Application of a small field of view gamma camera based on a 5" PSPMT and crystal scintillator array for high resolution small animal cardiac imaging

We have built a small field-of-view gamma camera based on a 5" diameter Hamamatsu R3292 position sensitive photomultiplier tubes (PSPMT) and Nal(Tl) crystal for high resolution small animal imaging. The instrument was specifically developed for high performance cardiac imaging in rats and mice. Results of measurements in both mouse and rat models will be presented. Dynamic ECG-gated and static planar pinhole pet-fusion images of rat hearts were acquired allowing semi-quantitative and functional interpretation. Additionally, molecular imaging of neutrophil infiltration in a mouse model of myocardial post-ischemic inflammation vi-as performed. We demonstrate the utility of this high resolution instrument for molecular and functional cardiac imaging in small animal models a( heart rates of 250-600 bpm. The superior performance of this new camera will allow the noninvasive monitoring of radiolabeled molecular probes for assessing physiologic processes in the heart as well as other organ systems of small animals.