Triangular Spect System for 3-D Total Organ Volume Imaging: Performance Results and Dynamic Imaging Capability

The basic concept of Triangular SPECT System for 3-D organ volume imaging was reported last year. Further stringent imaging tests with the initial experimental system revealed that the composite SPECT images from three detectors remove small artifacts present in the individual detector SPECT images by their crosscancellation. Since then we have developed a clinical prototype with dynamic SPECT capability for rapidly changing physiological process. Its system performance results are reported here. The system has fast rotation speed up to 4 revolutions per minute with <1 second reversing time for continuous data collection during clockwise and counter-clockwise rotations. This continuous rotation provides the time-freezing capability of dynamic physiologic process down to every 5 seconds by 2 л data collection for every 120° rotation. Thus SPECT time series images can be generated to every consecutive 5 seconds. Radioisotope distribution in vivo is inherently dynamic in nature such as in Xe-133 breath-in/wash-out studies for regional cerebral blood flow (rCBF) measurement.