[A ruptured cerebral aneurysm of the fronto-orbital artery and a coexisting anastomosis with the anterior ethmoidal artery--a case report].

The authors present a case with a ruptured saccular aneurysm of the left fronto-orbital artery and the coexisting anastomosis with the left anterior ethmoidal artery, accompanied by subarachnoid hemorrhage and intracerebral hematoma in the left frontal lobe. A 44-year-old male, whose past history had been uneventful, was admitted complaining severe headache and vomiting, followed by confusion. CT examinations revealed subarachnoid hemorrhage and intracerebral hematoma in the left frontal lobe. Left carotid angiograms disclosed a saccular aneurysm described above. Emergency operation in a state of grade 3 according to Hunt and Kosnik revealed a saccular aneurysm and its parent artery which was thought to be proximally a left fronto-orbital artery and distally a left anterior ethmoidal artery, which was seen to penetrate the anterior cranial fossa at the lamina cribrosa. Then the aneurysm was excised following clipping of the neck. Thereafter, the patient showed favorable recovery. The histological examination revealed absence of the media and the internal elastic lamina in the wall of the aneurysm with slight infiltration of round cells. Generally speaking, distal anterior cerebral artery aneurysms, which arise on branches beyond the anterior communicating artery, occupy 2-5% of all cerebral aneurysms, and most of them are found at the branching site of the pericallosal artery. As far as the authors know, there was few or no report referring to the aneurysm arising on the fronto-orbital artery, as shown in this case. Also, as for the aneurysm arising on the anterior ethmoidal artery, there are a few reports.(ABSTRACT TRUNCATED AT 250 WORDS)