Visual hallucinations, white matter lesions and disease severity in Parkinson's disease

OBJECTIVES: To determine if visual hallucinations in patients with Parkinson's disease are associated with an increased prevalence of white matter lesions. PATIENTS AND METHODS: Fifteen patients with (group 1) and 15 patients without (group 2) a history of visual hallucinations were studied. Both groups were matched for age. Magnetic resonance imaging was performed in all patients using standard T2 weighted Fast-Spin-Echo sequences. Assessment of cerebral white matter changes was performed using a modification of established criteria, with semiquantitative evaluation of periventricular and deep white matter changes. RESULTS: There was no significant group difference with regard to the total amount of white matter changes, nor was a group difference found between the amount or extent of periventricular hyperintensities or deep white matter lesions. Group 1 was significantly (P = 0.001) more disabled as evaluated by Hoehn/Yahr stage controlling for age and duration of disease. Mean increases in Hoehn/Yahr stage were not significantly greater in group 1 compared with group 2 at a 2-year follow-up examination (0.6 vs. 0.3, P = 0.166). CONCLUSION: Our data suggest that visual hallucinations are an indicator of a more aggressive course of the disease, but are not associated with a higher prevalence of global or occipital white matter lesions.