Modified Far Lateral Approach for Posterior Circulation Aneurysm. An Institutional Experience

Introduction: The modified far-lateral approach is a modified version of the lateral sub occipital approach without drilling of the condyle. This approach can be used for accessing lesions anterior and anterolateral to the brainstem and craniovertebral junction.

Objective: In our study, we described the surgical outcomes and complications of the modified far-lateral approach for posterior circulation aneurysm.

Methods: From 1994 to 2014, a total of 22 patients underwent surgery using the modified far-lateral approach. We retrospectively reviewed the records of these patients to analyze their clinical outcomes.

Results: Mean age was 53 years (range 30–76) 0.14 patients were female and 8 cases male. Most common presenting symptoms were sudden onset headache (83%), followed by loss of consciousness (56%). Eighteen (81%) patients had saccular aneurysms whereas four (18%) had fusiform aneurysms. Twelve patients with PICA aneurysms, four patient with basilar aneurysms, four with a vertebral artery aneurysms and one each for vertebra-basilar junction and AICA aneurysm were approached by a modified far-lateral approach. All aneurysm were clipped successfully. Follow-up data was available for 22 patients (mean duration= 68 months). At last follow-up, 18 patients had good recovery (GOS 5) and 4 patients had a moderate disability (GOS 4). One patient each developed lower cranial nerve palsy and bilateral sixth nerve palsy.

Conclusion: Modified far-lateral approach without condyle resection and vertebral artery mobilization are associated with low procedure related morbidity and comparable outcomes to the classically described more extensive approach.