Central conduction time as an index of ischaemia in subarachnoid haemorrhage.

Central conduction time (CCT) has been measured in 12 healthy volunteers, and in 16 patients admitted to a neurosurgical unit following subarachnoid haemorrhage. Twelve of the patients were subsequently operated upon for the obliteration of an intracranial aneurysm. CCT has been found to have low standard deviation in control cases, and in the normal side following subarachnoid haemorrhage from aneurysms in the Circle of Willis, and to be prolonged during the development of ischaemic complications, either of the haemorrhage or following surgery. Evidence so far suggests that CCT may be useful as a monitor of developing ischaemia in association with surgery for subarachnoid haemorrhage.