A study of data loss and mispositioning due to pileup in 2-D detectors in PET

The effect of event pileup was investigated with a PET (positron emission tomography) system which employs a 2-D detector-array system. Event pileup caused losses of resolution of 9%, 19.8%, and 32% of the FWHM (full width at half maximum) for 10, 20, and 30 mCi of positron emitter in the field of view (FOV), respectively. 9.4%, 18.7%, and 28.1% of the data from the outer planes of the module were incorrectly placed in the inner planes for 5, 10, and 15 mCi of the positron emitter in the FOV, respectively. A simple model of the process was formulated and found to be adequate to describe the major features of event pileup for a number of source configurations and a wide range of activities.>