title: A longitudinal study on the relationship between myopia development and near accommodation lag in myopic children.
abstract: OBJECTIVE
  To investigate the possible relationship between myopia progression and near accommodative lag.
  
  
  METHODS
  A 1-year longitudinal study was carried out to measure the accommodative response and myopia progression in 62 children with mild and progressing myopia at two visits: they were 10.81 +/- 1.60 years old with refractive error -1.70 +/- 0.76 D on entry. Repeated measurements included refractive error, ocular biometry and accommodative response at 33 cm. The refractive error was determined by autorefraction after cycloplegia; ocular biometry by A-scan ultrasonography; and accommodative response by an open-field autorefractor. Results were based on the right eye and analysed by paired t-test and Pearson's correlation coefficient.
  
  
  RESULTS
  Myopia progression in the year was -0.72 +/- 0.37 D (p < 0.001) with a range from -0.06 to -1.96 D. The change of axial length and vitreous depth were 0.41 +/- 0.25 mm (p < 0.001) and 0.36 +/- 0.24 mm (p < 0.001), respectively. The near lag was 0.76 +/- 0.29 D on entry and 0.72 +/- 0.38 D 1 year later (p = 0.79). No statistically significant correlations were found between near lag vs myopia progression and the change of ocular biometry as a whole (p > 0.10 for all). There was no significant difference in myopia progression between myopic children with greater than, compared to less than the mean amount of near lag (p = 0.36).
  
  
  CONCLUSIONS
  This study demonstrates no statistically significant relationship between myopia progression and near accommodation lag in children with mild and progressing myopia. There is no evidence that near lag provides a stimulus to progression in this stage of myopia.
authors.affiliation: State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China.
authors.forename: Lan
authors.initials: L
authors.lastname: Weizhong
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhikuan
authors.forename: Liu
authors.initials: L
authors.lastname: Wen
authors.forename: Chen
authors.initials: C
authors.lastname: Xiang
authors.forename: Ge
authors.initials: G
authors.lastname: Jian
mesh_terms: D000065:Accommodation, Ocular / Q000502:physiology*; D000293:Adolescent; D002648:Child; D018450:Disease Progression; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D008297:Male; D009216:Myopia / Q000503:physiopathology*