title: Intraocular Pressure Changes during Accommodation in Progressing Myopes, Stable Myopes and Emmetropes.
abstract: OBJECTIVE
  To investigate the changes of intraocular pressure (IOP) induced by 3-diopter (3 D) accommodation in progressing myopes, stable myopes and emmetropes.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  318 subjects including 270 myopes and 48 emmetropes.
  
  
  METHODS
  195 progressing myopes, 75 stable myopes and 48 emmetropes participated in this study. All subjects had their IOP measured using iCare rebound tonometer while accommodative stimuli of 0 D and 3 D were presented.
  
  
  METHODS
  IOP values without accommodation and with 3 D accommodation were measured in all subjects. Baseline IOPs and IOP changes were compared within and between groups.
  
  
  RESULTS
  There was no significant difference in IOPs between progressing myopes, stable myopes and emmetropes when no accommodation was induced (17.47±3.46, 16.62±2.98 and 16.80±3.62 respectively, p>0.05). IOP experienced an insignificantly slight decrease after 3 D accommodation in three groups (mean change -0.19±2.16, -0.03±1.68 and -0.39±2.65 respectively, p>0.05). Subgroup analysis showed in progressing myopic group, IOP of children (<18 years old) declined with accommodation while IOP of adults (≥18 years) increased, and the difference was statistically significant (p = 0.008). However, after excluding the age factor, accommodation induced IOP changes of high progressing myopes (≤-6 D), low, moderate and non-myopes (>-6 D) was not significantly different after Bonferroni correction (p = 0.838).
  
  
  CONCLUSIONS
  Although no difference was detected between the baseline IOPs and accommodation induced IOP changes in progressing myopes, stable myopes and emmetropes, this study found accommodation could cause transient IOP elevation in adult progressing myopes.
authors.affiliation: Department of Ophthalmology, Peking University Third Hospital, Beijing, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Ophthalmology, Peking University Third Hospital, Beijing, China.
authors.forename: Huibin
authors.initials: H
authors.lastname: Lv
authors.affiliation: Department of Ophthalmology, Peking University Third Hospital, Beijing, China.
authors.forename: Xiaodan
authors.initials: X
authors.lastname: Jiang
authors.affiliation: Department of Ophthalmology, Peking University Third Hospital, Beijing, China.
authors.forename: Xiaodan
authors.initials: X
authors.lastname: Hu
authors.affiliation: Department of Ophthalmology, Peking University Third Hospital, Beijing, China.
authors.forename: Mingzhou
authors.initials: M
authors.lastname: Zhang
authors.affiliation: Department of Ophthalmology, Peking University Third Hospital, Beijing, China.
authors.forename: Xuemin
authors.initials: X
authors.lastname: Li
mesh_terms: D000065:Accommodation, Ocular; D000293:Adolescent; D058453:Emmetropia; D005260:Female; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D047728:Myopia, Degenerative / Q000503:physiopathology*; D055815:Young Adult