Posterior cortical brain dysfunction in cognitively impaired patients with Parkinson’s disease – a rCBF scintigraphy study

OBJECTIVES: The aim of the study was to visualize cortical function in Parkinson's patients with various degrees of cognitive impairment. MATERIALS AND METHODS: Thirty-seven patients with Parkinson's disease and three with Parkinson plus syndromes underwent cognitive assessment and rCBF using (99m)TC-HMPAO-SPECT. RESULTS: Almost no regional reductions in cerebral blood flow were seen in patients without cognitive impairment (n = 16). Limited, mainly posterior, blood flow reductions were seen in patients with mild cognitive impairment (n = 14), whereas the reductions were extensive and bilaterally symmetric, involving both anterior and posterior brain regions in patients with dementia (n = 10). CONCLUSIONS: The findings suggest a widespread cortical, mainly posterior type of dysfunction and a relationship between the degree of cognitive impairment and the magnitude of the dysfunction.