Nearwork-induced transient myopia in preadolescent Hong Kong Chinese

Wolffsohn, James S., Gilmartin, Bernard, Li, Roger Wing-hong, Hastings Edwards, Marion, Chat, Sandy Wing-shan, Lew, John Kwok-fai and Yu, Bibianna Sin-ying (2003). Nearwork-induced transient myopia in preadolescent Hong Kong Chinese. Investigative Ophthalmology and Visual Science, 44 (5), pp. 2284-2289.

Abstract

PURPOSE. To compare the magnitude and time course of nearwork-induced transient myopia (NITM) in preadolescent Hong Kong Chinese myopes and emmetropes. METHOD. Forty-five Hong Kong Chinese children, 35 myopes and 10 emmetropes aged 6 to 12 years (median, 7.5), monocularly viewed a letter target through a Badal lens for 5 minutes at either 5.00- or 2.50-D accommodative demand, followed by 3 minutes of viewing the equivalent target at optical infinity. Accommodative responses were measured continuously with a modified, infrared, objective open-field autorefractor. Accommodative responses were also measured for a countercondition: viewing of a letter target for 5 minutes at optical infinity, followed by 3 minutes of viewing the target at a 5.00-D accommodative demand. The results were compared with tonic accommodation and both subject and family history of refractive error. RESULTS. Retinal-blur-driven NITM was significantly greater in Hong Kong Chinese children with myopic vision than in the emmetropes after both near tasks, but showed no significant dose effect. The NITM was still evident 3 minutes after viewing the 5.00-D near task for 5 minutes. The magnitude of NITM correlated with the accommodative drift after viewing a distant target for more than 4 minutes, but was unrelated to the subjects' or family history of refractive error. CONCLUSIONS. In a preadolescent ethnic population with known predisposition to myopia, there is a significant posttask blur-driven accommodative NITM, which is sustained for longer than has previously been found in white adults.

Publication DOI: https://doi.org/10.1167/iovs.02-0373
Divisions: Life & Health Sciences > Optometry
Life & Health Sciences > Ophthalmic Research Group
Life & Health Sciences
Uncontrolled Keywords: transient myopia,Hong Kong,retinal-blur-driven,Ophthalmology
Full Text Link: http://www.iovs ... ntent/44/5/2284
Related URLs: http://www.scop ... tnerID=8YFLogxK (Scopus URL)
Published Date: 2003-05
Authors: Wolffsohn, James S. ( 0000-0003-4673-8927)
Gilmartin, Bernard
Li, Roger Wing-hong
Hastings Edwards, Marion
Chat, Sandy Wing-shan
Lew, John Kwok-fai
Yu, Bibianna Sin-ying

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