A 70-year-old with progressive dementia, rigidity, and supranuclear gaze palsy shows tau-positive neurofibrillary tangles predominantly in the subthalamic nucleus, globus pallidus, and periaqueductal gray. Cortical involvement is sparse. This pattern corresponds to:
- A Progressive supranuclear palsy (PSP) ✓
- B Alzheimer's disease
- C Corticobasal degeneration
- D Pick's disease (frontotemporal lobar degeneration with tau)
Correct answer: A. Progressive supranuclear palsy (PSP)
Explanation
PSP is a 4R tauopathy characterized by tau deposits (neurofibrillary tangles and tufted astrocytes) predominantly in subcortical structures including the subthalamic nucleus, globus pallidus, substantia nigra, and periaqueductal gray. The clinical hallmark is vertical gaze palsy. Alzheimer's shows widespread cortical tau with amyloid plaques; corticobasal degeneration shows asymmetric cortical tau with ballooned neurons; Pick's disease has Pick bodies (globose tau inclusions) in frontal and temporal cortex.
Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.