Rotating laminar emission camera with GE-detector: experimental results

Experimental results of a prototype rotating laminar emission camera (ROLEC) for nuclear medicine imaging are reported. A 11.5 mm thick, 45 x 45 mm high-purity germanium detector is segmented into 30 1.47 mm wide parallel channels and collimated with 39 mm high parallel plates. Projection data acquired at multiple angular orientations as the detector-collimator assembly is rotated about its center are mathematically reconstructed to image the activity distribution. The spatial resolution of the ROLEC is at least twice as good, at all distances, as that of gamma cameras with high resolution collimators. The better energy resolution of the germanium enhances the detection and resolution of the ROLEC in comparison to gamma cameras with NaI(T1) crystals, the relative superiority increasing with greater volumes and with greater depths. Adequate sensitivity is maintained while achieving these improvements in spatial resolution and in practice; ROLEC images are acquired in less time than pinhole collimator images with gamma cameras.