PURPOSE: Our goal was to evaluate the influence of spatially heterogeneous background activity on "hot object" quantitation in brain emission CT. METHOD: We studied the effects of spatially heterogeneous background activity on hot object quantitative recovery in simulations of both spheres and realistic brain distributions (utilizing human MRI data). RESULTS: Significant underestimation of object activity concentration was seen for both cortical and subcortical hot objects, with increasing underestimation for increasing hot object/surrounding gray matter contrast. Significant "spill-in" of counts from surrounding activity was present. CONCLUSION: Hot objects are significantly influenced by both "spill-out" and "spill-in." Qualitative and quantitative analyses of such objects must explicitly consider both spill-out and spill-in; this implies a correction scheme that goes beyond simple division of the observed value by a conventional recovery coefficient.
PURPOSE: Our goal was to evaluate the influence of spatially heterogeneous background activity on "hot object" quantitation in brain emission CT. METHOD: We studied the effects of spatially heterogeneous background activity on hot object quantitative recovery in simulations of both spheres and realistic brain distributions (utilizing human MRI data). RESULTS: Significant underestimation of object activity concentration was seen for both cortical and subcortical hot objects, with increasing underestimation for increasing hot object/surrounding gray matter contrast. Significant "spill-in" of counts from surrounding activity was present. CONCLUSION:Hot objects are significantly influenced by both "spill-out" and "spill-in." Qualitative and quantitative analyses of such objects must explicitly consider both spill-out and spill-in; this implies a correction scheme that goes beyond simple division of the observed value by a conventional recovery coefficient.
Authors: Wayne C Drevets; Michael E Thase; Eydie L Moses-Kolko; Julie Price; Ellen Frank; David J Kupfer; Chester Mathis Journal: Nucl Med Biol Date: 2007-10 Impact factor: 2.408
Authors: Dara M Cannon; Jacqueline M Klaver; Summer A Peck; Denise Rallis-Voak; Kristine Erickson; Wayne C Drevets Journal: Neuropsychopharmacology Date: 2008-10-22 Impact factor: 7.853