Visual Outcomes after Expanded Endoscopic Endonasal Resection of Anterior Skull Base Meningiomas

Background: The endoscopic endonasal approach has become increasingly utilized in the treatment of anterior skull base meningiomas. These tumors, in particularly planum and tuberculum meningiomas, often cause visual symptoms due to compression of the optic apparatus, and/or involvement of optic canal. We aimed to examine visual outcomes after endoscopic endonasal resection of anterior skull base meningiomas in patients who also underwent optic decompression, and to identify preoperative factors predictive of postoperative visual improvement.

Methods: We performed a retrospective chart review on 21 patients who underwent endoscopic endonasal resection of anterior skull base meningiomas with optic nerve decompression between January 1, 2005, and September 1, 2018, at McMaster University.

Results: The mean age of our patients was 57.6 years. This comprised 4 male and 17 female patients. Seventeen patients (80.9%) presented with visual symptoms. The mean duration of symptoms was 8.96 months. Gross-total resection was achieved in five patients (23.8%). Four additional patients (19%) underwent a second-stage transcranial surgery to achieve gross-total resection. Three other patients received radiation therapy.

Bilateral decompression of optic apparatus was performed in 10 patients, and unilateral decompression was performed in 11 patients. Six patients (35.3%) had postoperative improvement of visual acuity of at least two lines on Snellen chart. Three patients had improvement of visual fields. Visual deterioration occurred in one patient (4.76%).

On comparing preoperative symptom duration, less than 6 months of visual decline was more likely to be associated with postoperative improvement of visual acuity, with an odds ratio (OR) of 0.0625 (95% CI: 0.0043–0.915, p < 0.05). Tumor volume of less than 30 mL was not associated with better visual outcomes in our cohort (OR: 1.17; 95% CI: 0.133–10.22; p = 0.14).

Conclusion: The endoscopic endonasal approach combined with optic nerve decompression can achieve good visual outcomes in patients with anterior skull base meningiomas. Symptom duration of less than 6 months is a positive predictor of postoperative visual acuity improvement.