Lossless data compression for short duration 3D frames in positron emission tomography

H₂O¹⁵ 3D bolus studies and other dynamic 3D protocols in positron emission tomography (PET) require frame durations of five seconds or less as the protocol begins, with required frame durations increasing as the study progresses. A goal in PET acquisition is sustained 3D frame duration of ten seconds, with shorter frame durations allowed for a limited time. Transfer of projection arrays to an acquisition hard disk is a major limit of frame duration. Data compression can be used to increase the effective disk throughput and therefore decrease the sustained frame duration. The authors discuss the use of lossless compression hardware in a modern PET 3D acquisition system. The hardware uses an implementation of Lempel-Ziv compression with an estimated sustained throughput of 20 megabytes per second and compression ratios of 3 to 10 for short duration 3D projections arrays. Compression use can decrease the minimum sustainable frame duration to less than 10 seconds for an ECAT EXACT HR