Determining detector requirements for medical imaging applications

The Cramér–Rao lower bound on estimator variance is used as a tool for assessing radiation detector requirements for nuclear medicine imaging. The classical bound for unbiased estimators is reviewed and its relationship to the well-known propagation-of-error formula is demonstrated. The uniform Cramér–Rao bound is described for situations where unbiased estimation is impractical such as in tomographic imaging. The bounds are used to evaluate the necessary detector requirements for a CsI(Tl)/Si photodiode scintillation camera, and to compare the performance of a Compton-scatter camera to that of a parallel-hole collimator/Anger camera system.