Multi-branched cerebrovascular segmentation based on phase-field and likelihood model

Abstract

Angiograms have been extensively used by neurosurgeons for vascular and non-vascular pathology. Indeed, examining the cerebral vessel network is helpful in revealing arteriosclerosis, diabetes, hypertension, cerebrovascular diseases and strokes. Thus, accurate segmentation of blood vessels in the brain is of major importance to radiologists. Many algorithms have been proposed for blood vessel segmentation. Although they work well for segmenting major parts of vessels, these techniques cannot handle challenging problems including (a) segmentation of thinner blood vessels due to low contrast around thin blood vessels; (b) inhomogeneous intensities, which lead to inaccurate segmentation. In order to tackle these challenges, we developed a new Allen Cahn (AC) equation and likelihood model to segment blood vessels in angiograms. Its level set formulation combines length, region-based and regularization terms. The length term is represented by the AC equation with a double well potential. The region-based term combines both local and global statistical information, where the local part deals with the intensity inhomogeneity, and the global part solves the low contrast problem. Finally, the regularization term ensures the stability of contour evolution. Experimental results show that the proposed method is both efficient and robust, and is able to segment inhomogeneous images with an arbitrary initial contour. It outperforms other methods in detecting finer detail.