Laser heated intravascular cautery cap assembly

• US 4,848,339 A
• Filed: 04/11/1988
• Issued: 07/18/1989
• Est. Priority Date: 09/17/1984
• Status: Expired due to Fees

• Current Assignee: Xintec Corporation
• Original Assignee: Xintec Corporation
• Inventors: Rink, Dan, Rink, John, Lee, Garrett
• Primary Examiner(s): Cohen, Lee S.
• Assistant Examiner(s): Shay, David
• Application Number:
  US07/179,678
• Time in Patent Office: 463 Days
• Field of Search: 128/303.1, 128/395, 128/397, 128/398
• US Class Current: 606/7
• CPC Class Codes: A61B 18/14 Probes or electrodes therefor
• CPC Class Codes: A61B 18/22 the beam being directed along or through a flexible conduit, e.g. an optical fibre; Couplings or hand-pieces therefor
• CPC Class Codes: A61B 18/26 for producing a shock wave, e.g. laser lithotripsy
• CPC Class Codes: A61B 18/28 for heating a thermal probe or absorber
• CPC Class Codes: A61B 2017/00084 Temperature
• CPC Class Codes: A61B 2017/00132 Setting operation time of a device A61B2017/00123 takes precedence
• CPC Class Codes: A61B 2017/00154 pulsed
• CPC Class Codes: A61B 2017/00172 Pulse trains, bursts, intermittent continuous operation
• CPC Class Codes: A61B 2017/22038 with a guide wire
• CPC Class Codes: A61B 2017/22069 Immobilising; Stabilising
• CPC Class Codes: A61B 2017/22072 with an instrument channel, e.g. for replacing one instrument by the other
• CPC Class Codes: A61B 2018/00107 Coatings on the energy applicator
• CPC Class Codes: A61B 2018/2272 with reflective or refractive surfaces for deflecting the beam A61B2018/2261, A61B2018/2266 take precedence
• CPC Class Codes: A61B 2090/034 abutting on parts of the device itself
• CPC Class Codes: A61B 2090/062 penetration depth
• CPC Class Codes: A61B 2090/3614 using optical fibre
• CPC Class Codes: B23K 26/0096 Portable laser equipment, e.g. hand-held laser apparatus surgical laser instruments A61B18/20, Dental Lasers A61C1/0046, Hand-held laser dental apparatus for curing resins A61C19/004

Abstract

An improved laser heated intravascular cautery cap construction includes a generally cylindrical outersidewall, and a tappered, annular, distal end wall joining the two sidewalls and defining a closed annular space therebetween. A bore extending axially through the inner sidewall is dimentioned to receive in freely sliding fashion an arterial guidewire or other device such as a doppler flow sensor or an optical bundle for viewing. A unitary or multi-segment annular target element is received within the distal portion of the annular space, and is secured to the outer sidewall adjacent to the end wall with a gap defined between the target element and the inner sidewall. A plurality of holes extend through a connector member parallel to the axis of the sidewalls, each hole receiving therethrough one of a plurality of optical fibers extending through the arterial catheter to a laser light source. Each fiber is aimed at one segment or portion of the target element, so that the fibers may be illuminated selectively to heat the respective portion or segment and the adjacent outer sidewall and distal end wall portions. The air gap defined between the target disc segments and the inner sidewall prevents conduction to the inner sidewall. In a further embodiment, the inner sidewall is lined with a sleeve to further limit heating of the arterial guidewire extending therethrough.

Claims

1. An improved intravascular cautery cap construction, including a closed curved outer sidewall extending symmetrically about an axis, an inner sidewall extending concentrically with said outer sidewall and coaxially therewith, a distal end wall joining like distal ends of said sidewalls to form an annular space therebetween, said inner sidewall having an open bore extending axially therethrough, cap connector means secured to like proximal ends of said sidewalls in sealing fashion to enclose said annular space, means for extending a plurality of optical fibers through said cap connector means into said annular space, said optical fibers including distal ends extending parallel to said axis and directed toward said distal end wall, an annular target disc disposed within said annular space and secured to said outer sidewall in axially spaced relationship to said distal end wall, said target disc disposed to be illuminated by said optical fibers and to be heated thereby.

2. An improved intravascular cautery cap construction, including a closed curved outer sidewall extending symmetrically about an axis, an inner sidewall extending concentrically with said outer sidewall and coaxially therewith, a distal end wall joining like distal ends of said sidewalls to form an annular space therebetween, said inner sidewall having an inner surface defining an open bore extending axially therethrough, cap connector means secured to like proximal ends of said sidewalls in sealing fashion to enclose said annular space, means for extending a plurality of optical fibers through said cap connector means into said annular space, said optical fibers including distal ends extending parallel to said axis and directed toward said distal end wall, and an annular target disc disposed within said annular space and impinging on at least one of said outer sidewall or said distal end wall.

3. The improved intravascular cautery cap construction of claim 2, wherein said target disc comprises a plurality of segments separated by a plurality of radially extending gaps, each of said segments disposed to be illuminated by a respective one of said optical fibers and to be heated thereby.

4. The improved intravascular cautery cap construction of claim 2, wherein said distal end wall extends in tapering, narrowing fashion from the distal end of said outer sidewall to the distal end of said inner sidewall.

