A 66-year-old man has progressive bradykinesia, axial rigidity, frequent falls within the first year, and impaired voluntary downgaze with preserved reflex eye movements on doll's head maneuver. Levodopa gives minimal benefit. The most likely diagnosis is:

• A Idiopathic Parkinson's disease
• B Drug-induced parkinsonism
• C Multiple system atrophy, parkinsonian type
• D Progressive supranuclear palsy ✓

Explanation

Early falls plus vertical supranuclear gaze palsy, in which voluntary gaze fails but reflex vestibulo-ocular movements are preserved, is the signature of progressive supranuclear palsy (Steele-Richardson-Olszewski disease), a tauopathy with poor levodopa response. Multiple system atrophy is distinguished instead by prominent autonomic failure and cerebellar signs, both absent here.

Reference: Harrison's Principles of Internal Medicine, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.