Safety of carotid ligation and its role in the management of intracranial aneurysms.

By using measurements of cerebral blood flow and internal carotid artery pressure it is possible to select patients in whom carotid ligation can be performed with a very low risk of post-operative cerebral ischaemia. A study has been carried out in 100 patients comparing this method with clinical predictions of the type used in aneurysm surgery based on age of the patient, arterial hypertension, time from latest subarachnoid haemorrhage, and neurological status on a modified Botterell scale. These clinical factors were found to be of little value in predicting which patients would and would not develop cerebral ischaemia after carotid occlusion.