Method and device for the correction of coincidences randoms - in a medical nuclear imaging system

摘要

A method and apparatus for correcting for random coincidences in a gamma camera imaging system are provided, based on the distribution of the object to be imaged as well as the measured singles and coincidence rates. Gamma radiation emitted from the object is detected for multiple projection angles, including detection of a plurality of coincidence events, to generate an object profile. The singles rate and the coincidence rate are also measured for each of the projection angles. A randoms distribution representing random coincidences in the detected coincidence events is then determined, including computing a randoms profile as the convolution of the object profile and a Gaussian function. The determination of the randoms distribution further includes computing a randoms fraction for each of the projection angles based on the measured singles rate and the measured coincidence rate, and then computing the randoms distribution based on the randoms profile and the randoms fraction for each of the projection angles. The coincidence projection data are corrected based on the randoms distribution prior to generating emission images.