Methods and devices for ablation

• US 8,057,465 B2
• Filed: 04/16/2007
• Issued: 11/15/2011
• Est. Priority Date: 10/22/1996
• Status: Expired due to Fees

• Current Assignee: St. Jude Medical, Atrial Fibrillation Division, Inc. (Abbott Laboratories)
• Original Assignee: St. Jude Medical, Atrial Fibrillation Division, Inc. (Abbott Laboratories)
• Inventors: Richman, Roxanne L., Sliwa, John W. Jr., Champsaur, Gerard, Crowe, John E., Vaska, Matthias, Anderson, Scott C., Podmore, Jonathan L.
• Primary Examiner(s): PEFFLEY, MICHAEL F
• Application Number:
  US11/785,159
• Publication Number:
  US 20070255276A1
• Time in Patent Office: 1,674 Days
• Field of Search: 606/27, 606/28, 606 32- 34, 606/41, 601/2, 601/3, 600/439, 600/459, 600/461, 600/462, 607/101, 607/102
• US Class Current: 606/27
• CPC Class Codes: A61B 17/22012 in direct contact with, or very close to, the obstruction or concrement for removing obstructions in blood vessels by laser A61B18/245
• CPC Class Codes: A61B 17/2202 the ultrasound transducer being inside patient's body at the distal end of the catheter
• CPC Class Codes: A61B 17/2251 characterised by coupling elements between the apparatus, e.g. shock wave apparatus or locating means, and the patient, e.g. details of bags, pressure control of bag on patient
• CPC Class Codes: A61B 18/00 Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body eye surgery A61F9/007; ear surgery A61F11/00
• CPC Class Codes: A61B 18/02 by cooling, e.g. cryogenic techniques devices for cooling specific reflex points of the body within cell-life limits A61H39/06
• 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 18/1402 Probes for open surgery
• CPC Class Codes: A61B 18/148 having a short, rigid shaft for accessing the inner body transcutaneously, e.g. for neurosurgery or arthroscopy
• CPC Class Codes: A61B 18/1482 having a long rigid shaft for accessing the inner body transcutaneously in minimal invasive surgery, e.g. laparoscopy
• 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 18/18 by applying electromagnetic radiation, e.g. microwaves radiation therapy A61N5/00
• CPC Class Codes: A61B 18/20 using laser
• CPC Class Codes: A61B 2017/00243 cardiac
• CPC Class Codes: A61B 2017/00247 Making holes in the wall of the heart, e.g. laser Myocardial revascularization
• CPC Class Codes: A61B 2017/00252 for by-pass connections, i.e. connections from heart chamber to blood vessel or from blood vessel to blood vessel
• CPC Class Codes: A61B 2017/003 Steerable
• CPC Class Codes: A61B 2017/22077 with a part piercing the tissue A61B2017/22044 takes precedence
• CPC Class Codes: A61B 2017/2253 using a coupling gel or liquid
• CPC Class Codes: A61B 2017/3419 Sealing means between cannula and body
• CPC Class Codes: A61B 2018/00005 Cooling or heating of the probe or tissue immediately surrounding the probe
• CPC Class Codes: A61B 2018/00023 : closed, i.e. without wound contact by the fluid
• CPC Class Codes: A61B 2018/0016 : Energy applicators arranged in a two- or three dimensional array
• CPC Class Codes: A61B 2018/00214 : Expandable means emitting energy, e.g. by elements carried thereon
• CPC Class Codes: A61B 2018/00232 : having an irregular shape
• CPC Class Codes: A61B 2018/00261 : arranged in a line
• CPC Class Codes: A61B 2018/00285 : Balloons
• CPC Class Codes: A61B 2018/00291 : using suction
• CPC Class Codes: A61B 2018/00351 : Heart
• CPC Class Codes: A61B 2018/00363 : Epicardium
• CPC Class Codes: A61B 2018/00392 : Transmyocardial revascularisation
• CPC Class Codes: A61B 2018/00577 : Ablation
• CPC Class Codes: A61B 2018/00654 : with individual control of each of a plurality of energy emitting elements
• CPC Class Codes: A61B 2018/00797 : measured by multiple temperature sensors
• CPC Class Codes: A61B 2018/00839 : Bioelectrical parameters, e.g. ECG, EEG
• CPC Class Codes: A61B 2018/00898 : Alarms or notifications created in response to an abnormal condition
• CPC Class Codes: A61B 2018/00982 : combined with or comprising means for visual or photographic inspections inside the body, e.g. endoscopes
• CPC Class Codes: A61B 2018/1213 : creating an arc
• CPC Class Codes: A61B 2018/142 : at least partly surrounding the target, e.g. concave, curved or in the form of a cave
• CPC Class Codes: A61B 2018/1467 : using more than two electrodes on a single probe
• CPC Class Codes: A61B 2018/147 : Electrodes transferring energy by capacitive coupling, i.e. with a dielectricum between electrode and target tissue
• CPC Class Codes: A61B 2018/1472 : for use with liquid electrolyte, e.g. virtual electrodes
• CPC Class Codes: A61B 2090/3614 : using optical fibre
• CPC Class Codes: A61B 2090/3782 : transmitter or receiver in catheter or minimal invasive instrument
• CPC Class Codes: A61B 2090/395 : with marking agent for marking skin or other tissue
• CPC Class Codes: A61B 2218/002 : Irrigation
• CPC Class Codes: A61B 2218/007 : Aspiration
• CPC Class Codes: A61B 34/20 : Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
• CPC Class Codes: A61B 5/287 : Holders for multiple electrodes, e.g. electrode catheters for electrophysiological study [EPS]
• CPC Class Codes: A61N 1/056 : Transvascular endocardial electrode systems
• CPC Class Codes: A61N 1/06 : for high-frequency therapy
• CPC Class Codes: A61N 1/3629 : in combination with non-electric therapy
• CPC Class Codes: A61N 7/02 : Localised ultrasound hyperthermia hyperthermia in general A61F7/00

