Olfactory Groove Meningioma Recurrence after Endonasal Endoscopic Surgery: Case Report and Updated Literature Review

Objective: To review the management of olfactory groove meningiomas, review the outcomes in the recent literature comparing endoscopic endonasal with traditional transcranial approaches.

Methods: We present a case of recurrent olfactory groove meningioma following an endonasal endoscopic resection which was re-resected using a supraorbital approach. A PubMed search of the recent literature (2011–2016) was done to look at the outcome following endoscopic and transcranial approaches. The extent of resection, visual outcome, post-operative complications and recurrence rates were analyzed using percentages and proportions, the Fischer exact test and the Student’s t-test.

Results: There were 444 patients in the TCA group with a mean diameter of 4.61 (±1.17) cm and 101 patients in the EEA group with a mean diameter of 3.55 (±0.58) cm (p = 0.0589). GTR was achieved in 90.9% (404/444) in the TCA group and 70.2% (71/101) in the EEA group (p < 0.0001). Of the patients with pre-operative visual disturbances, 80.7% (21/26) of patients in the EEA cohort had an improvement in vision compared with 15.5%(29/186) in the TCA group (p < 0.0001). Olfaction was lost in 61% of TCA and presumably in 100% of EEA patients. CSF leaks and meningitis occurred in 25.7% and 4.95% of EEA patients and 6.3% and 1.12% of TCA patients respectively (p < 0.0001; p = 0.023).

Conclusions: Our updated literature review demonstrates that despite more experience with resection and skull base reconstruction, the literature still supports TCA over EEA with respect to extent of resection and complications. However, patients with predominantly visual symptoms and appropriately sized and located tumors may be considered for EEA as this approach appears to provide higher rates of visual improvement, as long as anosmia is an acceptable consequence.