Cerebral blood flow correlates of higher brain dysfunctions in corticobasal degeneration.

To investigate clinicoanatomic correlations of higher brain dysfunctions in corticobasal degeneration, regional cerebral blood flow (rCBF) was semiquantitatively measured with single-photon emission computed tomography in 9 patients with corticobasal degeneration and 12 age-matched control subjects. The patients showed significant reductions of relative tracer uptake in widespread cortical areas, as well as the basal ganglia and thalamus. Interhemispheric difference of hypoperfusion was significant in the sensorimotor and posterior parietal cortices. Asymmetric limb apraxia and cortical sensory disturbance corresponded to either sensorimotor cortical or posterior parietal cortical hypoperfusion or both. Compared with the patients without dementia, those with dementia showed significant reductions of relative rCBF in the inferior prefrontal region in the more affected hemisphere. The unique correlation of cortical signs with regional hypoperfusion may be useful in distinguishing between corticobasal degeneration and other neurodegenerative diseases.