Image-guided renal nerve ablation

• US 9,028,470 B2
• Filed: 06/15/2012
• Issued: 05/12/2015
• Est. Priority Date: 06/17/2011
• Status: Active Grant

• Current Assignee: University of Utah Research Foundation (State of Utah)
• Original Assignee: University of Utah Research Foundation (State of Utah)
• Inventors: Marrouche, Nassir F., Parker, Dennis L.
• Primary Examiner(s): Gedeon, Brian T
• Application Number:
  US13/525,082
• Publication Number:
  US 20130023862A1
• Time in Patent Office: 1,061 Days
• Field of Search: None
• US Class Current: 606/3
• CPC Class Codes: A61B 2018/00404 Blood vessels other than those in or around the heart
• CPC Class Codes: A61B 2018/00434 Neural system
• CPC Class Codes: A61B 2018/00511 Kidney
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/00791 Temperature
• CPC Class Codes: A61B 2090/374 NMR or MRI
• CPC Class Codes: A61N 7/02 Localised ultrasound hyperthermia hyperthermia in general A61F7/00

Abstract

A method of treating hypertension in a mammal is described, including: by focused sound energy, heating at least one nerve at a surface of a renal artery in a mammal; during the heating and by magnetic resonance imaging, repeatedly determining thermal levels in each of first and second volumetric zones of a region that includes at least a portion of the surface, the second zone being adjacent to the first zone; after determining that an indicium of a thermal level in the first zone exceeds a first threshold, and upon determining that an indicium of a thermal level in the second zone exceeds a second threshold, ceasing the heating of the at least one nerve for at least three months; and as a result of the heating, lowering a blood pressure in the mammal.

Claims

1. A method of treating hypertension in a mammal, comprising:

by focused sound energy, heating at least one nerve at a surface of a renal artery in a mammal;

during the heating and by magnetic resonance imaging, repeatedly determining thermal levels in each of a first volumetric zone and a second volumetric zone within a target region that includes at least a portion of the surface and is subject to the heating;

after determining that an indicium of a thermal level in the first zone exceeds a first threshold, and upon determining that an indicium of a thermal level in the second zone exceeds a second threshold, different from the first threshold, ceasing the heating of the at least one nerve for at least one day; and

as a result of the heating, lowering a blood pressure in the mammal.

2. The method of claim 1, wherein the first zone is substantially concentric with the second zone.

3. The method of claim 1, wherein the magnetic resonance imaging comprises a proton resonance frequency acquisition sequence.

4. The method of claim 1, wherein the heating is ceased for at least four months.

5. The method of claim 1, wherein the heating is ceased for at least six months.

6. The method of claim 1, wherein the heating is ceased for at least 12 months.

7. The method of claim 1, wherein the second zone is adjacent to the first zone.

8. A method of treating hypertension in a mammal, comprising:

by focused sound energy, heating a first region of at least one nerve at a surface of a renal artery in a mammal;

during the heating and by magnetic resonance imaging, repeatedly determining thermal levels in each of a first volumetric zone and a second volumetric zone within the first region that includes at least a portion of the surface and is subject to the heating of the first region;

after determining that an indicium of a thermal level in the first zone exceeds a first threshold, and upon determining that an indicium of a thermal level in the second zone exceeds a second threshold, different from the first threshold, heating a second region of the at least one nerve by focused sound energy;

during the heating and by magnetic resonance imaging, repeatedly determining thermal levels in each of a third volumetric zone and a fourth volumetric zone of the second region that includes at least a portion of the surface and is subject to the heating of the second region;

after determining that an indicium of a thermal level in the third zone exceeds a third threshold, and upon determining that an indicium of a thermal level in the fourth zone exceeds a fourth threshold, different from the third threshold, ceasing the heating of the at least one nerve for at least one day; and

as a result of the heating, lowering a blood pressure in the mammal.

9. The method of claim 8, wherein the third zone is substantially concentric with the fourth zone.

10. The method of claim 8, wherein the first region and the second region defines a pathway.

11. The method of claim 8, wherein the heating is ceased for at least four months.

12. The method of claim 8, wherein the heating is ceased for at least six months.

13. The method of claim 8, wherein the heating is ceased for at least 12 months.

14. The method of claim 8, wherein the second zone is adjacent to the first zone and wherein the fourth zone is adjacent to the third zone.

15. A system for performing renal nerve ablation, comprising:

a HIFU device comprising at least one ultrasound transducer and configured to heat a targeted tissue at a focal region of the array;

a MRI device programmed to monitor thermal levels in a plurality of volumetric zones; and

a control system having instructions for;

by the HIFU device, heating the targeted tissue;

during the heating and by the MRI device, repeatedly determining thermal levels in each of a first volumetric zone and a second volumetric zone within a target region that includes the targeted tissue and is subject to the heating;

after determining that an indicium of a thermal level in the first zone exceeds a first threshold, and upon determining that an indicium of a thermal level in the second zone exceeds a second threshold, different from the first threshold, ceasing the heating of the targeted tissue for at least one day.

16. The system of claim 15, wherein the first zone is substantially concentric with the second zone.

17. The system of claim 15, wherein the MRI device comprises at least one RF coil that allows sequences of currents to acquire images.

18. The system of claim 15, wherein the second zone is adjacent to the first zone.