MEDICAL SYSTEM AND METHOD OF USE

• US 20090149846A1
• Filed: 07/02/2008
• Published: 06/11/2009
• Est. Priority Date: 10/07/2003
• Status: Active Grant

• Current Assignee: Tsunami MedTech, LLC
• Original Assignee: Tsunami MedTech, LLC
• Inventors: Shadduck, John H., Hoey, Michael
• Granted Patent: US 8,579,892 B2
• Time in Patent Office: Days
• US Class Current: 606/27
• CPC Class Codes: A61B 17/42 Gynaecological or obstetrical instruments or methods ligaturing clamps or clips for the umbilical cord A61B17/122; curettage A61B17/320708; dilators A61M29/00
• CPC Class Codes: A61B 18/04 by heating by applying electromagnetic radiation A61B18/18; hyperthermia using electric or magnetic fields, radiation or ultrasound A61N
• CPC Class Codes: A61B 2017/00026 Conductivity or impedance, e.g. of tissue
• CPC Class Codes: A61B 2017/00084 Temperature
• CPC Class Codes: A61B 2017/00504 Tissue welding
• CPC Class Codes: A61B 2017/4216 Operations on uterus, e.g. endometrium
• CPC Class Codes: A61B 2018/00005 Cooling or heating of the probe or tissue immediately surrounding the probe
• CPC Class Codes: A61B 2018/00619 Welding
• CPC Class Codes: A61B 2018/0063 Sealing
• CPC Class Codes: A61B 2018/046 in liquid form
• CPC Class Codes: A61B 2018/048 in gaseous form
• CPC Class Codes: A61B 2090/064 for measuring force, pressure or mechanical tension
• CPC Class Codes: A61M 25/10 Balloon catheters A61M25/0125 takes precedence; embolectomy A61B17/22032; retractors A61B17/02; inflatable balloons for placing stents or stent-grafts A61F2/958 ; stomach balloons for treatment of obesity A61F5/0003; oesophagal tubes A61J15/00

Abstract

An instrument and method for applying thermal energy to targeted tissue. An instrument and method for tissue thermotherapy. In one embodiment, a method includes providing a vapor source comprising a pump configured for providing a flow of liquid media from a liquid media source into a vaporization chamber having a heating mechanism, actuating the pump to provide the liquid into the vaporization chamber, applying energy from the heating mechanism to convert a substantially water liquid media into a minimum water vapor level for causing an intended effect in tissue. For examples such levels can comprise at least 60% water vapor, at least 70% water vapor, at least 80% water vapor or at least 90% water vapor for causing an intended effect in tissue.

Claims

1. A medical system for applying thermal energy to tissue, comprising:

an elongated probe with an axis having an interior flow channel extending to at least one outlet in a probe working end;

a source of vapor media configured to provide a vapor flow through at least a portion of the interior flow channel, wherein the vapor has a minimum temperature; and

at least one sensor in the flow channel for providing a signal of at least one flow parameter selected from the group one of (i) existence of a flow of the vapor media, (ii) quantification of a flow rate of the vapor media, and (iii) quality of the flow of the vapor media.

2. The medical system of claim 1, where the minimum temperature is selected from a group consisting of at least 80°

C., 100°

C. 120°

C., 140°

C. and 160°

C.

3. The medical system of claim 1, wherein the sensor is selected from the group consisting of a temperature sensor, an impedance sensor, a pressure sensor and an optical sensor.

4. The medical system of claim 1, wherein a sensor is disposed in the working end.

5. The medical system of claim 1, wherein a sensor is disposed proximate to the at least one outlet.

6. The medical system of claim 1, wherein first and second sensors are axially spaced apart in the probe.

7. The medical system of claim 6, wherein first and second sensors are spaced apart by at least 0.1 mm, 0.5 mm, 1 mm, 5 mm, 10 mm and 50 mm.

8. The medical system of claim 1, wherein first and second sensors are radially spaced apart in the probe.

9. The medical system of claim 1, wherein the source of vapor media includes a pressurized source of a liquid media and an energy source for phase conversion of the liquid media to a vapor media.

10. The medical system of claim 9, further comprising a controller capable of modulating a vapor parameter in response to a signal of a flow parameter;

the vapor parameter selected from the group of (i) flow rate of pressurized source of liquid media, (ii) inflow pressure of the pressurized source of liquid media, (iii) temperature of the liquid media, (iv) energy applied from the energy source to the liquid media, (v) flow rate of vapor media in the flow channel, (vi) pressure of the vapor media in the flow channel, (vi) temperature of the vapor media, and (vii) quality of vapor media.

11. The medical system of claim 9, wherein the energy source comprises at least one of a resistive heat source, an Rf energy source, a light energy source, a microwave energy source, an ultrasound source and an inductive heat source.

12. The medical system of claim 9, wherein the liquid source and controller are capable of providing a flow rate of the liquid media ranging from 0.001 ml/min to 20 ml/min, 0.010 ml/min to 10 ml/min, 0.050 ml/min to 5 ml/min.

13. The medical system of claim 9, wherein the liquid source and controller are capable of providing an inflow pressure of the liquid media ranging from 1 psi to 1000 psi, 10 psi to 500 psi, and 50 psi to 200 psi.

