A 73-year-old man with an unremarkable past medical history presented after a 3-year history of progressive forgetfulness and poor balance as well as recent onset of urinary incontinence. Examination showed impaired memory and difficulties with calculations and visuospatial skills. Language was normal. The patient’s Mini-Mental State Examination score was 23/30. The rest of the neurologic examination was notable for diminished postural reflexes and abnormal gait with signs of gait apraxia. Laboratory tests did not reveal any treatable cause of dementia. X-ray computed tomography demonstrated enlarged ventricles and hypodensity of the white matter. Lumbar puncture was performed with normal opening pressure, and 30 cc of CSF were collected. CSF analysis was normal. The patient’s gait transiently improved with better stride and improved postural reflexes.
A diagnosis of normal-pressure hydrocephalus was made based on the presence of the clinical triad and typical neuroimaging studies. The patient underwent ventriculoperitoneal shunting. X-ray computed tomography obtained after the operation was unchanged from his previous imaging.
One month after shunt placement, the patient experienced significant improvement in gait and bladder control. His cognition also improved, and his repeat Mini-Mental State Examination score was 28/30. A follow-up CT demonstrated reduction of hypodensities in the periventricular white matter. The ventricular size was not significantly changed.