The optimal design of non-parallel hole collimators

Collimators determine the imaging properties of the gamma camera in nuclear medicine. Because collimators form images by absorption of radiation, the resolution and sensitivity are related by a geometric trade-off: the number of counts detected is proportional to the square of the FWHM. An optimal collimator design maximizes sensitivity for a fixed FWHM. For parallel holes, the theory of optimal collimator design is well-understood. For example, at a fixed energy, all optimal collimators have the same thickness. A strategy for the optimal design of non-parallel hole collimators is proposed based on the idea that each collimator hole and septa should locally resemble an appropriate optimal parallel-hole design. Based on this strategy, optimal conebeam and fanbeam designs are presented and their performance analyzed