Contents I. Introduction
Discrete crystal detector modules have traditionally been used to achieve high spatial resolution for small animal positron emission tomography (PET) scanners [1]. However, cost goes up considerably as one uses a smaller and smaller cross-section crystal. We have previously investigated a continuous miniature crystal element (cMiCE) detector that comprised a 25 mm by 25 mm by 4 mm-thick slab of LSO coupled to a 26-mm square, cross-anode position sensitive photomultiplier tube (PMT) (Hamamatsu R5900-00-C12, Japan) as a lower cost alternative to high resolution discrete crystal designs [2]. In that work, we introduced a statistics-based positioning (SBP) algorithm, similar to previously proposed maximum-likelihood (ML) methods [3]–[5], which improved the positioning characteristics near the edge of the crystal. We now investigate the performance characteristics using a 52-mm square, 64-channel flat panel PMT (Hamamatsu H8500, Japan). Experimental results were acquired along one axis of the detectors for a 25 mm by 25 mm by 4 mm-thick slab of LSO (CTI, Knoxville, TN) and a 50 mm by 50 mm by 8 mm-thick slab of LYSO (Saint Gobain, Newbury, OH).
