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Updated: May 27, 2026

Microsurgical Clip Obliteration of Middle Cerebral Aneurysm Using Intraoperative Flow Assessment
Published on: September 25, 2009
Multiple non-branching dissecting aneurysms of the mid-basilar trunk presenting with sequential subarachnoid
Archie Defillo1, Eric S Nussbaum, Andrea Zelensky
1Department of Neurosurgery, National Brain Aneurysm Center, Health East St. Joseph's Hospital, St. Paul, MN 55102, USA.
Objective:
We describe a rare case of a patient with subarachnoid hemorrhage (SAH) due to a ventral dissecting mid-basilar aneurysm that was treated surgically. One week after surgery, the patient experienced sudden deterioration due to a new SAH caused by the development of a new aneurysm of the basilar trunk distinct from the previously clipped aneurysm.
Case Description:
A 54-year-old woman with acute subarachnoid hemorrhage was found to have a small, broad-based aneurysm arising from the ventral aspect of the mid-basilar artery. This complicated lesion was treated with a microsurgical clipping via a translabyrinthine pre-sigmoidal sub-temporal approach. One week postoperatively, the patient suffered a new SAH and was found to have developed a distinct basilar artery aneurysm. The patient was returned to the Operating Room for microsurgical clipping via the previous craniotomy. After surgery, the patient made a slow, but steady, recovery. She underwent repeated angiographic imaging, demonstrating a stable appearance. Two years post surgery, the patient had returned to work and had no obvious neurological deficit, with the exception of unilateral iatrogenic hearing loss.
Conclusion:
We describe a rare case of multiple aneurysms originating in relation to a mid-basilar dissection, resulting in multiple episodes of SAH. These are difficult and dangerous lesions that can be treated with open microsurgical reconstruction or possibly via an endovascular approach. The intricate location of the lesions poses a particular challenge to neurosurgeons attempting to directly treat mid-basilar lesions.
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