A 2-Year Longitudinal Study of Myopia Progression and Optical Component Changes among Hong Kong Schoolchildren

• Published in: Optometry and vision science Vol. 76; no. 6; pp. 370 - 380
• Main Authors: SIU YIN LAM, CARLY, EDWARDS, MARION, MILLODOT, MICHEL, HAN GOH, WINNIE SHUK
• Format: Journal Article
• Language: English
• Published: United States 01.06.1999
• Subjects: Adolescent; Age Factors; Child; Cornea - physiopathology; Disease Progression; Eye - physiopathology; Female; Follow-Up Studies; Hong Kong - epidemiology; Humans; Incidence; Light refraction; Male; Myopia - epidemiology; Myopia - pathology; Myopia - physiopathology; Ophthalmology; Pediatrics; Prevalence; Refraction, Ocular; Retrospective Studies; Sex Factors; Vitreous Body - physiopathology; Hong Kong
• ISSN: 1040-5488
• DOI: 10.1097/00006324-199906000-00016

This study investigated refractive error and optical component changes in a group of 142 Hong Kong schoolchildren from age 6 to 17 years over a 2-year period between 1991 and 1993. Subjects were refracted subjectively and corneal curvatures and ocular dimensions were measured. At the end of the 2-year study, the mean spherical equivalent refraction (SER) was -1.86 D (SD 1.99 D) and 62% of the schoolchildren were myopic. The annual incidence of myopia was 11.8%. Children aged 10 years and under had a greater change in SER toward myopia than older children. The annual rate of myopia progression for the myopic children was -0.46 D (SD 0.40 D) and the rate of progression was greatest between age 6 and 10 years old. Vitreous depth/axial length elongation was the main component contributing to the progression of myopia. Hong Kong schoolchildren develop myopia as early as 6 years old and myopia progresses at a greater rate compared with children of European extraction.