A three-dimensional quantification of calcified and non-calcified plaque based on computed tomography coronary angiography images: Comparison with virtual histology intravascular ultrasound

Abstract

The identification, quantification and characterization of coronary atherosclerotic plaque has a major influence on diagnosis and treatment of coronary artery disease (CAD). Recent studies have reported the ability of Computed Tomography Coronary Angiography (CTCA) to identify non-invasively coronary plaque features. In this study, we present a novel methodology for the identification of the plaque burden of the coronary artery and the volumetric quantification of calcified plaques (CP) and non-calcified plaques (NCP), utilizing CTCA images in comparison with virtual histology intravascular ultrasound (VH-IVUS). The proposed methodology includes seven steps: CTCA images pre-processing, blooming effect removal, vessel centerline extraction using Multistencil Fast Marching Method (MSFM), estimation of membership sigmoidal distribution functions, implementation of an extension of active contour models using prior shapes for the lumen, the outer wall and CP segmentation, detection and quantification of NCP and finally three-dimensional (3D) models construction. Bland Altman and correlation plot analyses were performed to assess the agreement between the presented methodology and VH-IVUS. Assessment of volume and length of lesion length in 18 lesions indicated good correlation with VH-IVUS. More specifically, the Pearson’s correlation (r) is (r = 0.93, p < 0.001) and (r = 0.92, p < 0.001) for CP and NCP volume, respectively, while the correlation for the length of lesion is (r = 0.84, p < 0.001) and (r = 0.95, p < 0.001) for CP and NCP, respectively.