System and Method of Characterizing Vascular Tissue

Abstract

A system and method is provided for using backscattered data and known parameters to characterize vascular tissue. IVUS data is 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) is then identified on the histology image. The computing device identifies a corresponding region on 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 is stored in a database. In another embodiment of the present invention, the characterization application is adapted to use the parameters stored in the database to identify a tissue type or a characterization thereof.

1 - 20 . (canceled) 
     
     
         21 . An intravascular imaging system, comprising:
 an intravascular imaging device sized and shaped for introduction into a vessel of a patient;   a processing system configured to receive an intravascular imaging signal from the intravascular imaging device representative of tissue of the vessel of the patient, the processing system configured to:
 transform the intravascular imaging signal from a first domain into a second domain; 
 analyze the transformed signal based on at least two parameters selected from the group of parameters consisting of maximum power, minimum power, frequency at maximum power, frequency at minimum power, y intercept, slope, mid-band fit, and integrated backscatter; and 
 classify the tissue of at least a region of interest of the vessel based on matching the analyzed signal with a tissue characterization database in communication with the processing system. 
   
     
     
         22 . The system of  claim 21 , wherein the intravascular imaging device is an intravascular ultrasound (IVUS) catheter. 
     
     
         23 . The system of  claim 22 , wherein the intravascular imaging signal is an IVUS signal. 
     
     
         24 . The system of  claim 21 , wherein the first domain is a time domain and the second domain is a frequency domain. 
     
     
         25 . The system of  claim 24 , wherein the processing system is configured to analyze the transformed IVUS signal using autoregressive power spectrum (AR) analysis. 
     
     
         26 . The system of  claim 24 , wherein the processing system is configured to analyze the transformed IVUS signal using a fast Fourier transform. 
     
     
         27 . The system of  claim 24 , wherein the processing system is configured to analyze the transformed IVUS signal using a Welch periodogram. 
     
     
         28 . The system of  claim 24 , wherein the processing system transforms the IVUS signal from the first domain into the second domain using a wavelet transformation. 
     
     
         29 . The system of  claim 21 , wherein the processing system classifies the tissue of at least the region of interest of the vessel by identifying a tissue type selected from a group of tissue types consisting of fibrous tissues, fibro-lipidic tissues, calcified necrotic tissues, and calcific tissues. 
     
     
         30 . The system of  claim 21 , wherein the processing system is further configured to output an image of at least a portion of the vessel including the region of interest to a display in communication with the processing system. 
     
     
         31 . The system of  claim 30 , wherein the output image utilizes a plurality of colors to distinguish between different tissue types. 
     
     
         32 . An intravascular imaging system, comprising:
 a processing system configured to receive an intravascular imaging signal from an intravascular imaging device, the intravascular imaging signal representative of a vessel of a patient, the processing system configured to:
 transform the intravascular imaging signal from a first domain into a second domain; 
 analyze the transformed signal based on at least two parameters selected from the group of parameters consisting of maximum power, minimum power, frequency at maximum power, frequency at minimum power, y intercept, slope, mid-band fit, and integrated backscatter; and 
 classify the tissue of at least a region of interest of the vessel based on matching the analyzed signal with a tissue characterization database in communication with the processing system. 
   
     
     
         33 . The system of  claim 32 , wherein the intravascular imaging signal is an IVUS signal. 
     
     
         34 . The system of  claim 32  wherein the first domain is a time domain and the second domain is a frequency domain. 
     
     
         35 . The system of  claim 34 , wherein the processing system is configured to analyze the transformed IVUS signal using autoregressive power spectrum (AR) analysis. 
     
     
         36 . The system of  claim 34 , wherein the processing system is configured to analyze the transformed IVUS signal using a fast Fourier transform. 
     
     
         37 . The system of  claim 34 , wherein the processing system is configured to analyze the transformed IVUS signal using a Welch periodogram. 
     
     
         38 . The system of  claim 32 , wherein the processing system transforms the IVUS signal from the first domain into the second domain using a wavelet transformation. 
     
     
         39 . The system of  claim 32 , wherein the processing system classifies the tissue of at least the region of interest of the vessel by identifying a tissue type selected from a group of tissue types consisting of fibrous tissues, fibro-lipidic tissues, calcified necrotic tissues, and calcific tissues. 
     
     
         40 . The system of  claim 32 , wherein the processing system is further configured to output an image of at least a portion of the vessel including the region of interest to a display in communication with the processing system, the output image utilizing a plurality of colors to distinguish between different tissue types.