Olfactory Groove Meningiomas from Neurosurgical and Ear, Nose, and Throat Perspectives: Approaches, Techniques, and Outcomes

Abstract

To review the surgical approaches, techniques, outcomes, and recurrence rates in a series of 80 olfactory groove meningioma (OGM) patients operated on between 1990 and 2003. Eighty patients underwent 81 OGM surgeries. Tumor diameter varied from 2 to 9 cm (average, 4.6 cm). In 35 surgeries (43.2%), the tumor was removed through bifrontal craniotomy; nine operations (11.1%) were performed through a unilateral subfrontal approach; 18 surgeries (22.2%) were performed through a pterional approach; seven surgeries (8.6%) were carried out using a fronto-orbital craniotomy; and 12 procedures (14.8%) were accomplished via a subcranial approach. Nine patients (11.3%) had undergone surgery previously and had recurrent tumor. Total removal was obtained in 72 patients (90.0%); subtotal removal was achieved in 8 patients (10.0%). Two patients, one with total and one with subtotal removal, had atypical (World Health Organization Grade II) meningiomas, whereas 78 patients had World Health Organization Grade I tumors. There was no operative mortality and no new permanent focal neurological deficit besides anosmia. Twenty-five patients (31.3%) experienced surgery-related complications. There were no recurrences in 75 patients (93.8%) 6 to 164 months (mean, 70.8 mo) after surgery. Three patients (3.8%) were lost to follow-up. In two patients (2.5%) with subtotal removal, the residual evidenced growth on computed tomography and/or magnetic resonance imaging 1 year after surgery. One of them had an atypical meningioma. The second, a multiple meningiomata patient, was operated on twice in this series. A variety of surgical approaches are used for OGM resection. An approach tailored to the tumor's size, location, and extension, combined with modern microsurgical cranial base techniques, allows full OGM removal with minimal permanent morbidity, excellent neurological outcome, and very low recurrence rates.