Abstract
Spontaneous thrombosis of a giant intracranial aneurysm is a known occurrence; however, this aneurysm is rare wherein the thrombus extends to the parent artery and leads to occlusion. We report a case of a giant intracavernous internal carotid artery aneurysm with thrombosis and pseudo-occlusion of the internal carotid artery. A 55-year-old woman was incidentally found with a giant cerebral aneurysm; however, she had no symptoms. An angiogram and balloon occlusion test (BOT) were performed. The first angiogram revealed no thrombus in the aneurysm. Seven days after the BOT, the patient suddenly developed symptoms such as headache, vomiting, right eye pain, and right ptosis. The second angiogram showed an aneurysm that was barely visible and a slow flow of the internal carotid artery. Magnetic resonance imaging (MRI) revealed an infarction in the right middle cerebral artery territory. We considered the infarction as embolic because the collateral circulation was sufficient in this case. As the BOT showed a slight flow reduction (90% on the contralateral side), we performed a ligation of the internal carotid artery combined with superficial temporal artery to the middle cerebral artery branch M4 (STA-M4) bypass. Postoperatively, the right eye pain and ptosis disappeared. No neurological deficits and infarctions were observed. In this case, the temporary occlusion of the internal carotid artery through the BOT may have caused hemodynamic changes and affected thrombus formation.
