High-resolution hand-held gamma camera

A high resolution, hand-held scintillation camera has been designed and built for specific Nuclear Medicine applications. Primary intended applications are pre-surgical and intra-operative lymphoscintigraphy. The detector head is highly compact with a 1-inch by 1-inch physical field of view. A variety of easily interchangeable collimators including parallel hole, diverging hole, and pinhole allow several choices of imaging parameters including variable spatial resolution, sensitivity and held of view. The camera can be operated in imaging mode or as a probe in a non-imaging mode (simple counting mode). Surgeons performing sentinel node surgeries have the option of using the device as a standard audio-guided counting probe or as an imaging device to improve surgical management. The 20 mm FOV camera has 1 mm intrinsic spatial resolution. System FWHM in air is 2.1 mm and 2.6 mm at 0 cm and 1 cm from a high-resolution parallel hole collimator, respectively. FWHM of 3.8mm is measured 2 cm from a 3 mm pinhole. Pinhole sensitivity is 600 cps/MBq above a 125 cps/MBq background for a 1 cm lesion 1cm below a water surface. Nodes are identified in images even when overall count rate is not above the background from a nearby injection site.