Abstract

An ablating device has a cover which holds an interface material such as a gel. The cover contains the interface material during initial placement of the device. The ablating device may also have a removable tip or a membrane filled with fluid. In still another aspect, the ablating device may be submerged in liquid during operation.

Claims

1. A system for ablating tissue with ultrasound energy, comprising

a plurality of ultrasound ablating elements, each ablating element being adapted to emit focused ultrasound energy;

and

a control system coupled to the ablating elements, the control system programmed to control activation of the ablating elements and to automatically change a frequency of the ablating elements when ablating the same tissue structure,

wherein the control system is programmed to activate each ablating element at a first frequency for a first time period and to activate each ablating element at a second frequency, which is a predetermined frequency different from the first frequency, for a second time period.

2. The system of claim 1, wherein the control system is adapted to move a focus of the ultrasound energy relative to a tissue structure being ablated.

3. The system of claim 2, wherein the control system is adapted to move the focus closer to a near surface of the tissue structure being ablated.

4. The system of claim 1, wherein the control system includes means for assessing the adequacy of contact between the ablating elements and the tissue structure being ablated.

5. The system of claim 4, wherein the assessing means is carried out by measuring an electrical impedance.

6. The system of claim 1, wherein the control system includes a sensor adapted to assess the adequacy of contact between the ablating elements and a tissue structure being ablated.

7. The system of claim 6, wherein the sensor is adapted to measure an electrical impedance.

8. The system of claim 1, wherein the control system is programmed to activate the plurality of ablating elements in a predetermined sequence.

9. The system of claim 1, wherein the control system is adapted to deliver 90% of the focused ultrasound energy within a focus area defined by a focal length of about 2-20 mm and an angle of about 10 to 170 degrees when viewed along a focal axis.

10. The system of claim 1, wherein at least one of the plurality of ablating elements has a concave ablating surface.

11. The system of claim 1, wherein the focused ultrasound has a focal length of about 2-20 mm.

12. The system of claim 1, wherein the first frequency is less than the second frequency.

13. The system of claim 1, wherein the first frequency is about 2-7 MHz and the second frequency is about 2-14 MHz.

14. The system of claim 1, wherein the first time period is less than the second time period.

15. The system of claim 1, wherein the first time period is less than about one second.

16. The system of claim 1, wherein the control system is programmed to activate each ablating element at the first frequency for a number of discrete time periods.

17. The system of claim 1, wherein the control system is programmed to activate each ablating element at a third frequency, which is different from the first and second frequencies, for a third time period.

18. The system of claim 17, wherein the third frequency is about 6-16 MHz.

19. The system of claim 1, wherein the control system is programmed to measure at least one of a tissue thickness, a fat thickness, a muscle thickness and a blood flow velocity.

20. The system of claim 1, wherein each ablating element further comprises a membrane, and wherein the membrane and the ablating element define a fluid cavity therebetween.

21. The system of claim 20, wherein the membrane is inflatable.

22. The system of claim 20, wherein the membrane is adapted to tilt the ablating element relative to a tissue surface.