Functional Outcomes After Treatment of Posterior Inferior Cerebellar Artery Aneurysms

Abstract

Aneurysms of the posterior inferior cerebellar artery (PICA) are a rare cause of subarachnoid hemorrhage. Treatment for this type of aneurysm may be microsurgical clipping or endovascular. This decision is based on patient characteristics, aneurysm location and dimensions, along with surgeon and institutional experience. In this study we aim to assess the outcomes of surgical and endovascular treatment of PICA aneurysms. Methods We retrospectively reviewed the charts of 52 patients who were admitted to Vancouver General Hospital for ruptured or symptomatic PICA aneurysms between 2005 and 2015. Modified Rankin scores were assigned at the time of discharge and at two subsequent follow-up time points. The mean short-term follow-up period post-operatively was 11.1 months and the mean long-term follow-up period was 19.3 months. Clinical and radiological characteristics were collected for all patients. Results Of the 52 patients, two died prior to obtaining treatment. Of the 50 patients who were treated for their PICA aneurysm, 39 presented with subarachnoid hemorrhage while 11 had symptomatic unruptured PICA aneurysms. Overall, 11 patients had endovascular treatment (coil embolization) while 39 patients underwent microsurgical clipping/trapping of the aneurysm. At the time of hospital discharge, patients in the microsurgical group trended towards a better the modified Rankin Scale score (2.3) compared to the endovascular group, though this did not reach significance (3.0) (p=0.20). The long-term score in the endovascular group (1.6) was also comparable to the microsurgical group (1.9) (p=0.55). Conclusion While the early outcomes in patients treated endovascularly appear better, there is no statistically significant difference in outcomes between the microsurgical and endovascular treatment groups at shortand long-term follow-up.

Microsurgical treatment of posterior inferior cerebellar aneurysms based on angioarchitecture supplemented by high-resolution vessel wall MRI: a case series report

“…Surgical treatment of PICA aneurysms can achieve good results (tables 1 and 2) and the individualised surgical strategy varies according to the aneurysm’s segmental location and morphology (figure 1). 14 16 18 32 39 However, although DSA remains the gold standard for aneurysm diagnosis and angioarchitecture assessment, it does not provide the aneurysmal wall structure data that HR-VW MRI does 17. We found a significant difference between DSA and HR-VW MRI aneurysm size measurements, with MRI arriving at a larger size.…”

“…After aneurysm exposure and inspection, direct clipping or clip reconstruction was preferentially performed. If the aneurysm was unclippable due to complexity, bypass and trapping was considered, especially for proximal aneurysms associated with critical brainstem perforators 1 5 9 11–14 18 20 22–24 26 29 32–38. We preferred intracranial–intracranial (IC-IC) bypass over extracranial–intracranial (EC-IC) bypass when possible.…”

Challenging Endovascular Treatment of Ruptured Proximal Posterior Inferior Cerebellar Artery Aneurysm: A Case Report

“…As a result, the surgical management of PICA aneurysms carries a high risk, regardless of whether the patient has ischemia or SAH. 8,9 Endovascular therapy of PICA aneurysms has resulted in more favorable outcome because of the lower risk in injuring neighboring lower cranial nerves as well as the PICA perforating branches. Coil embolization is still the preferred treatment option for narrow-necked saccular aneurysms.…”

Far-lateral approach without C1 laminectomy for microsurgical treatment of vertebral artery and proximal posterior inferior cerebellar artery aneurysms: Experience from 48 patients

“…They concluded no significant difference in outcomes between the microsurgical and endovascular treatment groups at short- and long-term follow-ups. 32 Del Maestro et al reported 25 (60% rupture) patients with PICA aneurysms treated with microsurgery (92% by direct clipping and 8% by PICA–PICA bypass with trapping) via the far-lateral approach, and 60% of the patients achieved good outcomes. 33 …”