Abstract:ObjectiveTo investigate the anatomic corridors, landmarks and dissection method of the skull base surgery via endoscopic inferolateral orbital wall approach (EILOWA) by cadaveric dissection.Methods5 cadaveric heads (10 sides) were dissected. Stepbystep dissection via EILOWA was performed to identify the anatomic corridors, vital landmarks and boundaries.ResultsThe study defined 5 corridors for EILOWA, including corridors through trigeminal nerve, foramen lacerum, cavernous sinus, petrous and posterior cranial fossa, and middle cranial fossa. The crucial anatomic landmarks and boundaries as well as dissection passage, step and method of each corridor were identified and analyzed.ConclusionsEILOWA provides the surgeon with a direct route to lateral areas of the ventral skull base, and middle cranial fossa, even posterior cranial fossa and partial lateral skull base. In addition, it allows an optimal view of the intracranial and extracranial portions of the maxillary and mandibular nerves. Further anatomic and clinical studies are needed to validate this approach in surgical practice.