Endonasal Endoscopic Optic Canal Decompression for Nontraumatic Optic Neuropathy: Long-Term Visual Outcomes in 36 Patients.

BACKGROUND:The management of compressive optic neuropathy (CON) arising from nontraumatic compression of the optic nerve within the optic canal (OC) remains a topic of controversy. In this study, our aim was to assess the effectiveness and safety of endonasal endoscopic optic nerve decompression (EEOND). In addition, we conducted an analysis of prognostic factors that could potentially influence visual outcomes. METHODS:This retrospective cohort study was conducted between January 2015 and December 2021, involving adult patients (age > 18) diagnosed with CON and treated with EEOND at our specialized skull base expert center. The study evaluated the impact of surgery on visual acuity (VA), mean deficit (MD), and foveal threshold (FT) of the visual field (VF). These parameters were assessed preoperatively and at 3- and 12-month postoperative follow-ups. The relationship between clinical variables and the differences in postoperative to preoperative VA, MD, and FT of the visual field was analyzed through univariate and multivariate approaches. RESULTS:Thirty-six patients (38 eyes) were included, with a mean age of 52 (±12) years, and a female predominance (78%). The mean ophthalmologic follow-up duration was 38 (±32) months. At the 12-month follow-up, 39% of the patients exhibited a VA improvement of ≥0.2 LogMAR. Partial VF improvement (MD improvement ≥25%) was observed in 55% of the patients, whereas 19% experienced complete recovery. In multivariate analysis, the presence of a type 4 OC was identified as the sole negative prognostic factor for visual improvement (VA and VF) at 12 months. Six patients (17%) encountered minor surgical complications, all of which were managed conservatively and had no impact on visual outcomes. CONCLUSIONS:Our study demonstrates that EEOND is a safe and effective procedure, even in cases of severe and long-lasting CON caused by nontraumatic compression of the optic nerve at the level of the OC.