Single photon emission computed tomography (SPECT). Principles and instrumentation.

SPECT systems have successfully imaged most major organ systems within the body in conjunction with conventional radiopharmaceuticals. SPECT imaging provides a new three-dimensional perspective with improved lesion detectability resulting from the elimination of overlying and underlying source activity. High-quality, artifact-free images have been obtained from both scanner and camera-based SPECT systems. Novel geometries are currently being investigated to improve system performance. It is anticipated that new developments in instrumentation and radiopharmaceuticals will result in the increased use of SPECT to noninvasively measure important physiologic processes.