The incidence of aneurysms from the distal superior cerebellar artery (SCA) is only 0.2% of all intracranial aneurysms.
Several surgical procedures, including parent artery occlusion, clipping of the aneurysmal neck, trapping of the bleeding site, and wrapping of the aneurysm have been proven effective in preventing rupture of a distal SCA aneurysm.
However, due to difficulty conserving all of the perforating artery and maintaining the patency of the parent artery during the surgical procedure, satisfactory surgical occlusion or trapping cannot always be performed with distal SCA aneurysms. Therefore, surgical, endovascular, and combined approaches, based on their characteristics, such as size or location, have been widely used in treatment of these aneurysms.
Little information is available on endovascular approaches in treatment of distal SCA aneurysms 1).
A study includes a comparative analysis of the SCA aneurysms treated with microsurgery and endovascular techniques at the Department of Neurosurgery, Louisiana State University Health Sciences Centre, Shreveport, Louisiana, USA along with a pooled analysis of available literature on overall outcomes in these two forms of treatment.
This retrospective study included our patients with SCA aneurysms from 2000 to 2015. Clinical outcomes were assessed by the Glasgow outcome scale (GOS) at discharge and Modified Rankin scale (mRS) at follow-up. A literature review was performed for clinical series on SCA aneurysms from 1991 to 2015 describing more than 10 patients for pooled analysis.
Among the twenty patients (microsurgery=12, endovascular=8), 66% from microsurgery and 75% from endovascular arm had good outcomes (GOS score >3 and mRS score <3) (p=0.54). Microsurgery had 88.8% complete occlusion rate as compared to 75% in endovascular treatment (p=0.45). Pooled analysis of 12 studies showed endovascular coiling is significantly associated with good clinical outcome (88.1% vs 76.9%; p=0.003). Microsurgery provides better radiological outcome in terms of complete occlusion rate (90.1% vs 67.4%; p=0.0001) and lower recurrence rate (0% vs 11.8%; p=0.005).
Individual series on SCA aneurysms have not proven any outcome benefit of either treatment modality over the other. However, pooled analysis suggests that microsurgery provides complete and sustainable aneurysm occlusion, though with an inferior clinical outcome 2).