METHODS AND APPARATUS FOR IN VIVO IDENTIFICATION AND CHARACTERIZATION OF VULNERABLE ATHEROSCLEROTIC PLAQUES

摘要

Methods and apparatus for analyzing the chemical composition of vulnerable plaques with an intravascular catheter having a near-infrared light source, a fiber-optic probe, a mechanism for directing the light from the light source into a blood vessel, and detectors for detecting light reflected or scattered by the tissue. The light source may be a tunable laser, and may transmit an incident beam having a wavelength ranging from 1400 to 4100 nm. A computer may be included to receive and process the spectral data in the analysis of the vulnerable plaques. A catheter system may be configured to provide near-IR spectrometric imaging of arteries to non-destructively locate and determine lipid pool and fibrous cap size and composition. Additionally, mediators and cellular components may be also determined that are typically associated with vulnerable plaques which have an increased risk of rupture. The lipid pool, fibrous cap, and inflammatory response may serve as an in vivo marker for vulnerable atherosclerotic plaques. Methods are further provided for prospectively identifying and characterizing vulnerable plaques which may include the steps of focusing near-IR light onto a blood vessel wall; detecting the scattered light in the region; and analyzing the resulting spectra across the full preselected wavelength range, particularly in the ranges that include identifying peaks for vulnerable plaque constituents.