Normal Pressure Hydrocephalus

Overview

NPH is a condition where excess cerebrospinal fluid accumulates in the brain's ventricles, causing the classic triad: gait disturbance (magnetic gait — feet appear glued to floor), cognitive decline (subcortical dementia pattern), and urinary incontinence. Despite the name, pressure is often normal or mildly elevated. It is potentially treatable with CSF shunting.

Symptoms

• Gait disturbance (magnetic gait — short steps, feet appear glued)
• Cognitive decline (executive dysfunction, slowed processing)
• Urinary incontinence or urgency
• Balance problems

Causes

• Impaired CSF absorption (arachnoid granulations dysfunction)
• Possible subarachnoid hemorrhage, meningitis, or trauma as antecedent
• Idiopathic in many cases

Risk factors

• Age >60
• Prior subarachnoid hemorrhage or meningitis
• Head trauma
• Ventricular shunt history

Diagnosis

MRI showing ventriculomegaly out of proportion to sulcal atrophy ('DESH' — disproportionately enlarged subarachnoid space hydrocephalus)|Lumbar puncture with CSF drainage trial (temporary improvement confirms diagnosis)|Clinical triad

Treatment & management

CSF shunt placement (ventriculoperitoneal shunt — most common)|Endoscopic third ventriculostomy (alternative)|Repetitive lumbar punctures for temporary relief|Physical therapy for gait

Management is individualized and discussed with benefits, limitations, and follow-up.

Prevention & self-care

Early recognition and treatment — outcomes are best when treated early

When to seek medical attention

• Sudden worsening of symptoms
• New neurological deficits
• Failure to improve after shunt placement

Frequently asked questions