CERASPECT: a brain-dedicated SPECT system. Performance evaluation and comparison with the rotating gamma camera

Abstract

Physical parameters and performance of a new brain-dedicated tomograph (CERASPECT) were measured and compared to those of a state-of-the-art single-headed rectangular rotating gamma camera. Spatial resolution, sensitivity, scatter fraction, contrast, uniformity and image quality of the two systems were evaluated using the same radioactive source geometry. The CERASPECT's spatial resolution was 23% higher and its sensitivity was three times greater than those of the gamma camera. The contrast measured with a 15 mm cold lesion was 60% for the CERASPECT and 45% for the gamma camera. Tomographic nonuniformities were measured as the percentage integral and differential uniformity of a cylindrical uniform phantom. At low-statistics counts per slice the integral uniformity was comparable and at high-statistics counts per slice it was equal to 11% and 20% for CERASPECT and the gamma camera, respectively. Image quality is generally superior with the dedicated brain system. The use of new devices with improved physical performance allows more accurate quantitative SPECT functional brain studies.