title: Undercorrection of myopia enhances rather than inhibits myopia progression.
abstract: The effect of myopic defocus on myopia progression was assessed in a two-year prospective study on 94 myopes aged 9-14 years, randomly allocated to an undercorrected group or a fully corrected control group. The 47 experimental subjects were blurred by approximately +0.75 D (blurring VA to 6/12), while the controls were fully corrected. Undercorrection produced more rapid myopia progression and axial elongation (ANOVA, F(1,374)=14.32, p<0.01). Contrary to animal studies, myopic defocus speeds up myopia development in already myopic humans. Myopia could be caused by a failure to detect the direction of defocus rather than by a mechanism exhibiting a zero-point error.
authors.affiliation: Department of Optometry, National University of Malaysia, 50300, Kuala Lumpur, Malaysia.
authors.forename: Kahmeng
authors.initials: K
authors.lastname: Chung
authors.forename: Norhani
authors.initials: N
authors.lastname: Mohidin
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: O'Leary
mesh_terms: D000293:Adolescent; D000704:Analysis of Variance; D002648:Child; D018450:Disease Progression; D005139:Eyeglasses; D005260:Female; D006801:Humans; D008297:Male; D009216:Myopia / Q000209:etiology / Q000503:physiopathology / Q000628:therapy*; D010349:Patient Compliance; D014792:Visual Acuity