WO1998055888A1

WO1998055888A1 - Laser probe

Info

Publication number: WO1998055888A1
Application number: PCT/IL1998/000227
Authority: WO
Inventors: Alex Harel
Original assignee: Optomedic Medical Technologies Ltd.
Priority date: 1997-06-06
Filing date: 1998-05-19
Publication date: 1998-12-10
Also published as: AU7350298A; IL121022A0

Abstract

A laser probe (10) including a slender waveguide (12) for delivery of laser energy from a laser system, and forced air apparatus that provides a flow of forced air through a distal tip of the waveguide (12). In an alternative preferred embodiment, there is provided a laser probe (30) including a slender waveguide (32) for delivery of laser energy from a laser system, and a window substantially transparent to the laser energy sealingly affixed to a distal end of the waveguide (32) so as to substantially prevent ingress of fluids into the waveguide (32).

Description

LASER PROBE

FIELD OF THE INVENTION

The present invention relates generally to laser probes and particularly to a laser probe for use in an aqueous medium that employs positive air pressure to keep the aqueous medium from entering into the probe.

BACKGROUND OF THE INVENTION

Many laser probes are known for directing laser energy into tissues. The following patents are believed to be representative of the art: United States Patents 3,982,541 to L'Esperance, Jr., 4,582,405 to Mϋller et al., 4,688,893 to Laakmann, 4,694,828 to Eichenbaum, 4,782,819 to Adair, 4,825,865 to Zelman, 4,911,712 to Harrington, 4,963,142 to

Loertscher, 5,029,588 to Yock et al., 5,030,217 to Harrington, 5,057,098 to Zelman,

5,074,860 to Gregory et al., 5,122,135 to Dϋrr et al., 5,123,902 to Muller et al., 5,158,560 to

Sogawa et al., 5,178,616 to Uemiya et al., 5,181,916 to Reynolds et al., 5,222,952 to

Loertscher, 5,246,435 to Bille et al., 5,257,988 to L'Esperance, Jr., 5,257,989 to Celaya et al., 5,263,950 to L'Esperance, Jr., and 5,318,560 to Blount et al., and Japanese Patents 5,019,124;

5,092,012; 5,127,026; and 7,059,791.

In particular, United States Patent 4,688,893 to Laakmann describes a narrow diameter, flexible, hollow waveguide that transmits CO₂ laser energy with high efficiency by internal reflection from internally coated surfaces of the waveguide or probe. Japanese Patent 7,059,791 describes a CO laser probe with a multi-joint manipulator and that employs fiber optics for directing the laser energy to different directions as desired. United States Patent 5,030,217 to Harrington describes a flexible CO₂ laser probe with a cladding and core that delivers radiation to a tissue site without obstructing view of the site.

A problem of using such probes for delivery of laser radiation into an aqueous medium, such as in ocular surgery, is that it is difficult to prevent the aqueous medium from entering into the probe.

SUMMARY OF THE INVENTION The present invention seeks to provide an improved laser probe for use in an aqueous medium that employs positive air pressure to keep the aqueous medium from entering into the probe.

The laser probe preferably includes a slender waveguide for delivery of laser energy into an aqueous medium in any desired direction. Forced air is directed into the probe either from an internal air supply of the laser system or by means of an external air connection to the probe. The air flow is preferably adjustable by an air pump. The probe may be open for straight or side firing of the laser energy.

In accordance with an alternative embodiment of the present invention, the probe may be provided with a distal window that seals the probe from ingress therein of fluids and through which the laser energy is transmitted. The beam may be fired straight or the window may have an infrared coating for side firing.

There is thus provided in accordance with a preferred embodiment of the present invention a laser probe including a slender waveguide for delivery of laser energy from a laser system, and forced air apparatus that provides a flow of forced air through a distal tip of the waveguide.

In accordance with a preferred embodiment of the present invention the laser probe also includes a regulator for regulating the flow of forced air. The regulator may include an adjustable air pump. The forced air apparatus may include an air supply of the laser system or an external air connection to the probe. There is also provided in accordance with a preferred embodiment of the present invention a laser probe including a slender waveguide for delivery of laser energy from a laser system, and a window substantially transparent to the laser energy sealingly affixed to a distal end of the waveguide so as to substantially prevent ingress of fluids into the waveguide.

In accordance with a preferred embodiment of the present invention the window has an infrared coating for side firing of the laser energy. For example, for a CO laser system the window includes zinc selenide.

There is also provided in accordance with a preferred embodiment of the present invention a method for delivery of laser energy into an aqueous medium including firing laser energy into the aqueous medium via a distal end of a probe, and forcing air out through the distal end of the probe so as to prevent ingress of the aqueous medium into the probe.

