1. A method for the automatic detection of kidney regions in a sequence of images from a dynamic image study, comprising: a) identifying in an image from said dynamic study a first region of interest around a first kidney and a second region of interest around a second kidney; b) extracting separate image data from said sequence corresponding to the respective regions of interest; and c) performing principal component analysis on said separate image data separately, wherein said performing principal component analysis includes, for each of said dynamic sequences, linearly combining a preselected number of component images of each region of interest, and wherein said linearly combining further includes calculating coefficients for said principal component analysis as normalization factors between counts in the first few component images.