Dennis R. Chapman

Single Photon Emission Computed Body Tomography Using a Multiplane Scanner

This paper addresses a computer interface and required software developed for data acquisition and tomographic reconstruction using a standard nuclear medicine computer (32K Modumed-Medical Data Systems) interfaced to the Anger Multiplane Tomographic Scanner (PhoCon-Searle Radiographics). This combination provides single-photon emission computed body tomography, with longitudinal and transverse section capabilities. During acquisition the computer digitizes and records on magnetic disk the information generated by each scintillation event. Serial mode acquisition is utilized to create a list of the coordinates of the scintillation events in the crystal and which probe detected the event. This list contains markers every 10 milliseconds. These markers are pointers to the X coordinate of the probes. The Y coordinate of the probes are stored in a directory at the first disk record. Tomograms are reconstructed by back-projection of each scintillation event along a line passing through the focal point of the collimators. Programs have been developed to reconstruct one or multiple longitudinal or transverse sections. Once the image has been reconstructed, standard image manipulations such as contrast enhancement, color display, and movie display can be performed.