Change in Contrast Sensitivity after Surgery for Consecutive Esotropia

Abstract

This study compared the contrast sensitivity before and after surgery for intermittent exotropia and consecutive esotropia and examined the correlation between contrast sensitivity and other visual function factors. Methods: The medical records of patients who underwent surgery for consecutive esotropia after surgery for intermittent exotropia were analyzed retrospectively. To analyze changes after each surgery, contrast sensitivity was tested before surgery for exotropia, before surgery for consecutive esotropia, and 3 months after surgery for consecutive esotropia. The changes in contrast sensitivity were analyzed, and correlation analyses between contrast sensitivity and the Titmus test and Worth 4 Dot (W4D) test were performed. Results: The study included 14 patients. In consecutive esotropia, the contrast sensitivity was significantly improved at 7.1 and 10.2 cycles per degree (cpd) under mesopic conditions in the presence of glare and at 10.2 cpd under photopic conditions with and without glare after esotropia surgery (p < 0.05). There was a significant negative correlation between contrast sensitivity and stereopsis at 1.1 cpd under photopic conditions without glare before esotropia surgery (p = 0.011). Comparing the contrast sensitivity according to the W4D results, the fusion group had significantly better contrast sensitivity than the non-fusion group at 10.2 cpd under photopic conditions without glare and 2.9, 4.5, and 7.1 cpd with glare before exotropia surgery (p < 0.05). Conclusions:The contrast sensitivity at high spatial frequencies improved after surgery for consecutive esotropia and there was a significant negative correlation between the contrast sensitivity and stereopsis in consecutive esotropia. This means that in patients with esotropia, the contrast sensitivity test is an indirect indicator of visual function.