A Modern Approach to Olfactory Groove Meningiomas

Objective: Management of OGM has changed significantly with the advances in extended endonasal approaches (EEA), which is an excellent approach for patients with anosmia since allows early devascularization and minimizes retraction on the frontal lobes. Resection can be performed by both EEA and/or open techniques based on the tumor size and patient’s preoperative olfaction status. Early devascularization, debulking, and detachment of the tumor from surrounding brain make transcribriform EEA an attractive strategy for OGM. However, nearly guaranteed postoperative anosmia and inability to reach tumor extending laterally beyond the optic nerves limit the approach. Craniotomy, on the other hand, is best suited for preservation of olfaction and is effective in reaching tumors that extend outside the reach of EEA. However, often times, these slow-growing tumors present late and are quite large. A solely transcranial approach would require significant manipulation and retraction of the frontal lobes. These OGM may best be treated by a staged EEA–craniotomy approach. The goal of this study was to present the algorithm developed at our institution for the management of OGM and to evaluate its effectiveness in our series of patients treated with the algorithm.

Methods: The authors conducted an IRB-approved, nonrandomized historic cohort including all consecutive cases of OGM treated surgically between 2010 and 2020. Patient demographic information, presenting symptoms, operative details and complications data were collected. Pre- and postoperative tumor and T2/FLAIR volumes were calculated via Visage Imaging software ([Fig. 1]).

Fig. 1

Results: Thirty-one patients were treated with OGM (14 craniotomy only, 11 EEA only, and 6 staged). There was a significant difference in distribution of patients presenting with anosmia and visual disturbance by approach. Tumor size was significantly correlated with preoperative vasogenic edema. Gross total resection was achieved in 90% of cases, with near-total resection occurring twice with EEA and once with a staged approach. T2/FLAIR hyperintensity completely resolved in 90% of cases and rates did not differ by approach. Rates of complication were not significantly different by approach, including 4 total CSF leaks (p = 0.68) ([Fig. 2]).

Fig. 2

Conclusion: A staged approach for management of large OGM with anosmia and significant lateral extension is a safe and effective option for surgical management. Through utilization of our described algorithm, we achieved a high rate of GTR, and this strategy may be considered for large olfactory groove meningiomas.

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Artikel online veröffentlicht:
05. Februar 2024