Experimental evaluation of a modular scintillation camera for SPECT

A modular scintillation camera has been constructed for use in a ring-type single photon tomograph for nuclear medicine. Its performance has been characterized, and experiments with coupling the x and y maximum-likelihood position estimators and varying the sampling of the scintillation light are described. Average spectral resolution in the x direction is equivalent to a 3.6-mm FWHM (full width at half-maximum) Gaussian. In the y direction the response function averages 3.6 mm FWHM. RMS (root mean square) linearity is 0.9 mm in x and 1.1 mm in y. Potential for improving resolution by increasing the sampling density in x has been demonstrated, but a two-dimensional position estimator would be required to maintain acceptable linearity. It is concluded that with the exception of reduced resolution within 6-9 mm of the edge, the camera performance is within design specifications