Surgical nuances of the expanded endoscopic anterior skull base craniectomy for hyperostotic meningioma resection

Background: The rostral expanded endoscopic approach (EEA) to anterior cranial fossa (ACF) has several advantages over transcranial/craniofacial surgery, providing early access to the vascular supply of tumors and reducing morbidities of craniotomy especially that of brain retraction. This article presents endoscopic landmarks and nuances for a wide ACF corridor, with stepwise image-guided dissections highlighting surgical tricks and techniques to enhance surgical safety. Methods: We describe an expanded endoscopic endonasal anterior skull base craniectomy for a recurrent large olfactory groove hyperostotic meningioma, with correlated cadaveric dissections. Conclusion: The widening of rostral EEA can provide a safe and feasible route to access ACF. This article highlights the specific landmarks in endoscopic anatomy with reference to the angle of visualization and bayonetted instruments.