CORTICOBASAL DEGENERATION

About CORTICOBASAL DEGENERATION all are true except:

a) CBGD is characterized by frontoparietal cortical atrophy in addition to degeneration within the extrapyramidal system.
b) The disease tends to occur in those aged 60-80 years, with a mean age of onset of 63 years.
c) The substantia nigra is depigmented.
d) Lewy bodies and diffuse neuronal loss are conspicuously present ANS
e) Symptoms on long-term follow-up include focal or asymmetric rigidity, bradykinesia, postural and action tremor, and marked dystonia.

CORTICOBASAL DEGENERATION
CBGD is characterized by frontoparietal cortical atrophy in addition to degeneration within the extrapyramidal system. The disease tends to occur in those aged 60-80 years, with a mean age of onset of 63 years.Cortical atrophy of the frontal and parietal lobes has been described, with ballooned and enlarged cells seen on microscopy. The substantia nigra is depigmented. However, Lewy bodies and diffuse neuronal loss are conspicuously absent.The disease is now classified as a 4-repeat tauopathy. Neuropathologic diagnostic criteria include tau-immunoreactive lesions in neurons, glia, and cell processes. The minimal pathologic features for diagnosis are cortical and striatal tau-positive neuronal and glial lesions, especially astrocytic plaques and threadlike structures in both white matter and gray matter combined with neuronal loss both in focal cortical lesions and substantia nigra. These criteria help distinguish the disease from other tauopathies, with the exception of frontotemporal dementia and parkinsonism related to chromosome 17 mutations (FTDP-17).