Commonly, once the dissection of vertebral artery (VA) occurs, subarachnoid hemorrhage or ischemic change happens with severe headache or neurological deficits .However, there are some cases of dissecting aneurysm with headache alone or no symptoms .
Although conservative therapy is recommended, natural history of such dissecting aneurysms remains unclear. Therefore, periodic follow-up of neuroimaging is necessary to detect the changes leading to extension of dissection earlier. An occlusion of both dissecting aneurysm and VA occurred after tumor removal. It was suggested that the hemodynamic change by
intraoperative manipulation for the tumor and surrounding edematous brain causes the occlusion of dissecting aneurysm. Total tumor removal was via the suboccipital retrosigmoid
approach. Intraoperatively, the intramural hematoma of the dissecting aneurysm appeared to be old and unruptured, and we left it untreated. Cerebellar swelling was observed. The findings of neuroradiological images, such as fusiform dilatation and retention of contrast medium on angiogram and intramural hematoma on magnetic resonance imaging made a diagnosis of dissecting aneurysm. We made our diagnosis because the angiogram showed a fusiform dilatation and contrast retention. Although we incidentally found a dissecting aneurysm on preoperative angiographs and MRI scans, we posit its asymptomatic pre-existence, because there were no previous episodes severe headache, and no evidence of subarachnoid haemorrhage (SAH) or infarction on MRI.
Yasuhiko Hayashi, Occlusion of an Incidentally-Found Dissecting Aneurysm of the Vertebral
Artery at Removal of a Jugular Tubercle Meningioma
Last date updated on June, 2014