Cerebellar glucose metabolism in chronic aphasia

(18F)-Fluorodeoxyglucose PET was used to compare left/right cerebellar hemispheric glucose metabolism in 37 aphasic patients with left hemisphere lesions and 22 age-matched controls. Sixteen aphasic subjects showed cerebellar symmetry. Twenty-one aphasic subjects were found to have cerebellar metabolic asymmetry, which (1) resulted from an absolute reduction in local cerebral metabolic rates of glucose in the right cerebellar hemisphere; (2) was associated with left less than right glucose metabolic asymmetry in the frontal, parietal, caudate, and thalamic regions; (3) was associated with Broca's region and deep hemisphere structural damage to the internal capsule and basal ganglia; (4) related to reduced functional motor performance, spontaneous speech, naming, reading, and writing; and (5) included all Broca's aphasia subjects.