METHOD AND APPARATUS FOR RAPID AND SELECTIVE TRANSURETHRAL TISSUE ABLATION

• US 20170065343A1
• Filed: 11/17/2016
• Published: 03/09/2017
• Est. Priority Date: 06/12/2014
• Status: Active Grant

• Current Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Original Assignee: Lowa Approach Inc.
• Inventors: MICKELSEN, Steven R.
• Granted Patent: US 10,433,906 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 18/1206 Generators therefor
• CPC Class Codes: A61B 18/1492 having a flexible, catheter-like structure, e.g. for heart ablation A61B18/1477 takes precedence
• CPC Class Codes: A61B 2018/00029 open
• CPC Class Codes: A61B 2018/00547 Prostate
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/00613 Irreversible electroporation
• CPC Class Codes: A61B 2018/00642 with feedback, i.e. closed loop control
• CPC Class Codes: A61B 2018/00702 Power or energy
• CPC Class Codes: A61B 2018/00714 Temperature
• CPC Class Codes: A61B 2018/0072 Current
• CPC Class Codes: A61B 2018/00732 Frequency
• CPC Class Codes: A61B 2018/00761 Duration
• CPC Class Codes: A61B 2018/00767 Voltage
• CPC Class Codes: A61B 2018/00791 Temperature
• CPC Class Codes: A61B 2018/00988 Means for storing information, e.g. calibration constants, or for preventing excessive use, e.g. usage, service life counter
• CPC Class Codes: A61B 2018/00994 combining two or more different kinds of non-mechanical energy or combining one or more non-mechanical energies with ultrasound
• CPC Class Codes: A61B 2218/002 Irrigation

Abstract

Catheter systems, tools and methods are disclosed for the selective and rapid application of DC voltage pulses to drive irreversible electroporation for minimally invasive transurethral prostate ablation. In one embodiment, a switch unit is used to modulate and apply voltage pulses from a cardiac defibrillator, while in another, the system controller can be configured to apply voltages to an independently selected multiplicity or subsets of electrodes. Devices are disclosed for more effective DC voltage application including the infusion of cooled fluid to elevate the irreversible electroporation threshold of urethral wall tissue and to selectively ablate regions of prostate tissue alone.

Claims

1. An apparatus, comprising:

an electrode controller configured to be operably coupled to a voltage pulse generator configured to produce a pulsed voltage waveform and a catheter including a plurality of electrodes, the electrode controller implemented in at least one of a memory or a processor, the electrode controller including a feedback module, a thermal control module and a pulse delivery module, the feedback module configured to determine a temperature of a target tissue, the thermal control module configured to produce a signal to control a cooling fluid to the catheter based on the temperature of the target tissue, the pulse delivery module configured to deliver an output signal associated with the pulsed voltage waveform to the plurality of electrodes, the pulse delivery module further configured to shunt an excess current associated with the pulsed voltage waveform.

2. The apparatus of claim 1, wherein the voltage pulse generator unit is a cardiac defibrillator.

3. The apparatus of claim 1, wherein the pulse delivery module is configured to select at least a first electrode from the plurality of electrodes and a second electrode from the plurality of electrodes and deliver the output signal associated with the pulsed voltage waveform to the first electrode and the second electrode.

4. The apparatus of claim 1, wherein the pulse delivery module is configured to modulate a characteristic of the output signal, the characteristic including at least one of an amplitude of the output signal, a period of the output signal, or duration of the output signal.

5. The apparatus of claim 1, wherein the pulse delivery module is configured produce the output signal by incorporating intervals with zero voltage into voltage pulses from the voltage pulse generator.

6. The apparatus of claim 1, wherein the electrode controller is configured to interface with an external device to program at least one of an amplitude of the output signal, a period of the output signal, or a duration of the output signal.

7. The apparatus of claim 1, further comprising:

the catheter, a proximal end of the catheter including a handle, at least a portion of the electrode controller disposed within the handle.

8. The apparatus of claim 1, wherein the thermal control module is configured to produce the signal to control at least one of a flow of the cooling fluid or a temperature of the cooling fluid.

9. The apparatus of claim 1, wherein the thermal control module is configured to produce the signal to produce a pulsed flow of the cooling fluid.

10. The apparatus of claim 1, wherein:

the signal is a first signal;

the target tissue is a portion of a urethra; and

the thermal control module is configured to produce a second signal to control a temperature of a heater, the heater configured to heat a portion of a prostate tissue.

