Quantitative Analysis of Optic Canal Superior Wall Decompression in Endoscopic Endonasal Resection of Tuberculum Sellae Meningiomas.

BACKGROUND AND OBJECTIVES:To describe technical nuances of optic canal superior wall (OCSW) decompression during the endoscopic endonasal approach (EEA) for tuberculum sellae meningiomas (TSMs), quantify decompression, and evaluate associations with tumor features and outcomes. METHODS:Data of 17 patients who underwent EEA for TSMs were retrospectively reviewed. Postoperative computed tomography was performed to measure the width and anteroposterior length of the OCSW decompression, and an OCSW decompression rate was calculated relative to the interanterior clinoid process distance. Tumor characteristics were scored using the University of California-San Francisco (UCSF) system, and surgical outcomes were assessed based on the extent of resection, postoperative complications, cerebrospinal fluid leakage, Visual Impairment Score (VIS)-based visual change, and intraoperative blood loss. Correlations and a two-predictor logistic regression (tumor size, OCSW decompression) modeled visual improvement. RESULTS:The cohort comprised 11 female and 6 male patients (mean age, 64.6 years). The mean UCSF total score was 4.65 (median, 5; range, 1-6), with mean subscores of 1.71 (size), 1.35 (canal), and 1.59 (arterial encasement). Gross total resection was achieved in 12/17 (70.6%), and VIS improved in 13/17 (76.5%); no visual deterioration occurred. The mean OCSW opening ratio was 93.3% (range, 71.4%-107.8%). OCSW decompression correlated with tumor size score (Spearman ρ = 0.55, P = .022) and total UCSF score (ρ = 0.56, P = .019), but not with extent of resection, cerebrospinal fluid leakage, VIS improvement on univariate testing, or blood loss. In the logistic model, tumor size (odds ratio 2.42, P = .0038) and OCSW decompression (odds ratio 2.04, P = .0092) independently predicted visual improvement (pseudo-R2 = 0.49; goodness-of-fit P = .798). CONCLUSION:Wider OCSW decompression scaled with tumor complexity and, after adjustment for tumor size, independently increased the odds of visual improvement. These data support planned, adequately wide OCSW decompression to secure lateral working space and facilitate safe dissection in EEA for TSMs.