LAUSR

OBJECTIVE Extradural subtemporal keyhole approach could provide adequate removal for some specific middle skull base tumors. The combination of endoscopy and keyhole technique might further help to minimize the complications and provide optimal surgical visualization. Here, a series of attempts with endoscopy by mini-invasive subtemporal extradural approach for five middle skull base tumors were successfully achieved. METHODS From November 2015 to November 2018, resections of five cases of middle cranial fossa tumors were performed with pure endoscopy via subtemporal extradural keyhole approach. Their medical records, imaging data, surgical procedures, pathology results, and follow-up outcomes were collected and analyzed. RESULTS Adequate extradural subtemporal space was successfully established for endoscopy, and tumor resection was performed. Postoperative pathology confirmed cholesteatoma, cholesterol granuloma, schwannoma, granuloma, and osteoblastoma, respectively. Two patients with osteoblastoma and granuloma got subtotal resection, and other three achieved total resection. One patient suffered from brain edema and got relieved after systematic mannitol treatment. No other complications were observed, and no progression was found during follow-up. CONCLUSIONS This exploratory series demonstrated the safety and effectiveness of pure endoscopic surgery via subtemporal extradural route for satisfactory middle cranial base tumor resection.