Corticobasal syndrome with tau pathology

Six cases with a clinical corticobasal syndrome (progressive asymmetric apr axia and parkinsonism unresponsive to levodopa) and tau pathology were sele cted from 97 brain donors with parkinsonism. Postmortem volumetric measures of regional brain atrophy (compared with age/sex-matched controls) were co rrelated with clinical features and the degree of underlying cortical and s ubcortical histopathology. At death, no significant asymmetry of pathology was detected. All cases had prominent bilateral atrophy of the precentral g yrus (reduced by 22-54%) with other cortical regions variably affected. Sub cortical atrophy was less severe and variable. Two cases demonstrated wides pread atrophy of basal ganglia structures (44-60% atrophy of the internal g lobus pallidus) and substantial subcortical pathology consistent with a dia gnosis of progressive supranuclear palsy (PSP). The remaining four cases ha d typical pathology of corticobasal degeneration. In all cases, neuronal lo ss and gliosis corresponded with subcortical atrophy, while the density of cortical swollen neurons correlated with cortical volume loss. Atrophy of t he internal globus pallidus was associated with postural instability, while widespread basal ganglia histopathology was found in cases with gaze palsy . This study confirms the involvement of the precentral gyrus in the cortic obasal syndrome and highlights the variable underlying pathology in these p atients. (C) 2001 Movement Disorder Society.