title: Relationship between higher-order aberrations and myopia progression in schoolchildren: a retrospective study.
abstract: OBJECTIVE
  To investigate the relationship between higher-order aberration (HOA) and myopic progression in school children.
  
  
  METHODS
  Between April 23, 2011 and August 29, 2011 in the children's myopia outpatient clinic of the West China Hospital of Sichuan University, 148 eyes of 74 schoolchildren were reviewed. HOAs for a 6-mm pupil were measured with an aberrometer. Myopic progression rate was defined according to the change in spherical equivalent refraction (SER) divided by the time span (years). Subjects with myopic progression rate of ≥0.50 diopters (D) were classified as the 'fast' group and the subjects with myopic progression rate of <0.50D were classified as the 'slow' group. A retrospective study was conducted to compare HOA between the two groups, using root mean square (RMS) values and Zernike coefficients.
  
  
  RESULTS
  The RMS values of HOA (t=2.316, P=0.02), HOA without Z4 (0) (t=2.224, P=0.03), third-order aberrations (t'=2.62, P=0.01), and coma (t'=2.49, P=0.01) were significantly higher in the fast group than those in the slow group. The individual Zernike coefficients of Z3 (-1) (t=-2.072, P=0.04) and Z5 (1) (Z =-2.627, P=0.01) displayed statistically significant differences between the two groups. Significant correlations were found between the RMS values of HOA (r=0.193, P=0.019), RMS values of HOA without Z4 (0) (r=0.23, P =0.005), RMS values of coma (r=0.235, P=0.004), RMS values of third-order aberrations (r=0.243, P =0.003), and the progression rate.
  
  
  CONCLUSIONS
  Our results provide evidence of a relationship between HOA and myopic progression. In a future prospective longitudinal study, we aim to verify whether HOA is a risk factor for myopic progression.
authors.affiliation: Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu 610041, Sichuan Province, China.
authors.forename: Ning
authors.initials: N
authors.lastname: Zhang
authors.forename: Xu-Bo
authors.initials: XB
authors.lastname: Yang
authors.forename: Wen-Qiu
authors.initials: WQ
authors.lastname: Zhang
authors.forename: Long-Qian
authors.initials: LQ
authors.lastname: Liu
authors.forename: Guang-Jing
authors.initials: GJ
authors.lastname: Dong
authors.forename: Tao-Wen
authors.initials: TW
authors.lastname: Chen
authors.forename: Meng
authors.initials: M
authors.lastname: Liao
authors.forename: Xuan
authors.initials: X
authors.lastname: Liao
keywords: aberration; children; disease progression; myopia; refractive errors/etiology