5. The improved intravascular cautery cap construction of claim 2, wherein said target disc includes an inner peripheral edge extending about said inner sidewall and spaced radially therefrom to prevent thermal conduction therebetween.

6. The improved intravascular cautery cap construction of claim 2, wherein said target disc is secured to said outer sidewall for direct thermal conduction thereto.

7. The improved intravascular cautery cap construction of claim 2, wherein said target disc is secured to said distal end wall for direct thermal conduction thereto.

8. The improved intravascular cautery cap construction of claim 2, wherein said cap connector means includes a connector member having a continuously curved outer surface, a plurality of channels extending in said outer surface parallel to said axis, each of said channels receiving one of said optical fibers extending therein, and a connector bore extending therethrough and aligned along said axis, said inner sidewall received in said connector bore in close tolerance fit.

9. The improved intravascular cautery cap construction of claim 8, wherein said cap connector means further includes a sleeve member received about said connector member in close tolerance fit and to retain said optical fibers in said channels.

10. The improved intravascular cautery cap construction of claim 9, wherein said sleeve member includes an outer surface configuration received within the proximal end of said outer sidewall in close tolerance fit.

11. The improved intravascular cautery cap construction of claim 2, further including an insulating sleeve disposed concentrically within said bore in said inner sidewall and extending from the proximal end to the distal end of said inner sidewall.

12. The improved intravascular cautery cap construction of claim 11, wherein said insulating sleeve includes a distal portion spaced apart radially from said inner sidewall to define an annular insulating gap between an inner surface of said insulating sleeve and said inner sidewall, said insulating gap being generally disposed in registration with said target disc.

13. The improved intravascular cautery cap construction of claim 12, further including a high reflectivity surface coating secured to the inner surface of said insulating sleeve.

14. The improved intravascular cautery cap construction of claim 2, further including a high reflectivity surface coating secured to the inner surface of said inner sidewall and the inner surface of said outer sidewall.

15. The improved intravascular cautery cap construction of claim 2, further including a central optical fiber extending through said open bore of said inner sidewall, said central optical fiber adapted to be connected to a laser light source and disposed to direct the laser light distally and centrally from said cautery cap bore.

16. The improved intravascular cautery cap construction of claim 2, further including a central optical fiber extending through said open bore of said inner sidewall, said central optical fiber adapted to be connected to a laser light source, a diminutive cautery cap secured to a distal end of said central optical fiber and adapted to be heated selectively by the laser light.

17. An improved intravascular cautery cap construction, including a solid body member formed of a transparent, high temperature material, said body member being substantially cylindrical and including a tapered distal end, a central bore extending axially through said body member and through said tapered distal end, a plurality of holes extending in a proximal end surface of said body member and disposed parallel to an axis thereof, each of said plurality of holes receiving one of a plurality of optical fibers therein, said optical fibers being adapted to be connected to a selectively controlled laser light source and disposed to transmit the laser light into said body member, and first surface coating means secured to outer surface portions of said body member to receive and absorb the laser light illumination and generate thermal energy therefrom.

18. The improved intravascular cautery cap construction of claim 17, wherein said first surface coating means includes a surface coating applied to said tapered distal end of said body member.

19. The improved intravascular cautery cap construction of claim 17, further including second, reflective surface coating means applied to substantially the entire outer surface of said body member to retain the laser light therein.

20. The improved intravascular cautery cap construction of claim 19, wherein said second surface coating means includes a surface coating applied additionally to the surface of the body member defining said central bore to reduce thermal conduction to any device disposed in said central bore.

21. The improved intravascular cautery cap construction of claim 19, further including third surface coating means of hard, reflective material, said third surface coating means extending over at least said second surface coating means to protect said second surface coating means.

22. The improved intravascular cautery cap construction of claim 17, further including a central optical fiber dimensioned to be extended through said open bore of said inner sidewall, said central optical fiber adapted to be connected to a laser light source and disposed to direct the laser light distally and centrally from said cautery cap bore.

23. The improved intravascular cautery cap construction of claim 17, further including a central optical fiber dimensioned to be extended through said open bore, said central optical fiber adapted to be connected to a laser light source, a diminutive cautery cap secured to the distal end of said central optical fiber and adapted to be heated selectively by the laser light.

24. A method for removal of atherosclerotic lesions in arterial vessels, including the steps of advancing an arterial guidewire through an artery to an atherosclerotic lesion, providing a laser heated cautery cap with a bore extending axially therethrough and a plurality of optical fibers connected at the cautery cap in an annular array to deliver laser light energy selectively to the cautery cap, advancing the cautery cap coaxially about and distally along the arterial guidewire to impinge on the atherosclerotic lesion, delivering laser light energy through the optical fibers to the interior of the cautery cap to heat the cautery cap and destroy the atherosclerotic lesion in contact therewith.

25. The method of claim 24, further including providing a plurality of target segments within the cautery cap, each disposed to receive laser light energy from one of said plurality of optical fibers, each target segment being secured to a respective peripheral portion of the cautery cap and disposed to deliver thermal energy thereto in response to illumination by the respective optical fiber.