Detachable tip optical valvulotome

• US 5,284,478 A
• Filed: 06/08/1992
• Issued: 02/08/1994
• Est. Priority Date: 06/08/1992
• Status: Expired due to Term

• Current Assignee: ESC Medical Systems, Ltd (Boston Scientific Corporation)
• Original Assignee: Endovascular, Inc.
• Inventors: Nobles, Anthony A., Cohen, Donald
• Primary Examiner(s): Thaler, Michael H.
• Application Number:
  US07/895,090
• Time in Patent Office: 610 Days
• Field of Search: 606/159, 606/15, 606/16
• US Class Current: 606/159
• CPC Class Codes: A61B 17/12 for ligaturing or otherwise compressing tubular parts of the body, e.g. blood vessels, umbilical cord specially adapted for vas deferens or fallopian tubes A61F6/20; materials for ligaturing blood vessels A61L17/00
• CPC Class Codes: A61B 18/082 Probes or electrodes therefor
• CPC Class Codes: A61B 2017/22097 Valve removal in veins

Abstract

An optical valvulotome having a replaceable blade head for in situ cutting of venous valves has a catheter that can be pushed through a vein. An anchor is attached to the catheter, and a cutting head can be releasably engaged with the anchor to cut the valves as the catheter is pushed through the vein. The cutting head has two spaced apart cutting blades that form a light passageway between the blades. An optical fiber is disposed in the catheter for collecting light from the light passageway between the blades, and the optical fiber is engaged with a display apparatus for displaying a video image of the blades and vein as the catheter is pushed through the vein. The catheter can be retrieved from the vein, and the cutting head easily disconnected from the anchor and replaced with another cutting head having a size larger or smaller than the first head, as appropriate for the changing width of the lumen of the vein.

Claims

1. A valvulotome for cutting venous valves in a blood vessel, comprising:

a catheter sufficiently flexible to follow the contour of the blood vessel when passed through it and sufficiently axially rigid to permit the catheter to be pushed through the vessel, the catheter having a distal end;

an anchor fixedly attached to the catheter near the distal end thereof, the anchor having an open distal end and an opening formed in the anchor;

a cutting head comprising a pair of cutting blades having sharp cutting edges and being shaped to engage and cut through the venous valve cusps when the cutting blades are aligned therewith, the blades being disposed relative to the open distal end of the anchor to provide a light passageway from the open distal end to the interior sides of the blades and adjacent regions within the vein, the cutting head having a proximal segment detachably connected to the anchor near the open distal end thereof, wherein the cutting head defines a longitudinal axis and has two slots opposed to each other on the cutting head and extending generally parallel to the longitudinal axis of the cutting head to establish first and second portions of the proximal segment of the cutting head, the proximal segment of the cutting head being hollow and having an inside surface with a detent formed thereon for engaging the opening of the anchor, wherein the cutting head is biased to an operating configuration, wherein the first and second portions of the cutting head closely engage the anchor and the detent is engaged with the opening, and a replacement configuration established by urging the cutting blades toward each other, wherein the first and second portions are spaced from each other relative to the operating configuration and the detent is distanced from the opening to permit disengaging the cutting head from the anchor; and

a viewing scope mounted within the catheter in light communication with the light passageway for generating an image of the interior sides of the blades and the adjacent regions within the vein to facilitate rotation of the cutting blades to align the blades with the valve cusps.

2. The valvulotome of claim 1, further comprising a key formed on the cutting head and a keyway formed on the anchor for receiving the key of the cutting head therein to prevent rotational movement of the cutting head relative to the anchor.

3. The valvulotome of claim 1, wherein each said cutting blade has:

an external contour, viewed in a plan direction perpendicular to the major outer surface of the blade, which has a rounded tip to blend with a cylindrical outer surface of the cutting head;

an outer edge, viewed side on relative to the plan view, which is flush with the cylindrical outer surface of the cutting head except for a region adjacent the tip which is curved radially inwardly to reduce the risk of gouging the blood vessel in the event of a glancing contact with a wall of the blood vessel; and

a cutting edge extending from the tip radially inwardly within the cutting head, the cutting edges of the cutting blades together defining a generally U-shaped opening.

4. The valvulotome of claim 1, wherein the catheter includes a guide wire lumen, and the guide wire lumen is engageable with a guide wire for pushing the catheter over the guide wire.

