Surgical Realignment Reverses Contrast Sensitivity Deficits in Children With Intermittent Exotropia: One-Year Results
Yan Yang1, Jiangtao Lou1, Siyu Tan1
1State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, People's Republic of China.
Insights
Children with intermittent exotropia (IXT) have impaired contrast sensitivity function (CSF). Surgical realignment partially improves CSF, suggesting its value in managing pediatric IXT.
Area of Science:
- Ophthalmology
- Pediatric Vision Science
- Neuroscience
Background:
- Intermittent exotropia (IXT) is a common childhood strabismus.
- Visual development, including contrast sensitivity function (CSF), may be affected in children with IXT.
- Understanding CSF development in IXT is crucial for effective management.
Purpose of the Study:
- To investigate the longitudinal development of contrast sensitivity function (CSF) in children with intermittent exotropia (IXT) over one year.
- To evaluate the impact of surgical realignment on CSF in pediatric patients with IXT.
- To compare CSF changes between IXT patients undergoing surgery, those under observation, and healthy controls.
Main Methods:
- Prospective study of 45 children with IXT (7-13 years) and 30 healthy controls.
- IXT patients divided into surgery (n=25) and observation (n=20) groups.
- Binocular and monocular CSF, stereoacuity, and sensory fusion assessed at baseline and 1-year follow-up using CSV-1000E.
Main Results:
- Baseline CSF was significantly worse in the IXT surgery group compared to controls.
- After one year, controls and the IXT surgery group showed significant improvements in binocular CSF.
- The IXT observation group showed no significant CSF changes, while controls had the greatest improvement.
Conclusions:
- Contrast sensitivity function (CSF) is significantly impaired in children with intermittent exotropia (IXT).
- Surgical realignment can partially restore CSF in children with IXT, indicating a potential disruption in visual development.
- CSF assessment offers valuable supplementary data for managing pediatric IXT.
Purpose:
The purpose of this study was to investigate the development of contrast sensitivity function (CSF) in children with intermittent exotropia (IXT) over 1 year and to explore the impact of surgical realignment on CSF.
Methods:
A prospective study of 45 patients with IXT (aged 7-13 years) were matched with 30 healthy controls. Patients with IXT were categorized into the surgery group (n = 25) and the observation group (n = 20). Comprehensive ophthalmic examinations, including binocular and monocular CSF (measured by CSV-1000E), stereoacuity, and sensory fusion, were performed at baseline and the 1-year follow-up.
Results:
At baseline, the IXT surgery group exhibited significantly worse area under the log contrast sensitivity function (AULCSF) and contrast sensitivity (CS) at several spatial frequencies (SFs) compared with the controls (P < 0.05). After 1 year, the control group demonstrated significant improvement in binocular AULCSF and CS at 3, 12, and 18 cycles per degree (cpd; P < 0.05). The surgery group showed significant gains in binocular AULCSF, CS at 3 cpd, and 18 cpd (P < 0.05), whereas the observation group exhibited no significant changes in any metric (P > 0.05). Three-way analysis of covariance (ANCOVA), adjusting for baseline CS, revealed significant main effects of the group, SF, and eye condition on CS change (all P < 0.001), with no significant interactions. Post hoc comparisons showed that the control group had the greatest improvement, followed by the surgery group; whereas the observation group remained lowest across most metrics.
Conclusions:
CSF is significantly impaired in children with IXT. The IXT may disrupt the normal development of contrast processing in children, whereas surgical realignment can partially reverse these effects. CSF assessment may provide valuable adjunctive information for the clinical management of pediatric IXT.
