Collimator design for improved spatial resolution in SPECT and planar scintigraphy.

Abstract

This paper evaluates the design of a new planar-concave collimator with nonuniform response that better matches the body shape than conventional collimators. The collimator properties are evaluated and assessed by means of both a stimulation program and an experimental test using a prototype planar-concave collimator. The results, for points located 150 mm from the axis of rotation, demonstrate that the ratio of radial and tangential spatial resolution in SPECT with the new collimator decreased by 40%, as compared to SPECT with a standard collimator. In planar scintigraphy, the spatial resolution improved correspondingly from 10.9 mm (FWHM) to 7.8 mm in lateral areas of the body. The new collimator reduces nonisotropic blurring in SPECT in addition to improving spatial resolution in both planar scintigraphy and in SPECT.