11. An apparatus, comprising:

an electrode controller configured to be operably coupled to a voltage pulse generator, a catheter and a heater, the voltage pulse generator configured to produce a pulsed voltage waveform, the catheter including a plurality of electrodes, the electrode controller implemented in at least one of a memory or a processor, the electrode controller including a thermal control module and a pulse delivery module, the thermal control module configured to produce a first signal to control a cooling fluid to the catheter, the thermal control module configured to produce a second signal to control a temperature of a heater, the pulse delivery module configured to deliver an output signal associated with the pulsed voltage waveform to the plurality of electrodes, the pulse delivery module further configured to shunt an excess current associated with the pulsed voltage waveform.

12. The apparatus of claim 11, wherein:

the catheter is configured to be disposed within a urethra such that the plurality of electrodes can supply voltage to a prostate; and

the heater is included in a trans-rectal probe.

13. The apparatus of claim 11, wherein the heater is an ultrasound heater, the second signal is configured to control a characteristic of ultrasound energy produced by the ultrasound heater.

14. The apparatus of claim 11, wherein the heater is an infrared heater, the second signal is configured to control a characteristic of infrared energy produced by the infrared heater.

15. The apparatus of claim 11, further comprising:

an inflation controller configured to be operably coupled to the catheter, the catheter including an expandable member, the inflation controller implemented in at least one of a memory or a processor, the inflation controller configured to produce an inflation signal to control an inflation fluid to the expandable member.

16. A method, comprising:

receiving, at a feedback module of an electrode controller, a temperature signal associated with a temperature of a urethral wall against which a medical a catheter is disposed, the catheter including a plurality of electrodes;

delivering a control signal to a cooling unit to produce a flow of cooling fluid to the catheter, the control signal based on the temperature signal; and

delivering an output signal associated with a pulsed voltage waveform to the plurality of electrodes.

17. The method of claim 16, wherein the delivering the output signal is performed when a temperature of the urethral wall is maintained below a body temperature.

18. The method of claim 16, wherein the control signal is associated with at least one of a flow of the cooling fluid or a temperature of the cooling fluid.

19. The method of claim 16, wherein the output signal is in a range between about 200 Volts and about 4000 Volts.

20. The method of claim 16, wherein the control signal is a first control signal, the method further comprising:

delivering a second control signal to a heater to heat a portion of a prostate tissue.

21. A non-transitory processor readable medium storing code representing instructions to be executed by a processor, the code comprising code to cause the processor to:

receive a temperature signal associated with a temperature of a urethral wall against which a medical a catheter is disposed, the medical catheter including a plurality of electrodes;

produce a control signal to a cooling unit to produce a flow of cooling fluid to the catheter, the control signal based on the temperature signal; and

deliver an output signal associated with a pulsed voltage waveform to the plurality of electrodes when the target tissue is at the target temperature.

22. A system, comprising:

a pulse generator unit configured to produce a pulsed voltage waveform;

a controller unit connected to the pulse generator unit, the controller unit configured to modulate pulses from the generator unit, the controller unit including shunt circuitry configured to shunt excess current;

the controller unit including a thermal control module;

a flexible medical device including a plurality of electrodes, the flexible medical device defining a plurality of ports through which a cooling fluid can flow, the flexible medical device configured to be connected to the controller unit such that a voltage signal associated with the pulsed voltage waveform can be conveyed to the plurality of electrodes;

a fluid pump configured to produce the cooling flow in response to a cooling signal produced by the thermal control module of the controller unit; and

a trans-rectal probe including a probe head having a heater, the heater configured to heat a portion of a prostate tissue in response to a cooling signal produced by the thermal control module of the controller unit.

23. The system of claim 22, wherein the heater is configured to produce a focused ultrasound energy pulse to heat the portion of the prostate tissue.

24. The system of claim 22, wherein the heater is configured to produce an infrared energy pulse to heat the portion of the prostate tissue.

25. The system of claim 22, wherein the catheter includes an expandable member configured to limit movement of catheter within the urethra.

26. An apparatus, comprising:

a catheter shaft defining a flow passage;

a plurality of electrodes coupled to a distal end portion of the catheter shaft;

a controller coupled to a proximal end portion of the catheter shaft, the controller configured to receive a voltage input from a pulse generator and produce a timed pulsed voltage waveform based on the voltage input to the plurality of electrodes, the controller configured to control a flow of fluid through the flow passage.

27. The apparatus of claim 26, wherein the pulse generator is a cardiac defibrillator.

28. The apparatus of claim 26, wherein the controller is disposable.

29. A method of producing irreversible electroporation, comprising:

positioning a catheter within a urethra such that each of a plurality of electrodes coupled to the catheter is in operable communication with a target tissue;

flowing a coolant flow through the catheter such that a temperature of a urethral wall is maintained at a target temperature;

heating, via a trans-rectal probe, a portion of a prostate tissue; and

applying at least one voltage pulse to the plurality of electrodes to generate an electric field for irreversible electroporation ablation in the region of the target tissue.