Fiber coupling increases resolution of positron emission tomography
A new positron-emission-tomography (PET) system incorporating arrays of small lutetium oxyorthosilicate (LSO) crystals fiber-coupled to the detectors should offer resolving power nearly an order of magnitude better than conventional systems at a fraction of the cost. Developed by Simon Cherry and coworkers at the University of California, Los Angeles (UCLA), in collaboration with CTI PET Systems Inc. (Knoxville, TN), the microPET system is designed for three-dimensional imaging of small laboratory animals.
At the heart of the system is a ring of 30 detector modules; each consists of an 8 8 array of 2 2 10-mm LSO crystals that are coupled to a 64-element, multichannel photomultiplier tube by 24-cm-long segments of 2-mm-diameter, double-clad multimode optical fiber. The
system will be able to image a volume of 70 70 18 mm with 6-mm3 resolution. The
detectors have already demonstrated an intrinsic resolution of 1.4 mm, an average energy
resolution of 16%, and a temporal resolution of 2.7 ns.