SINGLE-PHOTON EMISSION COMPUTED TOMOGRAPHIC BLOOD-FLOW AND MAGNETIC-RESONANCE VOLUME IMAGING OF BASAL GANGLIA IN HUNTINGTONS-DISEASE

Objective: To examine basal ganglia dysfunction and atrophy in patient s with mild to moderate Huntington's disease, with correlation of imag ing measures with clinical and neuropsychological measures. Design: Su rvey study in patients with Huntington's disease and matched controls, with imaging measures being evaluated by investigators unaware of the diagnosis. Setting: Baltimore Huntington's Disease Project, The Johns Hopkins Hospital, Baltimore, Md. Patients and Other Participants: Sub jects included 10 patients with mild to moderate Huntington's disease and nine healthy age-matched control subjects. Main Outcome Measures: Imaging measures included single photon emission computed tomographic regional cerebral blood flow in caudate, putamen, and thalamus, and ma gnetic resonance imaging measures of caudate and putamen volumes and b icaudate ratios. Patients underwent neurologic and mental status exami nations and neuropsychological tests. Results: The measure with the gr eatest difference between patients and control subjects was mean putam en volume, reduced 54.3% in patients, with no overlap between groups ( P<.001). Of the cerebral blood flow measures, caudate showed the great est difference (21.5% decrease; P<.001). Quantitative neurologic index es of disease severity correlated with both putamen measures (P<.03), while Mini-Mental State Examination scores correlated with caudate vol ume (P<.02). Bicaudate ratio correlated with both clinical measures an d was the best index of neurologic deterioration (r=.95; P<.001), whil e global atrophy (measured by cerebrospinal fluid percentage) was the best correlate of several neuropsychological tests, such as the Trail Making Test (r=.93; P<.001). Conclusions: Volumetric measurement of pu tamen best discriminated patients with Huntington's disease from healt hy subjects. Measures of caudate atrophy or single photon emission com puted tomographic measures performed less well. Neurologic decline cor related best with subcortical atrophy measured by the bicaudate ratio, but neuropsychological performance best corresponded to cerebrospinal fluid percentage, a measure of global atrophy.