1. A method of identifying one or more occlusions in vasculature located in a region of interest of image data, comprising: extracting vasculature from the region of interest of image data; identifying a subject geometry of the extracted vasculature; generating a subject graph representative of the vasculature extracted; accessing a predetermined graph; and comparing both the subject graph with the predetermined graph to detect missing or abnormal graph segments and the subject geometry to a predetermined geometry and thereby identify a blockage.