Method and apparatus for removing plaque from blood vessels using ultrasonic energy

• US 20030069590A1
• Filed: 10/05/2001
• Published: 04/10/2003
• Est. Priority Date: 10/05/1999
• Status: Active Grant

• Current Assignee: Cybersonics, Inc
• Original Assignee: OmniSonics Medical Technologies, Inc.
• Inventors: Rabiner, Robert A., Hare, Brad A.
• Granted Patent: US 6,660,013 B2
• Time in Patent Office: Days
• US Class Current: 606/128
• CPC Class Codes: A61B 17/00234 for minimally invasive surgery A61B17/0218, A61B17/0469, A61B17/12013, A61B17/1285, A61B17/29, A61B17/320016 take precedence
• 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 2017/00137 Details of operation mode
• CPC Class Codes: A61B 2017/00274 Prostate operation, e.g. prostatectomy, turp, bhp treatment
• CPC Class Codes: A61B 2017/22002 preventing restenosis
• CPC Class Codes: A61B 2017/22007 Cavitation or pseudocavitation, i.e. creation of gas bubbles generating a secondary shock wave when collapsing
• CPC Class Codes: A61B 2017/22008 used or promoted
• CPC Class Codes: A61B 2017/22015 with details of the transmission member
• CPC Class Codes: A61B 2017/22018 segmented along its length
• CPC Class Codes: A61B 2017/22051 with an inflatable part, e.g. balloon, for positioning, blocking, or immobilisation A61B2017/22048, A61B2017/3486 take precedence
• CPC Class Codes: A61B 2017/293 with means preventing relative rotation between the shaft and the actuating rod
• CPC Class Codes: A61B 2017/320073 probe
• CPC Class Codes: A61B 2017/320084 Irrigation sleeves
• CPC Class Codes: A61B 2217/005 with suction drainage system
• CPC Class Codes: A61B 2217/007 with irrigation system

Abstract

A method and apparatus for removing plaque, fatty deposits, and other occlusions from blood vessels using ultrasonic energy. The method and apparatus has particular application in removing plaque from the carotid artery in a non-thermal manner. The apparatus is designed to have as small a cross-sectional profile as possible, therefore allowing the apparatus to be used in a minimally-invasive manner. As a result, the apparatus can be used in both surgical and outpatient treatment with minimal post-operative complications and minimal damage to areas other than the area of treatment. An ultrasonic probe may include aspiration channels on its outer surface. An aspiration sheath may surround the ultrasonic probe, such that the location of an aspiration port may be varied axially relative to the ultrasonic tip.

Claims

1. A method for removing plaque from a blood vessel using ultrasonic energy, comprising the steps of:

inserting an ultrasonic probe into the blood vessel;

extending a portion of the ultrasonic probe to an area adjacent to a plaque on an inner surface of the vessel;

transmitting ultrasonic vibrations to said portion of the probe;

reducing the plaque to a particulate material by producing cavitation in the vicinity of the plaque.

2. A method according to claim 1 wherein:

the ultrasonic vibrations are transmitted in an axial direction along the probe tip and in a direction transverse to the axial direction.

3. The method according to claim 1 further comprising the step of:

irrigating the plaque with a fluid before the transmitting step.

4. The method according to claim 1 further comprising the step of:

aspirating the particulate material after the reducing step.

5. The method according to claim 1 wherein:

the blood vessel is a carotid artery.

6. The method according to claim 1 wherein:

the distal portion of the probe tip directly contacts the plaque.

7. The method according to claim 1:

the transmitting of ultrasonic energy is at a power level sufficient to reduce the plaque to a particulate material having individual particles with a diameter at least as small as 10 microns.

8. The method according to claim 1 further comprising:

monitoring a location of the distal end of the probe tip in the vessel.

9. The method according to claim 8, wherein:

the location of the distal end of the probe tip is monitored using ultrasound.

10. The method according to claim 1 further comprising:

monitoring the amplitude of the probe within the vessel.

11. The method according to claim 1 further comprising:

monitoring the temperature of the probe within the vessel.

12. The method according to claim 1 wherein:

a distal portion of the probe is used to produce cavitation in the vicinity of the plaque.

13. The method according to claim 1 wherein:

a tip of the probe is used to produce cavitation in the vicinity of the plaque.

14. The method according to claim 1 wherein:

the plaque is emulsified.

15. The apparatus according to claim 15 wherein:

the transmitting ultrasonic vibrations step is carried out at about 20 kHz.

16. An ultrasonic apparatus for removing plaque from a blood vessel comprising:

an elongate probe having proximal and distal extremities, the elongate probe being sized so that it can be introduced into a blood vessel and having a length so that when the distal extremity is disposed in the vicinity of a plaque on the inner surface of the vessel the proximal extremity is outside of a body of a treated patient, the elongate probe having a passage extending from the proximal extremity to the distal extremity;

a probe tip disposed in the passage, the probe tip being capable of conducting ultrasonic energy into the plaque on the vessel for cavitating the plaque;

an ultrasonic generator which is capable of delivering ultrasonic energy to the probe tip and into the plaque to debulk the vessel by reduction of the plaque to a particulate material;

a handle coupled to the proximal extremity of the elongate probe member.

17. The apparatus according to claim 16 further comprising:

fenestrations disposed along the length of the probe for use in at least one of irrigation and aspiration.

18. The apparatus according to claim 16 wherein:

the ultrasonic generator is configured to run at about 20 kHz.