Brain Perfusion in Corticobasal Syndrome with Progressive Aphasia

BACKGROUND Brain perfusion may differ between patients with corticobasal syndrome (CBS) with and without aphasia. METHODS Twenty-six (9 males and 17 females; mean age 76 ± 5.3 years) patients with CBS were enrolled in the study. Brain MRI and single-photon emission computed tomography were performed in all subjects. Language was evaluated using the Standard Language Test of Aphasia. The patients were divided into two subgroups according to the presence or absence of progressive aphasia. Differences in the regional cerebral blood flow (rCBF) between the two groups were detected based on voxel-by-voxel group analysis using Statistical Parametric Mapping 8. RESULTS All patients exhibited asymmetric motor symptoms and signs, including limb apraxia, bradykinesia, and akinetic rigidity. Of 26 patients, 9 had a clinically obvious language disturbance, characterized as nonfluent aphasia. Almost all CBS patients with aphasia exhibited cortical atrophy predominantly in the left frontal and temporal lobes with widening of the Sylvian fissure on MRI. The rCBF in the left middle frontal gyrus differed significantly between CBS patients with and without aphasia. CONCLUSION CBS patients with aphasia exhibit motor symptoms predominantly on the right side and cortical atrophy mainly in the left perisylvian cortices. In particular, left frontal dysfunction might be related to nonfluent aphasia in CBS.