Adaptive angular sampling approach for emission tomography

This paper presents an adaptive angular sampling approach developed for SPECT systems that require the rotation of the detection system to obtain an adequate angular sampling. The basic idea of the approach is to assign different imaging times across possible sampling angles, based on the efficiency of the camera(s) at each possible angle for collecting imaging information. In this study, we used the resolution-variance tradeoffs and bias-variance tradeoffs as performance indices for guiding the adaptive angular sampling strategy, and applied a highly efficient computation scheme, based on the non-uniform object-space pixilation methods, for deriving the optimum time distribution in near real-time. This approach allows an optimum efficiency for collecting imaging information and therefore offers an improved image quality.