Behavioral Variant Frontotemporal Dementia with Corticobasal Degeneration Pathology: Phenotypic Comparison to bvFTD with Pick’s Disease

University of California San Francisco, San Francisco, CA, USA.
Journal of Molecular Neuroscience (Impact Factor: 2.34). 09/2011; 45(3):594-608. DOI: 10.1007/s12031-011-9615-2
Source: PubMed


Patients with corticobasal degeneration (CBD) pathology present with diverse clinical syndromes also associated with other neuropathologies, including corticobasal syndrome, progressive nonfluent aphasia, and an Alzheimer's-type dementia. Some present with behavioral variant frontotemporal dementia (bvFTD), though this subtype still requires more detailed clinical characterization. All patients with CBD pathology and clinical assessment were reviewed (N = 17) and selected if they initially met criteria for bvFTD [bvFTD(CBD), N = 5]. Available bvFTD patients with Pick's [bvFTD(Pick's), N = 5] were selected as controls. Patients were also compared to healthy older controls [N = 53] on neuropsychological and neuroimaging measures. At initial presentation, bvFTD(CBD) showed few neuropsychological or motor differences from bvFTD(Pick's). Neuropsychiatrically, they were predominantly apathetic with less florid social disinhibition and eating disturbances, and were more anxious than bvFTD(Pick's) patients. Voxel-based morphometry revealed similar patterns of predominantly frontal atrophy between bvFTD groups, though overall degree of atrophy was less severe in bvFTD(CBD), who also showed comparative preservation of the frontoinsular rim, with dorsal > ventral frontal atrophy, and sparing of temporal and parietal structures relative to bvFTD(Pick's) patients. Despite a remarkable overlap between the two patient types, bvFTD patients with underlying CBD pathology show subtle clinical features that may distinguish them from patients with Pick's disease neuropathology.

    • "MAPT mutations have been associated with symmetrical anterior temporal lobe atrophy, with less pronounced frontal atrophy than that seen in Pick's disease (Whitwell et al., 2005). In PSP and CBD, there is atrophy of the posterior frontal regions, particularly involving the premotor regions, but in CBD, the atrophy is typically more widespread and asymmetrical, and the parietal region can be involved (Rankin et al., 2011). "

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