System and method of characterizing vascular tissue

• US 7,899,224 B2
• Filed: 06/01/2006
• Issued: 03/01/2011
• Est. Priority Date: 08/26/2002
• Status: Active Grant

• Current Assignee: Cleveland Clinic (Caris Life Sciences, LLC)
• Original Assignee: Cleveland Clinic (Caris Life Sciences, LLC)
• Inventors: Nair, Anuja, Vince, D. Geoffrey, Klingensmith, Jon D., Kuban, Barry D.
• Primary Examiner(s): Ahmed; Samir A
• Assistant Examiner(s): RASHIDIAN, MOHAMMAD M
• Application Number:
  US11/445,591
• Publication Number:
  US 20060253033A1
• Time in Patent Office: 1,734 Days
• Field of Search: 382/100, 382128-132, 600/301, 600/437, 600/467, 128/922, 250/455, 356/39, 377/10, 601/2, 606/7
• US Class Current: 382/128
• CPC Class Codes: A61B 5/02007 Evaluating blood vessel condition, e.g. elasticity, compliance
• CPC Class Codes: A61B 5/7257 using Fourier transforms
• CPC Class Codes: A61B 5/726 using Wavelet transforms
• CPC Class Codes: A61B 8/0833 involving detecting or locating foreign bodies or organic structures
• CPC Class Codes: A61B 8/12 in body cavities or body tracts, e.g. by using catheters catheters per se A61M25/00
• CPC Class Codes: G06T 2207/30101 Blood vessel; Artery; Vein; Vascular
• CPC Class Codes: G06T 7/0012 Biomedical image inspection

Abstract

A system and method is provided for using backscattered data and known parameters to characterize vascular tissue. Specifically, in one embodiment of the present invention, an ultrasonic device is used to acquire RF backscattered data (i.e., IVUS data) from a blood vessel. The IVUS data is then transmitted to a computing device and used to create an IVUS image. The blood vessel is then cross-sectioned and used to identify its tissue type and to create a corresponding image (i.e., histology image). A region of interest (ROI), preferably corresponding to the identified tissue type, is then identified on the histology image. The computing device, or more particularly, a characterization application operating thereon, is then adapted to identify a corresponding region on the IVUS image. To accurately match the ROI, however, it may be necessary to warp or morph the histology image to substantially fit the contour of the IVUS image. After the corresponding region is identified, the IVUS data that corresponds to this region is identified. Signal processing is then performed and at least one parameter is identified. The identified parameter and the tissue type (e.g., characterization data) is stored in a database. In another embodiment of the present invention, the characterization application is adapted to receive IVUS data, determine parameters related thereto (either directly or indirectly), and use the parameters stored in the database to identify a tissue type or a characterization thereof.

Claims

1. A vascular-tissue-characterization system, comprising a computing device comprising:

a database adapted to store a first set of parameters corresponding to a plurality of vascular tissue types; and

a characterization application electrically connected to said database and adapted to;

receive an intra-vascular ultrasound (IVUS) signal, said IVUS signal representing backscattered data from vascular tissue;

transform said IVUS signal into the frequency domain;

analyze said transformed signal for a plurality of identifiable parameters; and

use said plurality of identifiable parameters and at least a portion of said first set of parameters to characterize at least a portion of said vascular tissue;

wherein said database is further adapted to store at least two parameters corresponding to said plurality of vascular tissue types, said at least two parameters being selected from a group consisting of maximum power, minimum power, frequency at maximum power, frequency at minimum power, y intercept, slope, mid-band fit, and integrated backscatter.

2. The vascular-tissue-characterization system of claim 1, wherein said characterization application is further adapted to transform said at least a portion of said IVUS signal using a fast Fourier transform (FFT).

3. The vascular-tissue-characterization system of claim 1, wherein said characterization application is further adapted to transform said at least a portion of said IVUS signal using the Welch periodogram.

4. The vascular-tissue-characterization system of claim 1, wherein said characterization application is further adapted to transform said at least a portion of said IVUS signal using autoregressive power spectrum (AR) analysis.

