Tissue ablation and cautery with optical energy carried in fluid stream
Methods and systems for modifying tissue use a pressurized fluid stream carrying coherent light energy. The methods and systems may be used for resecting and debulking soft and hard biological tissues. The coherent light is focused within a stream of fluid to deliver energy to the tissue to be treated.
1. A method for modifying tissue, said method comprising:
generating a continuous stream of a light transmissive liquid medium by passing the liquid medium through a nozzle of a probe;
focusing a source of coherent light into the nozzle and to a point within the continuous stream so that said coherent light is transmitted through said stream by total internal reflection; and
directing the stream to tissue.
2. A method as in claim 1 , wherein the stream is generated by passing the liquid medium under pressure through the nozzle with a diameter in the range from 0.01 mm to 1 mm.
3. A method as in claim 2 , wherein the pressure is in the range from 1 psi to 1000 psi.
4. A method as in claim 3 , wherein the coherent light has a power level in the range from 10 mW to 40 W.
5. A method as in claim 1 , wherein the tissue is luminar tissue and the stream is directed radially outward from the probe.
6. A method as in claim 1 , further comprising directing the stream of the light transmissive liquid medium radially outwardly from the probe, and focusing the coherent light within the stream of light transmissive liquid medium as the stream is directed at the tissue.
7. A method as in claim 6 , wherein the stream is generated by passing the liquid medium under pressure through the nozzle and wherein the nozzle has a diameter in the range from 0.01 to 1 mm, the pressure is in the range from 1 psi to 1000 psi, and the coherent light has a power from 10 mW to 40 W.
8. A method as in claim 1 , wherein the tissue is soft tissue and the stream is directed at a line to cut the tissue.
9. A method as in claim 8 , wherein the nozzle has a diameter in the range from 0.01 to 1 mm, the stream is generated by passing the liquid medium through the nozzle at a pressure in the range from 1 psi to 1000 psi, and the coherent light has a power from 10 mW to 40 W.
10. A method as in claim 1 , wherein the tissue comprises a tooth or bone and the stream is directed to drill into the tooth or cut through bone and cartilage.
11. A method as in claim 10 , wherein the nozzle has a diameter in the range from 0.01 to 1 mm, a pressure in the range from 1 psi to 1000 psi, and the coherent light has a power from 10 mW to 40 W.
12. A system for delivering laser energy to tissue, said system comprising:
a probe;
a nozzle for emitting a continuous stream of a light transmissive fluid; and
a waveguide for transmitting coherent light;
and
wherein the waveguide and nozzle are arranged so that coherent light from the waveguide passes through the nozzle and is focused to a point within the continuous stream of light transmissive fluid and transmitted through the continuous stream of light transmissive fluid by total internal reflection.
13. A system as in claim 12 , further comprising a pump for delivering the light transmissive fluid to the nozzle at a pressure from 1 psi to 1000 psi.
14. A system as in claim 13 , wherein the nozzle has a diameter in the range from 0.01 mm to 1 mm.
15. A system as in claim 12 , further comprising a laser source for delivering coherent light to the waveguide at a power level in the range from 10 mW to 40 W.
16. A system as in claim 12 , wherein the probe is adapted to be advanced through luminal surfaces or lumens of a patient body.
17. A system as in claim 12 , wherein the probe has at least one central axial passage for delivering the light transmissive fluid to the nozzle.
18. A system as in claim 17 , wherein the probe comprises an outer tube having an axial lumen and an inner fluid delivery tube reciprocally mounted in the axial lumen, wherein the central axial passage is disposed in the inner fluid delivery tube and the waveguide is disposed in the central axial passage.
19. A system as in claim 18 , wherein the nozzle is disposed to emit the stream of light transmissive fluid laterally through a window in the outer tube.
20. A system as in claim 16 , wherein the nozzle emits the stream of light transmissive fluid at a pressure in the range from 1 psi to 1000 psi and at a stream diameter from 0.01 mm to 1 mm and wherein the coherent light is transmitted at a power level in the range from 10 mW to 40 W.
21. A system as in claim 12 , wherein the probe is hand held and adapted to deliver energy to cut soft tissue.
22. A system as in claim 21 , wherein the probe comprises a shaft having an axis.
23. A system as in claim 22 , wherein the nozzle is oriented to deliver the stream in an axial direction relative to the shaft.
24. A system as in claim 22 , wherein the nozzle is oriented to deliver the stream in a lateral direction relative to the shaft.
25. A system as in claim 21 , wherein the nozzle emits the stream of light transmissive fluid at a pressure in the range from 1 psi to 1000 psi and at a stream diameter from 0.01 mm to 1 mm and wherein the coherent light is transmitted at a power level in the range from 10 mW to 40 W.
26. A system as in claim 12 , wherein the probe is hand held and adapted to deliver energy to drill teeth or cut through bone and cartilage.
27. A system as in claim 26 , wherein the probe comprises a shaft having an axis.
28. A system as in claim 27 , wherein the nozzle is oriented to deliver the stream in a lateral direction relative to the shaft.
29. A system as in claim 26 , wherein the nozzle emits the stream of light transmissive fluid at a pressure in the range from 1 psi to 1000 psi and at a stream diameter from 0.01 mm to 1 mm and wherein the coherent light is transmitted at a power level in the range from 10 mW to 40 W.
30. A system as in claim 12 , further comprising an anchor adapted to engage a tissue surface when the probe is introduced into a body lumen.