VESSEL ENHANCEMENT FILTERING IN 3-DIMENSIONAL MR ANGIOGRAMS USING LONG-RANGE SIGNAL CORRELATION

Small vessels in three-dimensional BIR angiograms have low visibility in maximum-intensity projection images because of their low contrast. In a previous study, we had two nonlinear filters that appeared to giv e significant improvement in small vessel detail. In this paper, we re port on a generalization of this filter that allows a more general mod eling of the vessels and a more complete suppression of background, On e implementation of the general filter gave a vessel mean contrast-to- noise ratio that is 2.52 and 3.51 times higher than the vessel mean co ntrast-to-noise ratio obtained using our previously reported maximum-m inimum (max-min) filter and cross- section filter, respectively.