Study on the use of transmission scans for whole body PET attenuation correction

Transmission scans for attenuation correction of whole body PET studies are not acquired routinely, since noise considerations impose acquisition time constraints that make conventional scanning techniques infeasible. The aim of this work is to optimize data acquisition and processing parameters and improve the SNR of whole body transmission scans, in order to achieve within a reasonable time frame, an attenuation correction of the same quality as in cardiac PET. Methods to improve the scanner sensitivity by using additional coincidence planes, as well as smoothing methods for the randoms and the transmission data were investigated. Phantom and patient studies show that transmission scans are feasible for whole body PET studies, with equivalent noise introduced in the chest area as in a typical cardiac PET attenuation correction, at fractions of the time required by conventional transmission scan protocols