Neuroscience · Year 2 · from Neuroscience
Case 1: Normal Pressure Hydrocephalus
Patient Presentation
Demographics: 74-year-old male
Chief Complaint: Progressive difficulty walking and memory problems over 6 months
History of Present Illness: The patient's wife reports that her husband has had increasingly unsteady walking over the past 6 months. He shuffles his feet and has fallen twice, once in the bathroom and once trying to walk to the kitchen. She also notes he has become forgetful, especially for recent events, and seems "slowed down" mentally. Over the past 2 months, he has had several episodes of urinary incontinence, which is new for him. He attributes it to "not making it to the bathroom in time." There is no history of headaches, vision changes, or recent head trauma.
Physical Examination:
- Vital signs: BP 138/82, HR 68, T 36.8C
- General: Pleasant elderly male, appears his stated age
- Neurological:
- Mental status: Oriented to person and place, knows the month but not the date; slow to respond; scores 22/30 on MoCA (impaired in delayed recall and executive function)
- Cranial nerves: Intact
- Motor: 5/5 strength throughout; no rigidity
- Sensory: Intact to light touch and vibration
- Reflexes: 2+ throughout, Babinski absent bilaterally
- Gait: Wide-based, shuffling gait with short steps; appears as if feet are "stuck to floor" (magnetic gait); difficulty initiating steps; no arm swing; cannot perform tandem walk
Workup:
- CT head: Ventriculomegaly with disproportionate enlargement of ventricles compared to sulci; Evans ratio 0.38 (>0.30 indicates ventriculomegaly); no periventricular edema
- MRI brain: Enlarged ventricles out of proportion to cortical atrophy; no parenchymal lesions; aqueduct patent; some flow void present
- Large-volume lumbar puncture (tap test): Opening pressure 170 mm H2O (upper normal); 40 mL CSF removed; protein and glucose normal; no cells
- Post-LP gait assessment: Significant improvement in gait 4 hours after LP - shorter steps replaced by near-normal stride, reduced shuffling, able to turn more easily
Diagnosis: Idiopathic normal pressure hydrocephalus (iNPH)
Treatment:
- Ventriculoperitoneal (VP) shunt placement with programmable valve
- Physical therapy for gait training
- Occupational therapy for cognitive strategies
Clinical Course: Two weeks after VP shunt placement, the patient's wife reported dramatic improvement in walking. He was no longer shuffling and had not fallen. Urinary urgency improved significantly, though he still had occasional accidents if he delayed going to the bathroom. Cognitive testing at 3-month follow-up showed improvement in MoCA score to 26/30. At 6-month follow-up, he was living independently with his wife and participating in daily activities.
Clinical Pearl: The classic triad of NPH is "wet, wacky, and wobbly" - urinary incontinence, dementia, and gait apraxia. The gait disturbance is typically the earliest symptom and most responsive to treatment. The "tap test" (large-volume LP with pre- and post-assessment) helps predict shunt response. Unlike other causes of ventriculomegaly, NPH shows disproportionate ventricular enlargement compared to sulcal widening, distinguishing it from ex vacuo hydrocephalus due to atrophy.