A 65 year old gentleman presents with difficulty in walking for 1 year, forgetfulness for 6 months and urinary incontinence for 5 months. These problems have progressed slowly over time. The difficulties in walking included hesitation in initiating steps, slowness in gait, and difficulty in turning around corners. He use to freeze at times while walking. He also had difficulty in finding words and handling money, and started forgetting recent events and names of distant relatives. He was diagnosed with hypertension 5 years ago, which is well controlled on atenolol. His medical history is otherwise unremarkable.
There is symmetric dilatation of all ventricles; the Evans' Index is 0.44. The sulci are preserved and perihippocampal fissures are normal. There are no significant white matter abnormalities.
50 ml of CSF drained. Opening pressure: 190 mm of water. MMSE following Tap test: 27/30; velocity of gait: faster
The EEG appears normal.
WBC: 9,500/mm3 (4000-11000) Hb: 13g/dL (11-18) Plt: 260,000mm3 (150,000-400,000)