14. A medical system for applying thermal energy to tissue, comprising:

an elongated probe with an axis having an interior flow channel extending to at least one outlet in a probe working end, wherein a wall of the flow channel includes an insulative portion having a thermal conductivity of less than a maximum thermal conductivity; and

a source of vapor media configured to provide a vapor flow through at least a portion of the interior flow channel, wherein the vapor has a minimum temperature

15. The medical system of claim 14, where the maximum thermal conductivity is selected from a group consisting of 0.05 W/mK, 0.01 W/mK and 0.005 W/mK.

16. The medical system of claim 14, where the minimum temperature is selected from a group consisting of at least 80°

C., 100°

C. 120°

C., 140°

C. and 160°

C.

17. The medical system of claim 14, further including at least one sensor in the flow channel for providing a signal of at least one flow parameter selected from the group one of (i) existence of a flow of the vapor media, (ii) quantification of a flow rate of the vapor media, and (iii) quality of the flow of the vapor media.

18. The medical system of claim 14, where the elongated probe includes an extension member, where the interior flow channel comprises a first interior flow channel located within the extension member and extending to at least one outlet in a distal working end, and wherein the extension member includes an insulative portion having the minimum thermal conductivity.

19. The medical system of claim 18, further comprising a second interior channel in the probe and extension member wherein a distal portion of the first and second flow channels are in fluid communication.

20. The medical system of claim 18, further comprising a valve in the first or second flow channel for selectively providing a flow of vapor (i) through the at least one outlet or (ii) through the second channel.

21. The medical system of claim 18, wherein the valve is remote from the at least one outlet.

22. The medical system of claim 18, wherein the valve is proximate the at least one outlet.

23. The medical system of claim 18, wherein the valve is selected from the group of manually actuated valves and electrically actuated valves.

24. The medical system of claim 18, wherein the at least one outlet includes at least one of a reduced cross-section region, a porous structure, a microchannel structure and a diffuser structure.

25. The medical system of claim 18, wherein the cross-section of flow pathway of the at least one outlet is less than 20% of the second channel, less than 10% of the second channel, and less than 5% of the second channel.

26. The medical system of claim 18, wherein a proximal end of the second channel is coupled to a negative pressure source.

27. The medical system of claim 18, wherein the at least one flow outlet is proximate the working end of a needle, a catheter, a rigid probe or a clamp structure.

28. A medical system for delivering energy to tissue, the system comprising:

an elongated probe with a flow channel extending from a proximal portion of the probe to at least one flow outlet in an expandable working end; and

a source of a vapor flow in communication with the flow channel.

29. The medical system of claim 28, wherein the expandable working end comprises a complaint or non-complaint balloon.

30. The medical system of claim 28, wherein the expandable working end comprises at least one of a knit structure, a braided structure, a woven structure, a mesh structure, and a perforated structure.

31. The medical system of claim 28, wherein the expandable working end comprises a diffuser.

32. The medical system of claim 28, wherein the expandable working end includes a porous balloon wall.

33. The medical system of claim 28, wherein the expandable working end carries at least one electrode.

34. The medical system of claim 28, wherein the working end carries spaced apart opposing polarity electrodes.

35. A method of tissue ablation, comprising:

introducing the working end of a probe into targeted tissue;

causing a controlled flow of a vapor media while maintaining a vapor content to a to a minimum water vapor level from at least one outlet in the working end into the targeted tissue at a flow rate; and

permitting the vapor media to condense thereby releasing the heat of vaporization to apply energy to the targeted tissue to cause tissue ablation.

36. The method of claim 35, where the minimum water vapor level comprises a value selected from the group consisting of 60% water vapor, 70% water vapor, 80% water vapor and 90% water vapor.

37. The method of claim 35, further comprising viewing the targeted tissue through a visualization element.

38. The method of claim 37, where the visualization element is coupled to the probe.

39. The method of claim 35, where the flow rate comprises a range of flow rates selected from the group consisting of 0.001 to 20 ml/min, 0.010 to 10 ml/min, and 0.050 to 5 ml/min.

40. The method of claim 35, wherein the vapor media has an inflow pressure selected from the ranges consisting of 0.5 to 1000 psi, 5 to 500 psi, and 25 to 200 psi.

41. The method of claim 35, wherein the energy is applied over an interval ranging from 0.1 to 600 seconds.

42. The method of claim 35, wherein the targeted tissue comprises tissue selected from the group consisting of interstitial and intraluminal tissue.

43. The method of claim 35, including providing a pressure in the targeted tissue ranging between 0.1 psi and 50 psi.

44. The method of claim 35, including providing a flow of a second media for combining with the vapor media to alter the average mass temperature of the combined vapor media and second media.

45. The method of claim 35, wherein the second media is at least one of CO₂, N₂, O₂ or H₂O.

46. The method of claim 35, including controlling pressure in the tissue by modulating the inflow pressure of the flow media.

47. The method of claim 35, including controlling pressure to distend an organ.

48. The method of claim 35, including expanding at least one expandable member in the tissue to control flow of the flow media in the tissue.

49. The method of claim 35, including applying Rf energy to the tissue from at least one electrode in the working end.

50. The method of claim 35, further comprising generating the flow of vapor by at least one of resistive heating means, radiofrequency (Rf) energy means, microwave energy means, photonic energy means, magnetic induction energy means, compression and decompression means, and ultrasonic energy means.

51-80. -80. (canceled)