Contribution of PET studies in diagnosis of corticobasal degeneration.

Five patients with clinical features of corticobasal degeneration (CBD) were studied with PET imaging. The main clinical findings included a unilateral extrapyramidal motor disorder, without significant response to levodopa, as well as clumsiness, dysarthria, apraxia and a clear asymmetry of neurological signs. PET studies with (18)F-labeled 2-deoxy-2-fluoro-D-glucose disclosed mainly a significant hypometabolism in the thalamus and motor cortex controlateral to the more affected limbs. Additional relationships between individual clinical signs and PET data were also found. We concluded that PET findings supported the clinical diagnosis of CBD, although the specific pattern related to this condition needs to be more precisely defined. Further studies are especially needed to correlate clinical data and PET results with pathological examination.