Parkinsonism in patients with vascular dementia: Clinical, computed- and positron emission-tomographic findings

Purpose: The present study investigates the vascular nature of parkinsonian features in patients with 'probable' vascular dementia. Patients and Methods: Forty patients with vascular dementia were studied with positron emission tomography (PET) using the steady state technique with O-15 in order to assess regional cerebral blood flow (rCBF), regional oxygen extraction rate (rOER) and regional metabolic rate for oxygen (rCMRO(2)) in different brain regions. The findings in 10 patients with (VaDP) were compared to 30 without parkinsonism (VaD). Results: The clinical and computed tomographic findings in the parkinsonian patients were similar to those described in the literature as probable vascular parkinsonism. The PET results showed decreased rCBF and rCMRO(2) in the frontal and parietal cortices and in the striatum of the VaDP compared to the VaD group. The decrease of rCBF and rCMRO(2) in frontal and parietal cortices is due to the more severe mental changes in the VaDP group. In the VaDP patients rCBF and rCMRO(2) were more decreased and rOER increased in the striatum contralateral to the most affected parkinsonian side. Conclusion: Our PET findings show that local ischemic changes in the striatum contribute to parkinsonism in vascular dementia patients. Copyright (C) 2001 S. Karger AG, Basel.