[The correlations between distance stereoacuity and levels of control at different far distances in children with intermittent exotropia].

Abstract

Objective: To study the correlations between the distance stereoacuity and the levels of control at different far distance fixations in children with intermittent exotropia. Methods: In this prospective, non-interventional case series study, 52 children with intermittent exotropia (basic, divergence excess and pseudo-divergence excess types, exodeviation angles≥15 PD) admitted to the Shandong Provincial Hospital Affiliated to Shandong University for surgery between August 2014 and March 2015 were enrolled. The distance stereoacuity was tested with the distance Randot stereotest, and the control of exodeviation was assessed at outdoor far distance fixation of 50 m, indoor far distance fixation of 30 m, and indoor distance fixation of 3 m, respectively, using the office-based 6-point control scale proposed by Mohney and Holmes. The distance stereoacuity and control scores of every intermittent exotropia child were tested 3-4 times in a single day with an interval of at least 2 hours. Nonparametric Spearman rank method was used to analyze the correlations between distance stereoacuity and levels of control at three different far distances in children with intermittent exotropia. Results: The mean age of 52 enrolled children (26 males, 26 females) was 7 years (range, 5-12 years), and 192 groups of distance stereoacuity and control scores were got for the 52 children. Positive correlations between the distance stereoacuity and the levels of control at outdoor far distance fixation of 50 m, indoor far distance fixation of 30 m, and indoor distance fixation of 3 m were observed (coefficients of correlations; r=0.489, 0.472, 0.282, all P<0.001). Conclusion: There are correlations between the distance stereoacuity and the levels of control at outdoor far distance fixation of 50 m, indoor far distance fixation of 30 m and indoor distance fixation of 3 m in children with intermittent exotropia, and the former two are found to be stronger than the latter one. (Chin J Ophthalmol, 2019, 55:25-30).