5. An apparatus for the in-situ cutting of valves within a blood vein when pushed through the vein in a direction opposite to the normal flow of blood through the vein, comprising:

an elongated catheter having an open distal end with an anchor attached thereto, the anchor having an opening;

a cutting head detachably connected to the catheter such that the cutting head can be selectively engaged and disengaged with the catheter without unduly damaging the cutting head or catheter, the cutting head comprising,

a distal segment having at least a pair of cutting blades spaced from each other, the blades having exterior sides which are contoured to generally follow the curvature of the interior walls of the blood vessel, the blades being disposed relative to the open distal end of the anchor to establish a light passageway from the open distal end to the interior sides of the blades and adjacent regions within the vein; and

a proximal segment having an inside surface and a detent for engaging the opening of the anchor formed thereon, the segment also having first and second longitudinally-extending slots to establish first and second portions of the proximal segment, wherein the cutting head is materially biased toward an operating configuration, wherein the first and second portions of the proximal segment of the cutting head closely engage the anchor and the detent is engaged with the opening, and the cutting blades can be urged toward each other to establish a replacement configuration of the cutting head, wherein the first and second portions are spaced from each other relative to the operating configuration and the detent is distanced from the opening to permit disengaging the cutting head from the anchor; and

an optical fiber mounted on the catheter and having a distal end positioned adjacent the distal end of the catheter for collecting light therefrom, the optical fiber being operably engageable with a viewing apparatus for displaying an image of the interior sides of the blades and adjacent regions within the vein.

6. The apparatus of claim 5, further comprising a key formed on the cutting head and a keyway formed on the anchor for receiving the key of the cutting head therein to prevent rotational movement of the cutting head relative to the anchor.

7. The apparatus of claim 5, wherein each said cutting blade has:

an external contour, viewed in a plan direction perpendicular to the major outer surface of the blade, which has a rounded tip to blend with a cylindrical outer surface of the cutting head;

an outer edge, viewed side on relative to the plan view, which is flush with the cylindrical outer surface of the cutting head except for a region adjacent the tip which is curved radially inwardly to reduce the risk of gouging the blood vessel in the event of a glancing contact with a wall of the blood vessel; and

a cutting edge extending from the tip radially inwardly within the cutting head, the cutting edges of the cutting blades together defining a generally U-shaped opening.

8. The apparatus of claim 5, wherein the catheter includes a guide wire lumen, and the guide wire lumen is engageable with a guide wire for pushing the catheter over the guide wire.

9. An apparatus for the in-situ cutting of venous valves, comprising:

a catheter having axial strength sufficient for pushing the catheter through a vein, the catheter having an optical fiber disposed therein;

a cutting head having a pair of cutting blades and a light passageway therebetween, the cutting head defining a longitudinal axis and having two slots opposed to each other on the cutting head and extending generally parallel to the longitudinal axis of the cutting head to establish first and second portions of the proximal segment of the cutting head, the cutting head also having an inside surface with a detent formed thereon; and

an anchor having an opening and being attached to the catheter for releasably holding the cutting head onto the catheter, the optical fiber being in light communication with the light passageway for collecting light therefrom and directing the light to a display apparatus for displaying a video image of at least a portion of the light passageway;

wherein the cutting head is biased toward an operating configuration, wherein the first and second portions of the cutting head closely engage the anchor and the detent is engaged with the opening, the blades of the cutting head being movable toward each other to establish a replacement configuration of the cutting head, wherein the first and second portions are spaced from each other relative to the operating configuration and the detent is distanced from the opening to permit disengaging the cutting head from the anchor.

10. The apparatus of claim 9, further comprising a key formed on the cutting head and a keyway formed on the anchor for receiving the key of the cutting head therein to prevent rotational movement of the cutting head relative to the anchor.

11. The apparatus of claim 9, wherein each said cutting blade has:

an external contour, viewed in a plan direction perpendicular to the major outer surface of the blade, which has a rounded tip to blend with a cylindrical outer surface of the cutting head;

an outer edge, viewed side on relative to the plan view, which is flush with the cylindrical outer surface of the cutting head except for a region adjacent the tip which is curved radially inwardly to reduce the risk of gouging the blood vessel in the event of a glancing contact with a wall of the blood vessel; and

a cutting edge extending from the tip radially inwardly within the cutting head, the cutting edges of the cutting blades together defining a generally U-shaped opening.

12. The apparatus of claim 9, wherein the catheter includes a guide wire lumen, and the guide wire lumen is engageable with a guide wire for pushing the catheter over the guide wire.