EPIDEMIOLOGIC CHARACTERISTICS OF RHEGMATOGENOUS RETINAL-DETACHMENT INKUMAMOTO, JAPAN

Background: The epidemiology of rhegmatogenous retinal detachment in A sians is not well known. We studied the epidemiologic characteristics of rhegmatogenous retinal detachment in Kumamoto, Japan. Methods: The study was based on a retrospective chart review of hospital patients w ho were treated for primary rhegmatogenous retinal detachment in 1990. The data were collected from seven hospitals in the Kumamoto area. Re sults: From a population of 1 840 000, 192 residents developed retinal detachment. The annual incidence was therefore 10.4 per 100 000 popul ation (9.6 for males, 11.2 for females). The incidences of three types of detachment - nontraumatic phakic, aphakic, and blunt trauma were 9 .8, 0.5, and 0.2 per 100 000 population, respectively. In 109 of 180 p atients (60.6%) with nontraumatic phakic detachment, retinal breaks we re associated with lattice degeneration. In females, 14 of 106 nontrau matic phakic cases (13.2%) were secondary to macular holes. Conclusion : Compared with previously published studies from other countries, the incidence of detachments associated with lattice degeneration and mac ular hole was higher, while the incidences of aphakic detachment and d etachment due to blunt trauma were lower in Japan. Racial factors and living habits may affect the development of retinal detachment.