preferred embodiment are angu­ larly displaced about axis 16 at about 60 degree intervals as shown by the angle designated alpha. This angular distribution acts to force a plurality of contacts between the lead and the interior surface 24 of collar 10. In accordance with the present invention, the vein suture collar further comprises a slit extending longitudinally along the entire length of the sleeve and radially through the thick­ ness of the sleeve. As a result of the flexible sleeve material, the sleeve can be resiliently spread at the slit to enclose both the vein and inserted electrode lead in a preferred installation mode. As embodied herein and as depicted in Fig. 6, collar 10 can include slit 40 in cylindrical sleeve 12 along the longitudi­ nal direction and through the thickness of sleeve 12. Slit 40 permits collar 10 to be used to protect both vein (designated 42 in Fig. 6) and the electrode lead (designated 44) from being damaged by tightening of sutures 46 in grooves 26, 28, 30. Collar 10 with slit 40 can thus be used in a manner dif­ ferent from the conventional suture collars. Specifically, and in accordance with the preferred installa­ tion method of the present invention, installation of the collar is accomplished by separating the flexible collar at the slit and enclosing the vein and inserted lead with the separated collar. Following the enclosing step, the sutures are tied around the circumferential grooves to cause the slit edges of cylindrical sleeve to firmly abut. For applications using a slit collar, the raised web areas can be formed to provide a lesser degree of in­ terference with the electrode lead inasmuch as the raised web areas will not contact the electrode lead directly but through the thickness of the vein wall. It will be apparent to those skilled in the art that various modifications and variations can be made in the vein suture col­ lar of the present invention without departing from the scope or the spirit of the invention. It is intended that the present invention cover the modifications and variations of this inven­ tion provided they come within the scope of the appended claims and their equivalents.

Claims: 1. A vein suture collar comprising: a cylindrical member having a through-bore along the longitudinal axis thereof; a plurality of circumferential grooves formed in the exterior surface of said member and spaced longitudinally; and a plurality of raised web areas formed on the interior surface of said member and extending radially into said through-­ bore. 2. The collar as in claim 1 wherein each of said plurality of raised web areas is located to radially oppose a respective one of said grooves. 3. The collar as in claim 1 wherein said raised web areas are angularly spaced about the interior surface of said member. 4. The collar as in claim 1 having three longitudinally spaced grooves. 5. The collar as in claim 1 having three raised web areas spaced along the longitudinal axis of said member and angularly spaced about the interior surface of said member at about 60 de­ gree intervals. 6. The collar as in claim 1 wherein each of said raised web areas is generally circular in shape. 7. A vein suture collar for enclosing and protecting a vein and an electrode lead inserted in the vein, the collar com­ prising: a cylindrical sleeve formed of a resilient material; a plurality of circumferential suture grooves formed in the exterior sleeve surface and spaced longitudinally; a plurality of raised web areas formed on the interior surface of said sleeve and extending inwards and radially; and a slit extending longitudinally along the entire length of said sleeve and radially through the thickness of said sleeve, said sleeve being resiliently spreadable at said slit to enclose the vein and inserted electrode lead. 8. The collar as in claim 7 having three circumferential grooves and three raised web areas, said web areas being angu­ larly spaced about the interior surface of said sleeve. 9. The collar as in claim 7 wherein each of said raised web areas is formed to radially oppose a respective one of said grooves. 10. In a vein suture collar of the type for anchoring an electrode inserted in a vein to be ligated, the collar having a cylindrical sleeve body with a suture groove circumferentially disposed in the exterior sleeve surface for use in securing the collar, the improvement comprising: at least one additional circumferential suture groove spaced longitudinally from the first groove; the collar having an inside diameter greater than the outside diameter of the vein with the inserted electrode; and means located on the interior surface of the sleeve for providing an interference fit with the electrode at discrete lon­ gitudinal positions along the sleeve. 11. The improved collar as in claim 10 further including a longitudinal slit in the sleeve, the sleeve being resiliently separable at said slit for enclosing the vein portion having the inserted electrode. 12. The improved collar as in claim 10 wherein said means for providing an interference fit includes a plurality of angu­ larly spaced raised web areas extending radially inward of the interior surface. 13. Method of installing a suture collar for use in tieing a vein to an inserted electrode lead, the collar comprising a cy­ lindrical sleeve of a flexible material with a plurality of cir­ cumferential grooves in the exterior sleeve surface spaced in the longitudinal sleeve direction, the method comprising the steps of: a) forming a slit in the sleeve in the longitudinal direction and through the sleeve wall thickness; b) separating the sleeve at the slit; c) enveloping the portion of the vein having the in­ serted electrode lead with the separated sleeve; and d) closing the sleeve at the slit, said closing step including the step of applying sutures to each of the plurality of grooves to abut the slit sleeve edges.

Inventors: MILIJASEVIC, ZORAN, STEWART, SUE
Applicants: TELECTRONICS N.V.
Application year: 1986
Main classification: A61N1
IPC codes: A61B17, A61N1