There is also provided in accordance with a preferred embodiment of the present invention a method for delivery of laser energy into an aqueous medium including firing laser energy into the aqueous medium via a distal end of a probe, and sealing the distal end of the probe with a window substantially transparent to the laser energy so as to prevent ingress of the aqueous medium into the probe. BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be understood and appreciated more fully from the following detailed description, taken in conjunction with the drawings in which:

Fig. 1A is a simplified pictorial illustration of a laser probe constructed and operative in accordance with a preferred embodiment of the present invention, wherein air is forced through a distal end of the probe;

Fig. IB is a simplified pictorial illustration of the laser probe of Fig. 1A wherein the distal end of the probe is bent for side firing of laser energy;

Fig. 2 is a simplified pictorial illustration of a laser probe constructed and operative in accordance with another preferred embodiment of the present invention, wherein a window seals a distal end of the probe; and

Fig. 3 is a simplified pictorial illustration of a laser probe constructed and operative in accordance with still another preferred embodiment of the present invention, wherein a window seals a distal end of the probe and the probe is fashioned for side firing of laser energy.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

Reference is now made to Fig. 1 A which illustrates a laser probe 10 constructed and operative in accordance with a preferred embodiment of the present invention. Laser probe

10 preferably includes a slender waveguide 12 extending from a handpiece 14 connected to a laser system 16. Waveguide 12 is preferably rigid, although it may optionally be flexible. Laser system 16 may be any suitable laser system, although the invention is most advantageous for laser systems used for delivery of laser energy into an aqueous medium, such as CO₂.

Forced air apparatus 18 is preferably provided for forcing a flow of air 19 through a distal tip 20 of waveguide 12. Distal tip 20 may be straight as shown in Fig. 1A, or alternatively, may be bent in any desired direction and have a suitable reflective coating, as shown in Fig. IB, for side firing of the laser energy. Forced air apparatus 18 may include a regulator 22, such as an adjustable air pump, for regulating the flow of forced air. In accordance with one preferred embodiment, the source of the air is an air supply 24 of laser system 16. In accordance with another preferred embodiment, the air is supplied from an external source 26.

A pressure sensor 28 may be disposed in distal tip 20 for sensing the pressure of the forced air. Sensor 28 provides feedback to regulator 22 and operates therewith in a closed loop control system to ensure that the flow of forced air is being provided at the optimal pressure and flow for preventing ingress of fluids into waveguide 12.

Reference is now made to Fig. 2 which illustrates a laser probe 30 constructed and operative in accordance with another preferred embodiment of the present invention. Laser probe 30 preferably includes a slender waveguide 32, connectable to laser system 16 of Fig. 1.

A window 34, substantially transparent to the laser energy delivered by laser system 16, is preferably sealingly affixed to a distal end 36 of waveguide 32 so as to substantially prevent ingress of fluids 38 into waveguide 32. For example, for a CO₂ laser system, window 34 preferably comprises zinc selenide. Referring to Fig. 3, it is seen that window 34 may be provided with an infrared coating 40 for side firing of the laser energy.

It will be appreciated by persons skilled in the art that the present invention is not limited by what has been particularly shown and described hereinabove. Rather the scope of the present invention includes both combinations and subcombinations of the features described hereinabove as well as modifications and variations thereof which would occur to a person of skill in the art upon reading the foregoing description and which are not in the prior art.

Claims

C L A I M S

1. A laser probe comprising. a slender waveguide for delivery of laser energy from a laser system; and forced air apparatus that provides a flow of forced air through a distal tip of said waveguide.

2. A laser probe according to claim 1 and comprising a regulator for regulating the flow of forced air.

3. A laser probe according to claim 2 and comprising a pressure sensor disposed in said distal tip for sensing a pressure of the forced air

4. A laser probe according to claim 3 and wherein said pressure sensor provides feedback to said regulator and operates therewith in a closed loop control system

5. A laser probe according to claim 2 and wherein said regulator comprises an adjustable air pump

6. A laser probe according to claim 1 and wherein said forced air apparatus comprises an air supply of the laser system

7. A laser probe according to claim 1 and wherein said forced air apparatus comprises an external air connection to the probe

8. A laser probe according to claim 1 and wherein said waveguide is rigid

9. A laser probe according to claim 1 and wherein said waveguide is flexible

10. A laser probe according to claim 1 and wherein said distal tip is bent for side firing of the laser energy

11. A laser probe comprising a slender waveguide for delivery of laser energy from a laser system, and a window substantially transparent to the laser energy sealingly affixed to a distal end of said waveguide so as to substantially prevent ingress of fluids into said waveguide

12. A laser probe according to claim 1 1 wherein said window has an infrared coating for side firing of the laser energy 13. A laser probe according to claim 11 and wherein said laser system comprises a

CO₂ laser system and said window comprises zinc selenide

14. A laser probe according to claim 12 and wherein said laser system comprises a

CO₂ laser system and said window comprises zinc selenide

15. A method for delivery of laser energy into an aqueous medium comprising firing laser energy into the aqueous medium via a distal end of a probe, and forcing air out through the distal end of said probe so as to prevent ingress of the aqueous medium into said probe

16. A method for delivery of laser energy into an aqueous medium comprising firing laser energy into the aqueous medium via a distal end of a probe, and sealing said distal end of said probe with a window substantially transparent to said laser energy so as to prevent ingress of the aqueous medium into said probe