Hydrocephalus, ventriculomegaly and the vegetative state: a review.

The revised guidelines from the Royal College of Physicians make it clear that structural problems such as hydrocephalus should be excluded before the diagnosis of vegetative state (VS) can be made. Ventriculomegaly is common after severe head injury but the distinction between atrophy and potentially treatable hydrocephalus cannot be made on the basis of conventional computerised tomographic (CT) or magnetic resonance (MR) scanning alone--physiological measurements of intracranial pressure (ICP) and cerebrospinal fluid (CSF) outflow resistance may be helpful. These techniques are reviewed together with the limited literature available that documents the effect of CSF diversion on outcome in "vegetative" patients.