Intra-vascular device with pressure detection capabilities using pressure sensitive material

• US 9,289,173 B2
• Filed: 05/18/2015
• Issued: 03/22/2016
• Est. Priority Date: 11/09/2007
• Status: Active Grant

• Current Assignee: Spectranetics Corporation (Koninklijke Philips N.V.)
• Original Assignee: Spectranetics Corporation (Koninklijke Philips N.V.)
• Inventors: Splinter, Robert
• Primary Examiner(s): Thomson, William
• Assistant Examiner(s): LIPITZ, JEFFREY BRIAN
• Application Number:
  US14/714,925
• Publication Number:
  US 20150245796A1
• Time in Patent Office: 309 Days
• Field of Search: 607 88- 92, 606 2- 12
• US Class Current: 1/1
• CPC Class Codes: A61B 18/24 with a catheter A61B18/26, A61B18/28 take precedence
• CPC Class Codes: A61B 18/245 for removing obstructions in blood vessels or calculi
• CPC Class Codes: A61B 2018/00642 with feedback, i.e. closed loop control
• CPC Class Codes: A61B 2018/00732 Frequency
• CPC Class Codes: A61B 2018/00904 Automatic detection of target tissue
• CPC Class Codes: A61B 2090/065 for measuring contact or contact pressure
• CPC Class Codes: A61B 2090/0813 Accessories designed for easy sterilising, i.e. re-usable
• CPC Class Codes: A61B 2562/0247 Pressure sensors
• CPC Class Codes: A61B 5/0084 for introduction into the body, e.g. by catheters A61B5/1459 takes precedence
• CPC Class Codes: A61B 5/1076 for measuring dimensions inside body cavities, e.g. using catheters A61B3/1005 takes precedence
• CPC Class Codes: A61B 5/1079 using optical or photographic means
• CPC Class Codes: A61B 5/4836 Diagnosis combined with treatment in closed-loop systems or methods A61B5/0036 takes precedence

Abstract

A laser catheter with a pressure sensor is provided according to embodiments of the invention. The pressure sensor may be coupled with the distal end of the laser catheter and may comprise any of various piezoelectric materials, for example Polyvinylidene Difluoride (PVDF). In various embodiments of the invention the pressure sensor is configured to detect pressure longitudinally and coaxially. The pressure sensor may provide an electric potential that is proportional to the vessel pressure and may be used to monitor and/or adjust laser parameters. In other embodiments the results from the pressure sensor may be used to determine the vessel size and/or the type of material being ablated.

Claims

1. A method for performing laser atherectomy, the method comprising:

inserting a laser catheter within a cavity, wherein the laser catheter includes;

a cylindrical outer electrode arranged on an outer surface of the laser catheter;

a cylindrical inner electrode arranged within at least a portion of the cylindrical outer electrode;

a strain sensitive material arranged between the cylindrical outer electrode and the cylindrical inner electrode;

at least three electrical separators arranged in the strain sensitive material configured to spatially separate the cylindrical outer electrode, the cylindrical inner electrode, and the strain sensitive material, wherein the spatially separated cylindrical outer electrode, the cylindrical inner electrode and the strain sensitive material are configured as at least three separate pressure sensors and configured to provide spatial resolution of a pressure distribution;

an inner lining creating an inner lumen, wherein the inner lining is disposed radially inward of the cylindrical inner electrode;

a plurality of optical fibers arranged between the inner lining and the cylindrical inner electrode to channel laser light from a laser to a distal tip of the laser catheter;

pulsing the laser using a first set of laser operating parameters;

measuring the pressure within the cavity using the three separate pressure sensors;

determining whether the detected pressure within the cavity is within tolerances; and

changing the laser operating parameters to a second set of laser operating parameters in response to determining whether the detected pressure within the cavity is within tolerances.

2. The method according to claim 1, wherein the three separate pressure sensors measure at least one of the amplitude and the frequency of the pressure within the cavity.

3. The method according to claim 1, wherein the laser operating parameters include at least one of the repetition rate and the fluence.

4. The method according to claim 1, wherein the second set of laser operating parameters provide laser pulses with less power than the first set of laser operating parameters.