Subarachnoid hemorrhage associated with angiographic "stenotic" or "occlusive" lesions in the carotid circulation

It has been assumed that dissecting aneurysms presenting with subarachnoid hemorrhage (SAH) are extremely rare in the carotid circulation. This may be partially attributed to the difficulty in their diagnosis. The documented angiographic findings include arterial narrowing or occlusion. The purpose of the present study is to investigate the origin of SAH associated with "stenotic" or "occlusive" lesions, which might have been categorized into "SAH of unknown origin."

Between April 1984 and June 1994, 580 patients underwent thorough angiographic investigation to determine the origin of their nontraumatic SAH. Of these patients, five patients had as the only lesion suspected as the source of SAH a single stenosis or occlusion in the carotid circulation that was revealed at the first angiography performed within 48 hours following the onset. We detail these five patients and discuss the current strategy for the treatment of SAH associated with stenotic or occlusive lesions in the carotid circulation.

Arterial narrowing or occlusion were located in the internal carotid artery (ICA) in two patients, in the middle cerebral artery (MCA) in two patients, and in the posterior communicating artery in one patient. Three patients underwent operation (circumferential wrapping with cotton gauze), and dissecting aneurysms were confirmed in all of them. They all attained good recovery without rebleeding over a long-term period. Two patients died of fatal rebleeding on day 8 and on day 9 while awaiting the second angiography. In one of the patients with ICA stenosis, autopsy revealed a lacerated ICA without a definite saccular aneurysm. In the last patient with M2 occlusion, dissecting aneurysm was strongly suspected from the clinical course.

To prevent early fatal rebleeding, exploratory craniotomy for angiographic stenotic and occlusive lesions associated with SAH may be justified if all underlying conditions are met, because they may likely include dissecting aneurysms: (1) single stenotic or occlusive, (2) surgically accessible, and (3) consistent with the localization of SAH from CT scan.