An algorithm for detecting lesions in CBF and CBV perfusion maps

This paper presents an algorithm that enables detection of lesions in CBF and CBV perfusion maps. There are two steps of the algorithm: at the first step the algorithm detects symmetry axis of an image (between left and right hemisphere), in the second stage the level of asymmetry in cerebral blood flow and cerebral blood volume is measured by detection of regions with different perfusion in both brain hemispheres. Test of the algorithm were performed on a set of 56 different CBF and CBV images showing or not cerebral blood flow and volume anomalies. The paper also describes the method for estimating cerebral blood flow with a non diffusing contrast agent based on the Meier - Zierler convolution model as well as CBF, CBV, MTT and TTP perfusion maps.