Clinical Evaluation of Unilateral Open-Angle Glaucoma: A Two-Year Follow-Up Study

To evaluate the clinical characteristics of unilateral open-angle glaucoma, patients diagnosed with unilateral open-angle glaucoma from January 2017 to October 2018 were divided into primary open-angle glaucoma and normal-tension glaucoma groups according to the type of glaucoma diagnosed. The glaucoma and the contralateral eyes were compared, and the contralateral eye was analyzed for conversion to glaucoma and its risk factors were assessed during the 2-year follow-up period. Among 99 patients, 36 were diagnosed with primary open-angle glaucoma and 63 with normal-tension glaucoma. When comparing the glaucoma eye with the contralateral eye, the visual field mean deviation value (all p<0.001), peripapillary retinal nerve fiber layer thickness (all p<0.001), macular ganglion cell layer-inner plexiform layer thickness (p<0.001, p=0.003), and optic nerve cup-disc ratio (p=0.005, p<0.001) were significantly different in both the primary open-angle glaucoma and normal-tension glaucoma groups. In normal-tension glaucoma, peripapillary retinal nerve fiber layer thickness was significantly thinner in the glaucoma conversion group than in the glaucoma non-conversion group (p=0.008). It was significantly associated with glaucoma conversion (odds ratio=0.97, p=0.023). In conclusion, in patients with unilateral open-angle glaucoma, the contralateral eye may develop glaucoma. In particular, if the peripapillary retinal nerve fiber layer thickness is decreased in normal-tension glaucoma, the possibility of glaucoma conversion is high; hence, careful examination is required.