title: Quantitative assessment of field uniformity for gamma cameras.
abstract: Objective criteria for judging the uniformity of field floods are developed and the effects of the energy window and scatter material on uniformity are examined. There is a highly significant correlation (p = 0.99) between a 14% difference in average count among adjacent photomultiplier tube regions and observer detection of detuned areas. Similarly, a 10% average count difference is not significantly recognized as a nonuniform area. Results indicate that there is a complex interaction between uniformity, energy window (15-30% symmetrical) and 0-7.6 cm of tissue-equivalent scatter medium interposed between the flood source and the collimator. Quantitation of the flood should be performed to indicate which regions need retuning.
mesh_terms: D011877:Radionuclide Imaging / Q000295:instrumentation* / Q000379:methods