The measurement and analysis of stereopsis on children intermittent exotropia after surgery over one year

Abstract

Objective To explore the long-term therapy effect of children intermittent exotropia after surgery and the impact factors of acquired foveolar stereoscopic vision. Methods A total of 216 children with intermittent exotropia aged 4-15 years were accepted the orthopia surgery. Before the surgery and 1 month or over 1 year after the surgery, position of eye, binocular vision and far and near stereoscopic vision were determined. The averaged years of following up were 3.68. Re- suits One year or longer after the surgery, 90.74% of all the children acquired the near stereoscopic vision less than 60 ＂, while 74.07% acquired the far stereoscopic vision less than 60 ＂. The far and near foveolar stereoscopic visions had no significant difference. According to the age of the pa- tients, they were divided into three groups, including less than 6 years old group, 6-9 years old group and more than 9 years old group. There was no significance in far and near foveolar stereo- scopic visions among the three groups. For a long time after operation, 150 （69.44%） patients were orthotopic, 66 （30.56%） patients were not fully orthotopic. The tested positive of near stereoscopic vi- sion less than 60 ＂ had no significance between orthotopic patients and nor fully orthotopic patients. The tested positive of the far stereoscopic vision less than 60 ＂ in orthotopic patients was 80.00%,while that in nor fully orthotopic patients was 60.61%. The difference of the test positive was signif- icant （x^2=12.17, P 〈0.01）. The logistic analysis showed that the tested positive of the far foveolar ste- reoscopic visions was associated with whether the patients were with far stereoscopic vision before surgery. Orthotopic maintain long-term after surgery was associated with the tested positive of foveo- lar stereoscopic vision. Conclusions The far and near stereoscopic vision are improved after chil- dren intermittent exotropia surgery without age influence. The impact factor of far foveolar stereo- scopic vision formation is eye position regression. The far stereoscopic vision before surgery is bene- ficial for foveolar stereoscopic vision formation after surgery. So the best opportunity for the surgery is before the loss of far stereoscopic vision. Key words: Intermittent exotropia; Children; Stereoscopic vision; Surgery