Shape-driven segmentation of arterial wall in intravascular ultrasound images

Abstract—Segmentation of arterial wall boundaries from in-travascular images is an important problem for many applica-tions in the study of plaque characteristics, mechanical properties of the arterial wall, its 3-D reconstruction, and its measurements such as lumen size, lumen radius, and wall radius. We present a shape-driven approach to segmentation of the arterial wall from intravascular ultrasound images in the rectangular domain. In a properly built shape space using training data, we constrain the lumen and media-adventitia contours to a smooth, closed geome-try, which increases the segmentation quality without any tradeoff with a regularizer term. In addition to a shape prior, we utilize an intensity prior through a nonparametric probability-density-based image energy, with global image measurements rather than pointwise measurements used in previous methods. Furthermore, a detection step is included to address the challenges introduced to the segmentation process by side branches and calcifications. All these features greatly enhance our segmentation method. The tests of our algorithm on a large dataset demonstrate the effectiveness of our approach. Index Terms—Arterial wall segmentation, calcification detec-tion, intensity prior, intravascular ultrasound (IVUS), lumen seg-mentation, media adventitia segmentation, model-based segmen-tation, side branch detection, shape prior. I