A method for correcting the depth-of-interaction blurring in PET cameras

A method is presented for correcting PET images for the blurring caused by variations in the depth-of-interaction in position-sensitive gamma ray detectors. The method uses an empirically determined, tabulated relationship between depth-of-interaction and most probable pulse-height to estimate the unknown depth from the measured pulse-height for each detected gamma ray. In the case of one fine-cut 50x50x30 mm BGO block detector, the method is shown to improve the detector resolution by 25%, averaged over the 50x50 mm face, measured in the geometry corresponding to detection at the edge of the field-of-view. Strengths and weaknesses of the method are discussed and its potential usefulness for improving the images of future PET cameras is assessed.