Improving the Assessment of Visual Outcomes After Resection of Tuberculum Sellae Meningiomas

BACKGROUND AND OBJECTIVES: Tuberculum sellae meningioma (TSM) may be resected transcranially or through the endoscopic endonasal approach (EEA). Despite vision frequently being compromised, the description of visual outcomes across the literature is poor. The authors present a series of patients with TSM managed purely by the EEA and introduce the Visual Field Index (VFI) as a readily available numerical measure of a patient's visual function. METHODS: A retrospective cohort study of patients undergoing endoscopic resection of TSM was conducted. Baseline data were reported as well as routine visual assessment, VFI, and the VFI-delta (the difference between preoperative and postoperative VFI). Correlation between the VFI and visual symptoms was assessed and general outcomes described, including any significant factors predicting visual outcome. RESULTS: Fifty patients met inclusion criteria. The median VFI for incidental (n = 11) and symptomatic (n = 39) lesions was 98% (96.5-99) and 73% (54-83), respectively ( P < .001). Symptomatic TSM were larger and had lower baseline VFI, thinner retinal nerve fiber layer, and lower apparent diffusion coefficient values. Preoperative VFI and VFI-delta both strongly correlated with patient-reported outcomes and visual acuity. 94% of the total cohort had stable/improved postoperative vision, and 68% of symptomatic patients reported better vision after surgery (median VFI-delta 20, IQR 14-36). Visual deterioration occurred in 3 patients (6% of cohort). Lower VFI-delta (i.e., poorer visual outcome) was associated with greater craniocaudal tumor diameter and thinner retinal nerve fiber layer on multivariable linear regression ( P = .01). A simple nomogram to predict VFI-delta was created using the 3 significant predictive variables with satisfactory internal validity. CONCLUSION: Resection of TSM through the EEA results in satisfactory visual outcomes in 94% of patients. The VFI and VFI-delta correlate strongly with traditional assessments of vision and are simple and objective metrics that may improve the analysis of visual outcomes in future research.