Extended Unilateral Frontal Approach for Large Anterior Skull Base Meningiomas: Better Chance of Olfaction Preservation without Compromising the Resection

Introduction: Large anterior cranial fossa meningiomas, especially the midline ones are commonly approached through the extended bifrontal craniotomy. This approach minimizes brain retraction, but it is difficult to preserve olfaction. Furthermore, it necessitates transection of anterior tip of superior sagittal sinus (SSS) and its reflection, which has its own problems. A unilateral extended frontal approach would minimize brain handling without the need for SSS transection and may provide better olfaction preservation.

Methods: Twenty patients with anterior cranial fossa meningioma were operated through this skull base approach. The clinical presentation, radiological studies, intraoperative findings, and outcome at follow-up were recorded. The ethmoidal arteries on one side were coagulated to devascularize the tumor followed by its debulking. The contralateral portion was accessed by undercutting the falx.

Results: Gross total tumor resection could be achieved in 18 out of 20 patients. None of them require transection of SSS. At least one of the olfactory tracts could be anatomically preserved in all patients. Functional olfaction preservation was achieved in 12 patients. No patient developed new-onset anosmia.

Conclusion: The extended unilateral frontal approach provides a good corridor to resect large midline anterior cranial fossa meningiomas with avoidance of SSS ligation and better olfaction preservation without significant brain handling.