Quantitative evaluation of atherosclerotic plaques using cross-polarization optical coherence tomography, nonlinear, and atomic force microscopy

Abstract

A combination of approaches to the image analysis in cross-polarization optical coherence tomography (CP OCT) and high-resolution imaging by nonlinear microscopy and atomic force microscopy (AFM) at the different stages of atherosclerotic plaque development is studied. This combination allowed us to qualitatively and quantitatively assess the disorganization of collagen in the atherosclerotic arterial tissue (reduction and increase of CP backscatter), at the fiber (change of the geometric distribution of fibers in the second-harmonic generation microscopy images) and fibrillar (violation of packing and different nature of a basket-weave network of fibrils in the AFM images) organization levels. The calculated CP channel-related parameters are shown to have a statistically significant difference between stable and unstable (also called vulnerable) plaques, and hence, CP OCT could be a potentially powerful, minimally invasive method for vulnerable plaques detection.

Polarization Sensitive Optical Coherence Tomography: A Review of Technology and Applications

“…PS-OCT has been performed with as little as one input state and one detected intensity signal. Such settings correspond to regular OCT, however with altered reference polarization for cross-polarization imaging [32,33] or for imaging with variable reference polarization [34]. In contrast, the most comprehensive PS-OCT approaches detected up to 16 elements of the sample's Müller matrix-in every single image pixel [35][36][37][38].…”

Multiphoton tomography in differentiation of morphological and molecular subtypes of breast cancer: A quantitative analysis

“…14 SHG has been used to study a wide spectrum of diseases accompanied by fibrosis, ranging from different kinds of cancer to atherosclerosis, by providing quantitative information about changes occurring in the collagen. [15][16][17][18][19][20][21][22][23] SHG has also been used to study peritumoral breast tissue, in both benign and malignant breast tumors. 6,[24][25][26] The promising prognostic value of quantitative evaluation of intratumoral collagen by SHG imaging, mainly in the luminal breast cancer subtype, has been demonstrated.…”

Multicontrast endomyocardial imaging by single‐channel high‐resolution cross‐polarization optical coherence tomography

“…As one of the polarization sensitive techniques, cross‐polarization (CP) OCT system provides an alternative to access the tissue polarization properties in a simplified fashion. CP‐OCT system uses linearly polarized light to interrogate the sample, usually nonbirefringent, and the loss of polarized backscattering is analyzed by comparing the signal strength from CP and co‐polarization channels . The loss of polarization, or depolarization effect, can be thus used as a contrast to localize the origin of depolarizers presented in tissue.…”

“…It is worth noting that for the original CP‐OCT system proposed by Schmitt and Xiang , the measurements were taken by a single detector in a time‐multiplexed manner, where the reference arm was sequentially switched between the co‐ and cross‐polarization states with respective to that of the sample arm. CP‐OCT systems using similar schemes have been applied in oral tissue characterization , bladder cancer screening , atherosclerotic plaque assessment and biofilm characterization . These systems demonstrated the feasibility of qualitatively characterizing depolarization effect.…”