The Design and Manufacture of an Annular Variable-Focusing Collimator for Highsensitivity Brain SPECT

Sensitivity near the center of the brain is critical for some clinical applications of brain SPECT, especially for those applications which require dynamic imaging. We have designed and built a novel collimator for the CeraSPECT dedicated brain SPECT system which uses variable focusing to increase the sensitivity for central regions of its field of view. The sensitivity at the center of the field of view is increased by a factor of two compared to the standard three-segment parallel-hole collimator; this sensitivity gain is achieved without compromising spatial resolution.