title: Dynamic changes of ocular biometric parameters: a modified form-deprivation myopia model of young guinea pigs.
abstract: OBJECTIVE
  To evaluate the dynamic ocular biometric changes of a modified form-deprivation myopia model in young guinea pigs.
  
  
  METHODS
  THE ANIMALS WERE RANDOMLY ASSIGNED TO TWO GROUPS: the monocularly deprived facemask group (MDF, with all the right eyes covered, n=24) and the normal control group (free of facemask, n=24). Each group was then equally divided into four subgroups which were followed up for 2, 4, 6 and 8 weeks, respectively. Parameters measured from every eye included refraction, corneal curvature, axial length and the dry weight of sclera at the posterior pole.
  
  
  RESULTS
  All the facemasks remained in place during the follow-up. The covered eyes developed myopia with the vitreous chamber lengthening and the dry weight of posterior sclera reduced at each time point compared with the contralateral uncovered (P<0.05 at all time points). The changes had a linear correlation with the deprivation time (P<0.05). There were no significant differences in all the parameters between the uncovered eyes of MDF group and the normal control group (P>0.05 at all time points).
  
  
  CONCLUSIONS
  Monocular form deprivation with the facemask is highly effective and non-invasive in inducing axial myopia in guinea pigs. The axial myopia is mainly caused by the increased vitreous chamber length and the weakened posterior sclera rigidity. The form-deprivation eye didn't interfere with the natural development of the contralateral eye.
authors.affiliation: Department of Ophthalmology, Zhejiang Provincial People's Hospital, Hangzhou 310014, Zhejiang Province, China.
authors.forename: Hai-Lan
authors.initials: HL
authors.lastname: Zhao
authors.forename: Rui-Qin
authors.initials: RQ
authors.lastname: Wang
authors.forename: Miao-Qin
authors.initials: MQ
authors.lastname: Wu
authors.forename: Jin
authors.initials: J
authors.lastname: Jiang