Kim JS, et al. - Researchers performed this retrospective observational cohort study to examine clinical features and risk factors for glaucoma conversion of the contralateral eye in unilateral normal-tension glaucoma (NTG) patients. The sample consisted of 76 patients who had been diagnosed with unilateral NTG at the baseline and followed up for more than 5 years. Twenty-one of 79 (26.6%) patients were confirmed to have developed glaucoma in the non-glaucomatous contralateral eye during the mean follow-up period of 7.3 ± 2.4 years. Data reported that the 5-year rate of glaucoma conversion in contralateral eyes was 19.7%. Among patients with unilateral NTG, those with low central corneal thickness and a high maximum width of β-zone parapapillary atrophy-disc diameter ratio as well as high intraocular pressure in the contralateral eye are more prone to develop glaucoma in that eye during long-term follow-up.