voxelbased analysis of pet amyloid ligand 11cpib uptake in alzheimer disease background pet studies with nmethyl11c24methylaminophenyl6hydroxybenzothiazole 11cpib have revealed an increased tracer uptake in several brain regions in alzheimer disease adobjective to employ voxelbased analysis method to identify brain regions with significant increases in 11cpib uptake in ad vs healthy control subjects indicative of increased amyloid accumulation in these regionsmethods we studied 17 patients with ad and 11 control subjects with pet using 11cpib as tracer parametric images were computed by calculating a regiontocerebellum ratio over 60 to 90 minutes in each voxel group differences in 11cpib uptake were analyzed with statistical parametric mapping spm and automated regionofinterest roi analysisresults spm showed increased uptake p 0001 in the frontal parietal and lateral temporal cortices as well as in the posterior cingulate and the striatum no significant differences in uptake were found in the primary sensory and motor cortices primary visual cortex thalamus and medial temporal lobe these results were supported by automated roi analysis with most prominent increases in ad subjects in the frontal cortex 11cpib uptake 163 of the control mean and posterior cingulate 146 followed by the parietal 146 and temporal 145 cortices and striatum 133 as well as small increases in the occipital cortex 117 and thalamus 115conclusions voxelbased analysis revealed widespread distribution of increased 11cpib uptake in alzheimer disease ad these findings are in accordance with the distribution and phases of amyloid pathology in ad previously documented in postmortem studies