Normal Pressure Hydrocephalus: The Daily PANCE Blueprint

The answer is A. Ventriculoperitoneal shunt placement

This is normal pressure hydrocephalus, and the definitive intervention is ventriculoperitoneal shunting — a potentially reversible cause of dementia and gait failure, which is exactly why it matters that you recognize it. The classic triad is gait apraxia, urinary incontinence, and cognitive impairment (the “wobbly, wet, and wacky” mnemonic), and the magnetic, wide-based, shuffling gait is usually the FIRST symptom and the one most likely to improve after shunting. Imaging shows ventriculomegaly out of proportion to cortical atrophy, and the pressure is normal on lumbar puncture — the name is literal.

The finding that seals it is the large-volume tap test: objective gait improvement after removing 30 to 50 mL of cerebrospinal fluid is the best predictor of shunt response. That is a diagnostic maneuver, not a treatment, which is why repeating lumbar punctures indefinitely is not an answer — it is a temporizing measure that never addresses the underlying impaired cerebrospinal fluid absorption.

Donepezil is the trap, and it is the error that costs patients years: NPH is routinely misdiagnosed as Alzheimer disease and treated with a cholinesterase inhibitor. The discriminator is the sequence — in NPH gait trouble comes first and the memory problem is mild, whereas in Alzheimer disease memory loss comes first and gait stays normal until late. Acetazolamide reduces cerebrospinal fluid production in idiopathic intracranial hypertension, a different disease with high pressure and papilledema. Carbidopa-levodopa targets Parkinson disease, which shares a shuffling gait but presents with resting tremor, rigidity, and asymmetric onset — explicitly absent here.