Physical performance of the Siemens E.CAM gamma camera.

We evaluated the physical performance of the new Siemens E.CAM gamma camera. The camera is a dual-headed, large detector system with an open gantry dedicated to planar and to multislice single photon emission tomographic (SPET) imaging of the whole body. The energy-independent digital detectors with high-quality photo-multiplier tubes seem to keep the physical performance of the E.CAM camera very stable. The imaging resolution is very good. The SPET resolution is 9.1 mm full-width at half maximum in scatter for high-resolution collimators with a rotational radius of 15 cm. Both planar (< or = 2%) and SPET uniformity (< or = 4%) are excellent. The detectors can be configured at variable angles which allows flexibility, especially in heart studies. Autocontouring performs whole-body and SPET scans as close to the patient as possible. The patient couch, with its very low gamma-ray attenuation, is firm and can be lowered to make patient loading easier. Camera tuning, calibration, acquisition and processing are controlled by two Power Macintosh 8500 computers. The ICON software is easy to use (a mouse-driven system). However, acquisition interrupts and autocontouring errors were noted during our initial experience. The image quality of routine bone and heart scans was excellent. The E.CAM system allows fast and accurate planar and SPET imaging both in clinical practice and research.