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

Patent metadata

Field	Value
Publication number	US-11166647-B2
Application number	US-201615064265-A
Country	US
Kind code	B2
Filing date	Mar 8, 2016
Priority date	Nov 9, 2007
Publication date	Nov 9, 2021
Grant date	Nov 9, 2021

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.

First claim

What is claimed is:

1. A method for using a laser catheter, the method comprising:
inserting the laser catheter within a cavity, wherein the laser catheter includes a fiber optic core, a distal tip and a pressure sensor disposed near the distal tip, wherein the fiber optic core channels laser light from a laser to the distal tip, wherein the pressure sensor comprises a plurality of segments disposed along the laser catheter at a common radial distance from the fiber optic core but at different radial positions around the fiber optic core, wherein the segments are formed of an electrically conductive material, wherein each of the segments is circumferentially separated from the other segments by a separator that is a separate member inserted between the electrically-conductive segments around a diameter of an outer surface of the laser catheter to thereby electrically and acoustically isolate the segments from each other, and wherein each segment of the segments is configured to independently sense pressure applied to that segment;
pulsing a laser coupled with the laser catheter using a first set of laser parameters; and
separately measuring the frequency response of the material within the cavity in response to the laser pulsing using each of the plurality of segments of the pressure sensor to thereby determine pressures applied at each of the different radial positions around the fiber optic core while the pressure sensor is disposed within the cavity.

2. The method according to claim 1 , further comprising determining the size of the cavity using the measured frequency response.

3. The method according to claim 1 , further comprising identifying the tissue within the cavity based on at least the measured frequency response.

4. The method according to claim 1 , wherein the pressure sensor comprises an outer electrode and inner electrode and a strain sensitive layer disposed between the outer electrode an inner electrode.

5. The method according to claim 1 , wherein measuring the frequency response of the material within the cavity comprises measuring the frequency response using the plurality of segments.

6. The method according to claim 1 , wherein the pressures applied at each of the different radial positions around the fiber optic core are measured in the radial direction normal to the fiber optic core.

7. The method according to claim 6 , wherein the pressures applied at each of the different radial positions around the fiber optic core are measured in the longitudinal direction parallel to the fiber optic core.

8. The method according to claim 1 , wherein the pressure sensor comprises at least two segments and one separator.

9. The method according to claim 8 , wherein the frequency response is measured using pressure readings from each of the at least two segments.

10. The method according to claim 1 , wherein the pressure sensor comprises at least three segments and two separators.

11. The method according to claim 10 , wherein the frequency response is measured using pressure readings from each of the at least three segments.

12. A method for using a laser catheter, the method comprising:
inserting the laser catheter within a cavity, wherein the laser catheter includes a fiber optic core, a distal tip and a pressure sensor disposed at the distal tip, wherein the fiber optic core channels laser light from a laser to the distal tip, wherein the pressure sensor comprises a plurality of segments disposed at the distal tip, wherein each of the segments is located at a different radial position around the fiber optic core and wherein the segments are circumferentially separated from each other by at least one separator disposed at the distal tip and around a diameter of an outer surface of the laser catheter, wherein the segments are formed of an electrically conductive material and the at least one separator is a separate member inserted between the electrically-conductive segments to thereby electrically and acoustically isolate the segments from each other, and wherein each segment of the segments is configured to independently sense pressure applied to that segment;
pulsing a laser coupled with the laser catheter using a first set of laser parameters; and
measuring the frequency response of the material within the cavity in response to the laser pulsing using each of the plurality of segments of the pressure sensor to thereby determine pressures applied at each of the different radial positions around the fiber optic core while the pressure sensor is disposed within the cavity.

13. The method according to claim 12 , wherein the pressure sensor comprises at least three segments and two separators.

14. The method according to claim 12 wherein the pressures applied at each of the different radial positions around the fiber optic core are measured in the radial direction normal to the fiber optic core.

15. The method according to claim 12 wherein the pressures applied at each of the different radial positions around the fiber optic core are measured in the longitudinal direction parallel to the fiber optic core.

Assignees

• Spectranetics Corp

Inventors

• Splinter Robert

Classifications

• A61B18/245 Primary

  for removing obstructions in blood vessels or calculi · CPC title

• A61B5/4836

  Diagnosis combined with treatment in closed-loop systems or methods (A61B5/0036 takes precedence) · CPC title

• A61B18/24

  with a catheter (A61B18/26, A61B18/28 take precedence) · CPC title

• A61B2018/00642

  with feedback, i.e. closed loop control · CPC title

• A61B5/0084

  for introduction into the body, e.g. by catheters (A61B5/1459 takes precedence) · CPC title