Corticobasal degeneration cognitive syndrome — SCE Neurology MCQ

Correct answer: A — The phenotype supports corticobasal syndrome, but neither the MRI nor dopamine-transporter scan determines the underlying pathology

Corticobasal syndrome is a clinical phenotype and is not synonymous with corticobasal degeneration at pathology. Asymmetric perirolandic atrophy supports the diagnosis, but its absence would not exclude it. An abnormal dopamine-transporter scan supports presynaptic dopaminergic dysfunction yet cannot reliably distinguish corticobasal syndrome from other degenerative parkinsonian disorders or identify the proteinopathy. Alien-limb phenomena, apraxia and cortical sensory loss are characteristic cortical features. The key learning point is therefore to separate a syndromic clinical diagnosis from a definitive pathological label.

Reference: Corticobasal syndrome: a practical guide: https://pn.bmj.com/content/21/4/276