SPECT image analysis using statistical parametric mapping in patients withParkinson's disease

This study investigated alterations in regional cerebral blood flow (rCBF) in patients with Parkinson's disease using statistical parametric mapping ( SPM). Methods: Noninvasive rCBF measurements using Tc-99m-ethyl cysteinate dimer (ECD) SPECT were performed on 28 patients with Parkinson's disease an d 48 age-matched healthy volunteers. The Parkinson's disease patients were divided into two groups, 16 patients with Hoehn and Yahr stage I or II and 12 patients with Hoehn and Yahr stage III or IV. We used the raw data (abso lute rCBF parametric maps) and the adjusted rCBF images in relative flow di stribution (normalization of global CBF for each subject to 50 mL/100 g/min with proportional scaling) to compare these groups with SPM. Results: In p atients with stage I or II Parkinson's disease, we found a diffuse decrease in absolute rCBF in the whole brain with sparing of the central gray matte r, hippocampus and right lower temporal lobe compared with healthy voluntee rs. Adjusted rCBF increased in both putamina and the right hippocampus; In patients with stage III or IV disease, rCBF decreased throughout the whole brain. Adjusted rCBF increased bilaterally in the putamina, globi pallidi, hippocampi and cerebellar hemispheres (dentate nuclei) and in the left vent rolateral thalamus, right insula and right inferior temporal gyrus. Conclus ion: SPM analysis showed that significant rCBF changes in Parkinson's disea se accompanied disease progression and related to disease pathophysiology i n the functional architecture of thalamocortex-basal ganglia circuits and r elated systems.