An integrated PET-SPECT imager for small animals

We have built the YAP-PET tomograph: an integrated PET-SPECT imager for per forming in vivo studies on new radiopharmaceuticals and tumor therapy evalu ation in small animals. The field of view is 4 cm axially and 4 cm in diame ter. The scanner is made of four detector modules that can rotate up to 360 degrees. Each detector is composed of a YAP:Ce matrix (20 x 20 match like crystals of dimensions 2 x 2 x 30 mm(3)) coupled to a position-sensitive ph otomultiplier (Hamamatsu R2486-06). Two opposite detectors are equipped wit h high-resolution lead collimators (0.6 mm hexagonal holes, 0.15 mm septa t hickness, and 20 mm thick). The collimators are easily mountable and remova ble from the detector heads, so as to obtain a two-head PET combined with a two-head SPECT, or a four-head PET scanner. (C) 2001 Elsevier Science B.V. All rights reserved.