Although the bifrontal approach used to be recommended for large olfactory groove meningioma (OGM), recent studies showed that large OGMs can also be resected safely via unilateral approaches. The present study aimed to discuss reasons for preferring a unilateral frontotemporal approach (UFTA), and the technical nuances and results of the UFTA, based on 18 cases.

The clinical and surgical data of patients who had been operated on for large (4–6cm) or giant (>6cm) OGM via a UFTA between 2011 and 2018 were retrospectively collected.

In all, 18 patients were included. All tumors were compatible with a diagnosis of OGM in the light of peri-operative examinations. 11 cases (61%) were large and 7 (39%) giant OGM; mean diameter was 6.1cm (range, 4-10cm). Resection extent was Simpson grade II in 14 cases (78%), grade III in 1 (5%), and grade IV in 3 (17%). Sixteen cases (89%) had no peri-operative complications, while 2 patients (11%) showed cerebrospinal fluid leakage and hemorrhagic deposition in the surgical area. There were no new neurological deficits nor deaths.

The UFTA for OGM is a relatively safe and effective approach, ensuring a high total removal rate with low mortality and morbidity. This study, with a reasonable number of patients, is one of the few in the literature on the outcome of this approach.