5. The vascular-tissue-characterization system of claim 1, wherein said characterization application is further adapted to use said plurality of identifiable parameters and said at least a portion of said plurality of parameters stored in said database to identify the tissue type of said at least a portion of said vascular tissue, said tissue type being selected from a group consisting of fibrous tissues, fibro-lipidic tissues, calcified necrotic tissues, and calcific tissues.

6. The vascular-tissue-characterization system of claim 5, wherein said computing device further comprises a display for imaging said at least a portion of said vascular tissue in a color corresponding to said tissue type.

7. The vascular-tissue-characterization system of claim 6, wherein said characterization application is further adapted to use said IVUS signal to identify where on said display said at least a portion of said vascular tissue should be imaged.

8. The vascular-tissue-characterization system of claim 1, further comprising an IVUS console electrically connected to said computing device, said IVUS console adapted to:

acquire said IVUS signal from an IVUS catheter; and

provide said IVUS signal to said computing device.

9. The vascular-tissue-characterization system of claim 1, wherein the characterization application is adapted to perform a wavelet transformation on said IVUS signal.

10. The vascular-tissue-characterization system of claim 1, wherein the first algorithm is a morphometric algorithm.

11. The vascular-tissue-characterization system of claim 10, wherein the second algorithm is a thin plate spine algorithm.

12. The vascular-tissue-characterization system of claim 1, wherein the one or more landmarks is selected from a group of landmarks consisting of side branch vessels, plaque deposits, and calcium deposits.

13. A method comprising:

utilizing the vascular-tissue-characterization system of claim 1 to image a patient'"'"'s vascular tissue, wherein the resulting image of the patient'"'"'s vascular tissue distinguishes between different types of tissue present in the patient'"'"'s vascular tissue.

14. The method of claim 13, wherein the different types of tissue present in the patient'"'"'s vascular tissue are distinguished in the resulting image by color.

15. The method of claim 14, wherein utilizing the vascular-tissue-characterization system includes:

providing an IVUS signal representative of the patient'"'"'s vascular tissue to the characterization application;

processing the IVUS signal to identify one or more parameters associated with at least a portion of the patient'"'"'s vascular tissue; and

correlating the at least a portion of the patient'"'"'s vascular tissue with a particular type of tissue by comparing the one or more parameters associated with the at least a portion of the patient'"'"'s vascular tissue with the first set of parameters corresponding to the plurality of vascular tissue types.

16. A system for treating a patient comprising:

an intra-vascular imaging system including a console and an intra-vascular catheter, the intra-vascular imaging system configured to output an intra-vascular image signal representative of a vascular tissue; and

a characterization application in communication with the intra-vascular imaging system, the characterization application configured to;

receive the intra-vascular image signal representative of the vascular tissue output from the intra-vascular imaging system;

create an intra-vascular image based on the received intra-vascular image signal;

receive histology data related to the vascular tissue;

create a histology image based on the received histology data;

correlate a region of interest of the histology image with a corresponding region of interest of the intra-vascular image by utilizing a first algorithm to align one or more landmarks of the histology image with one or more corresponding landmarks of the intra-vascular image and utilizing at least a second algorithm to align remaining portions of the histology and intra-vascular images; and

store data representative of one or more parameters associated with the region of interest of the intra-vascular image,

wherein the characterization application stores data representative of one or more parameters associated with a region of interest for a plurality of intra-vascular images such that the stored data defines a database of tissue characterization parameters for a plurality of tissue types, the database of tissue characterization parameters accessible by the characterization application to facilitate classifying a portion of a patient'"'"'s vascular tissue as one of the plurality of tissue types based on a patient intra-vascular image signal associated with the patient'"'"'s vascular tissue output from the intra-vascular imaging system.

17. The system of claim 16, wherein the first algorithm is a morphometric algorithm and the second algorithm is a thin plate spine algorithm.

18. The system of claim 16, wherein the one or more landmarks is selected from a group of landmarks consisting of side branch vessels, plaque deposits, and calcium deposits.

19. The system of claim 16, wherein the characterization application is further configured to produce an image of the patient'"'"'s vascular tissue based on the patient intra-vascular image signal, wherein the resulting image of the patient'"'"'s vascular tissue distinguishes the different types of tissue present in the patient'"'"'s vascular tissue by color.