Central region sensitivity enhancement in SPECT using a combination of parallel and converging collimators

A major problem in SPECT (single photon emission computed tomography) imaging is noise due to the small number of detected photons emitted from a feature of interest. The effects of simultaneously using both parallel and converging collimation to enhance the sensitivity in a central field of view, while adequately sampling the entire object, were investigated. The sensitivity effects of several collimator combinations were simulated for several tool count rates, with and without constant uniform attenuation. Results show that, using one parallel collimator and five converging collimators, the central region has a contrast-to-noise ratio equivalent to using twice the counts with only parallel collimation.<
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