Gao F, Wang J, Chen J, et al. - In this retrospective non-comparative case series, researchers sought to examine the etiologies and the clinical features of angle-closure glaucoma (ACG) patients younger than 40 years old in Chinese. Inpatients with the diagnosis of ACG and diagnosed age younger than or equal to 40 years old, who were admitted to Eye, Ear, Nose, and Throat Hospital Fudan University between 2002 and 2017, were included. In total, 298 patients (463 eyes) met the criteria, including 153 females (51.3%) and 145 males (48.7%); the mean age was 25.6 ± 13.0 years. The top three etiologies in study participants were primary angle-closure glaucoma, uveitis, and anterior segment dysgenesis, accounting for 32.6%, 20.3%, and 15.1% of the total patients, respectively. Iridocorneal endothelial syndrome, neovascular glaucoma, nanophthalmos, retinitis pigmentosa, spherophakia, bestrophinopathy, persistent fetal vasculature, iridociliary cysts, congenital retinoschisis, Marfan’s syndrome, retinopathy of prematurity, familial exudative vitreoretinopathy, congenital retinal folds, Coat’s disease, and neurofibromatosis are some of the other known etiologies. Since most etiologies can be pinpointed, a more careful and thorough examination is required for early detection and proper treatment of young ACG patients.