[Internal carotid artery aneurysm in the sella turcica area simulating pituitary tumor].

A giant aneurysm of the internal artery is described which was situated in the sella and simulated hormonally inactive hypophyseal adenoma. Axial computer tomography demonstrated a hypophyseal tumour. During operation from intranasal approach through sphenoid sinus massive haemorrhage developed but was controlled with fibrin sponge. Postoperative angiography demonstrated a giant aneurysm of the internal artery situated in the sella. Although this location of aneurysm is exceptionally rare, each case of inactive hormonally pituitary adenoma should be subjected before the operation to cerebral angiography.