Surgical distal outflow occlusion for the treatment of complex intracranial aneurysms: experience with 18 cases

Selected intracranial aneurysms still require parent artery occlusion. Although such occlusion is usually performed proximal to the aneurysm, in rare instances, it may be difficult or impossible to access the proximal parent artery.

To describe the use of parent artery sacrifice distal to the aneurysm (distal outflow occlusion) in the management of complex aneurysms not amenable to standard microsurgical or endovascular therapy.

We reviewed a comprehensive database of intracranial aneurysms evaluated between 1997 and 2013. Hospital records, neuroimaging studies, operative reports, and outpatient clinic notes were examined for all patients treated with distal outflow occlusion.

Eighteen patients (11 women, 7 men; ages 28-69 years) underwent surgical distal outflow occlusion. Eight (44%) underwent concomitant distal revascularization. Intraoperative and delayed postoperative angiography was performed in every case. Nine presented with acute subarachnoid hemorrhage, 1 had a remote bleeding episode. The remaining lesions were unruptured; 3 were discovered incidentally, 3 had symptomatic cerebral edema, 1 had transient ischemic attacks, and 1 had cranial neuropathy. The average follow-up period was 6.5 years; no patient was lost to follow-up review. Two aneurysms required delayed endovascular treatment. Overall, 16 patients achieved a good outcome, 1 had moderate disability, and 1 died.

We describe our experience with distal outflow occlusion in the treatment of complex aneurysms not amenable to primary clip reconstruction or endovascular therapy. This technique has been described in very limited fashion in the past and may be particularly useful for patients requiring parent artery occlusion when proximal occlusion is challenging or impossible.