Hydrocephalus as a cause of dementia: evaluation by computerised tomography and intracranial pressure monitoring.

To identity those patients with hydrocephalus as a basis for their presenile dementia it is suggested that such patients be screened non-invasively by CT scan. If there is ventricular dilatation and small cortical sulci, intracranial pressure should be monitored for 48 hours to detect `B' waves. Patients with significant `B' waves (10 mmHg) for at least two hours in the day might benefit from a shunt.