The present study investigates the seasonal variations of acute angle-closure glaucoma in patients visiting the hospital.

Eighty-seven patients (94 eyes) who underwent laser iridotomy were retrospectively analyzed over 5 years. Monthly and seasonal variations were investigated and the difference in seasonal variations according to sex, age, and inhabited area were inspected.

When evaluating monthly variations, acute angle-closure glaucoma occurred mostly in January (13.8%). Incidence of glaucoma was the highest in winter (29.9%), decreased in spring and summer (26.4%) and was lowest in autumn (17.2%). In big cities, the incidence trend was highest in spring (31.8%), lowest in autumn (19.7%) and slightly elevated in winter (27.3%). However, in small cities and rural areas, the incidence was highest in summer (42.9%) and winter (38.1%). There were significant differences between inhabited areas.

Among the patients, seasonal incidence of acute angle-closure glaucoma was the highest in winter and decreased as autumn approached. There were differences of incidence between inhabited areas.