Unilateral Tailored Fronto-Orbital Approach for Giant Olfactory Groove Meningiomas: Technical Nuances

Abstract

Giant olfactory groove meningiomas (maximum diameter ≥6 cm) remain a surgical challenge. Historically, extensive anterior and antero-lateral approaches have been the primary approaches for removal of such large tumors with limitations and morbidity pertaining to each approach. Herein, the authors describe a minimally invasive, unilateral, tailored fronto-orbital approach for resection of these complex lesions with an emphasis on preservation of the anterior cerebral arteries and olfactory nerves. A 4-stage approach using neuronavigation is performed: 1) predefined corridor, 2) identification of the ipsilateral anterior cerebral artery, 3) postdefined corridor, and 4) tumor base. The details of this approach are described below in a stepwise fashion and supplemented by a sample of 3 cases utilizing this technique. In the 3 representative cases in which this technique was used, gross total resection was achieved without injury to any of the adjacent neurovascular structures. Significant sellar extension can be resected through a second stage endoscopic endonasal approach. Giant olfactory groove meningiomas (≥6 cm) can be safely and completely resected with this 4-stage, unilateral fronto-orbital technique. Furthermore, early identification and preservation of the adjacent critical neurovascular structures can be achieved. This technique avoids the inherent limitations and morbidity associated with the more classic pterional and bifrontal approaches respectively while minimizing normal tissue disruption.