The medial transorbital approach in cranioendoscopic skull base tumor resections for locally advanced tumors

Background: Orbital structure preservation and avoidance of facial incisions without compromising oncological outcome are key to maintaining function and quality of life in locally advanced sinonasal tumor surgery. A transorbital approach at our institution has proven invaluable during cranioendoscopic skull base tumor resections and there are few descriptions of this in the literature. Methods: An IRB-approved retrospective chart review was conducted at a tertiary cancer center for patients between 2020 and 2022 undergoing cranioendoscopic tumor resections utilizing a transorbital approach. Data collected included histopathology, sinus origin, disease extent, stage, operative details, length of stay, neoadjuvant treatment and adjuvant treatment. Recurrence, survival, and complication rates were assessed. Results: Four patients were identified for inclusion, including a SMARCB1-deficient carcinoma, esthesioneuroblastoma, squamous cell carcinoma and meningioma. All patients had resection of gross and microscopic disease with preservation of orbital contents. Post-operatively, one patient had mild diplopia on inferior gaze, all other patients had normal vision. Median follow-up was 9.5 months. One patient had recurrence of disease intracranially. Conclusions: The cranioendoscopic approach with a medial transorbital incision has multiple benefits. It avoids the need for a Weber-Ferguson incision with associated facial scar, allows for early intra-operative assessment for orbital invasion using tactile feedback and safe dissection of disease while protecting the globe and rectus muscles. This leads to preservation of eye function while ensuring an oncological resection. Other advantages include ligation of the anterior ethmoid artery and access for reconstruction of the medial orbital wall.