Patent ID: 7826885

Claim:
An index calculation method executed by an image processing apparatus, comprising: using, at the image processing apparatus, a weight in accordance with a degree of similarity between pixels to filter a plurality of images in order to reduce noise from the plurality of continuous images concerning a specific region of a subject with a contrast medium injected therein, wherein the weight is a first weight for a first degree of similarity and the weight is a second weight greater than the first weight for a second degree of similarity higher than the first degree of similarity; preparing, at the image processing apparatus, first time-density curves concerning arteries in the specific region and second time-density curves concerning tissues in the specific region from the plurality of images with the reduced noise; calculating, at the image processing apparatus, modulation transfer functions indicating local blood flow circulations in the tissues with respect to the respective arteries by curve-fitting so that residual errors of the second time-density curves are minimized with respect to convolution of the modulation transfer functions and first time-density curves; and calculating, at the image processing apparatus, indices concerning the local blood flow circulations with respect to the respective arteries from the modulation transfer functions.