Role of microsurgery for treatment of posterior circulation aneurysms in the endovascular era

Microsurgical treatment of posterior circulation aneurysms: an institutional experience from Nepal

Background

Management strategies and outcomes of patients with posterior circulation aneurysms are varied due to uncertainty in the optimal treatment modality and limited experience of neurosurgeons. Data are scarce regarding patients with posterior circulation aneurysms from developing countries. This study aims to describe the clinical characteristics, management strategies and outcome of patients with these aneurysms treated microsurgically in an academic institute in Nepal.

Methods

The clinical records of patients confirmed to have posterior circulation aneurysms treated microsurgically between July 2014 and July 2022 were retrospectively reviewed. Demographic and clinical characteristics, morphometric characteristics of aneurysms, management strategies, postoperative complications, and 1-year outcomes were described.

Results

Out of 220 aneurysms in 190 patients, 20 were posterior circulation aneurysms. The median age of the patients was 43 (15-60) years. All were ruptured aneurysms. The admission Hunt and Hess grades of 18 (90%) patients were less than or equal to III. The posterior inferior cerebellar artery (8) was the commonest location. The postoperative complications rate was 20%, with the overall mortality of 10%. 80% of patients had a favourable outcome at 1-year follow-up.

Conclusions

The patient characteristics and outcome are comparable with those described in the literature from other countries. With an individualized and careful selection strategy, our results are satisfactory despite fewer operations.

Interposition Intracranial-Intracranial Bypass Based on Anterior Cerebral Artery A1 Donor Anastomosis: Technical Advances, Outcomes, and Literature Review

BACKGROUND

The bypass technique is important for treating complex intracranial aneurysms and is infrequently performed. Intracranial-intracranial (IC-IC) bypass has shown many advantages in recent years.

OBJECTIVE

To review the techniques and outcomes of bypass based on anterior cerebral artery (ACA) A1 donor anastomosis in patients with intracranial aneurysm.

METHODS

We retrospectively reviewed the clinical and imaging data, surgical strategy, and follow-up outcomes of 7 patients treated from 2019 to 2022. Neurological function was assessed by the modified Rankin Scale (mRS). A literature review was performed using PubMed.

RESULTS

All 7 patients (3 male patients and 4 female patients; mean age, 50.4 ± 15.5 years) underwent aneurysm trapping or clipping using interposition IC-IC bypass based on ACA-A1 donor anastomosis. There were 6 middle cerebral artery (MCA) aneurysms and 1 posterior cerebral aneurysm in the series. One IC-IC bypass failed and was changed to extracranial-intracranial bypass. Three patients with MCA M1 aneurysm showed perforator-related infarction after the operation. The modified Rankin Scale score was 0 in 4 patients, 2 in 2 patients, and 1 in 1 patient. The long-term graft patency rate was 100%.

CONCLUSION

Interposition IC-IC bypass based on ACA-A1 donor anastomosis provides an effective way to achieve blood flow reconstruction in the treatment of complex aneurysms. This technique provides better caliber and volume compatibility and diminishes neck incision. Perforator-related infarction was the main complication because of involvement of the MCA M1 aneurysm location. Proximal clipping is preferred to avoid perforator-related infarction.