RCBF SPECT IN PARKINSONS-DISEASE PATIENTS WITH MENTAL DYSFUNCTION

Functional imaging of the brain using SPECT provides information corre lative to the alterations of regional blood flow. In this paper we rev iew the literature pertaining to SPECT in Parkinson's disease with and without dementia and depression. Parkinson's disease itself is not as sociated with a consistent pattern of cerebral blood flow alterations in the basal ganglia, but reduced parietal blood flow is more often re ported. The heterogeneity of blood flow changes possibly reflects the multifactorial pathophysiology of the disease. In demented Parkinson's disease patients frontal hypoperfusion is often found or bilateral te mporoparietal deficits, probably indicative of concommitant Alzheimer' s disease. The SPECT studies undertaken in depressed patients with and without Parkinsons's disease show highly conflicting and inconsistent results, probably due to methodological and diagnostic flaws (especia lly the inclusion of demented Parkinson patients). Several lines of re asoning point to a prefrontal dysfunction and future SPECT studies are planned to study this region in non-demented Parkinson's disease pati ents with and without major depression.