Arterial reconstruction by direct surgical clipping of a basilar artery dissecting aneurysm after failed vertebral artery occlusion: technical case report and literature review

Dissecting aneurysms of the basilar artery are rare lesions with significant morbidity and mortality. Their management is controversial and often difficult. Although the rebleeding rate is high, clip reconstruction carries prohibitive risk because of the damage to the parent vessel induced by the dissection and the lack of tissue to gather. An enlarging pseudoaneurysm in the chronic phase, however, may have sufficient tissue for clip reconstruction. We present a case in which this strategy was used successfully. A 45-year-old woman presented 3 months after an initial presentation with a subarachnoid hemorrhage from a dissecting aneurysm of the basilar trunk at an outside institution. The aneurysm had grown compared with previous angiograms. The dominant vertebral artery was sacrificed. Despite this, the aneurysm continued to enlarge. Given the progressive enlargement of the aneurysm, the decision was made to proceed with arterial reconstruction by direct surgical clipping of the saccular component of the dissecting aneurysm. The patient made an excellent recovery with a durable result. Although clipping an intracranial pseudoaneurysm in the acute phase may carry a prohibitive risk, clipping such an aneurysm in the chronic phase may occasionally be warranted. To our knowledge, this is the first case reported in the literature in which direct surgical clipping was used as the primary mode of treatment for a basilar artery dissecting aneurysm that enlarged despite occlusion of the dominant vertebral artery. We review the literature on this rare pathological entity and discuss our management strategy.