Optic Disc Torsion Presenting as Unilateral Glaucomatous-Appearing Visual Field Defect in Young Myopic Korean Eyes

Purpose: To investigate the ocular features of companion eyes in an attempt to find eye-related factors that are associated with unilateral glaucomatous-appearing visual field (VF) defects in young myopic subjects. Design: Retrospective, cross-sectional study. Participants: Thirty-nine patients (age range, 20-50 years) with unilateral glaucomatous-appearing VF defect and myopia. Methods: A comparison was performed between VF-affected eyes and contralateral normal eyes. Optic disc torsion and tilt ratio were measured from disc photographs. Logistic regression analysis and linear regression analysis were performed to investigate various ocular parameters, including torsion degree and tilt ratio, that may be associated with the presence and severity of VF defect. Main Outcome Measures: Torsion degree, tilt ratio, and the severity of VF defect. Results: Optic disc torsion degree (16.63 +/- 9.78 degrees) of VF-affected eyes was statistically greater than that of the normal contralateral eyes (8.69 +/- 7.28 degrees; P < 0.001). Optic disc torsion was more prevalent in VF-affected eyes (66.6%) than in normal contralateral eyes (15.3%; P < 0.001). In the multivariate analysis, the degree of optic disc torsion was associated significantly with the presence of VF defect (P = 0.005). The torsion degree (P = 0.006) and retinal nerve fiber layer thickness (P = 0.004) were associated significantly with the severity of VF defect. Conclusions: The prevalence and degree of optic disc torsion in the VF-affected eyes were significantly greater than those of contralateral normal eyes in unilateral, young, myopic patients with glaucomatous-appearing VF defect. Optic disc torsion should be considered in the presence of unilateral glaucomatous-appearing VF defect in young (C) 2014 by the American Academy of Ophthalmology.