Modified endoscopic transnasal orbital apex decompression in dysthyroid optic neuropathy

Background:To describe the surgical technique and assess the clinical efficacy and safety of modified endoscopic transnasal orbital apex decompression in the treatment of dysthyroid optic neuropathy.Methods:In this retrospective research,forty-two subjects(74 orbits)who underwent modified endoscopic transnasal orbital apex decompression for the treatment of dysthyroid optic neuropathy were enrolled.Preoperative and postoperative best-corrected visual acuity(BCVA),visual field mean deviation(MD),Hertel exophthalmometry,and new onset diplopia were assessed before and after the intervention.The Wilcoxon test was used for differential analysis.Linear mixed-models’analyses were conducted to assess the potential predictors for BCVA change.Results:Postoperatively,the mean BCVA improved from 0.70±0.62 logMAR to 0.22±0.33 logMAR.BCVA significantly improved in 69 eyes(93%),remained stable in 4 eyes(5%)and deteriorated in 1 eye(1%).MD of visual fields improved from−13.73±9.22 dB to−7.23±7.04 dB.Proptosis decreased from 19.57±3.38mm to 16.35±3.01mm.Preoperative BCVA,MD of visual fields and medical rectus diameter were independent factors associated with improvements in BCVA(P<0.05)by linear mixed-models’analyses.Eighteen patients(42.9%)developed new diplopia postoperatively.Conclusion:Modified endoscopic transnasal orbital apex decompression effectively restores vision in dysthyroid optic neuropathy.