A Study On The Quantitative-effective Relationship Of Retroflexion Of The External Rectus Muscle In Children With Intermittent External Strabismus Surgery

ObjectiveThe high prevalence and unknown pathogenesis of intermittent exotropia have led to different views on the type of surgery to be used,and the uncertainty of surgical efficacy is due to the varying quantitative-effective relationships of various surgical designs.The variability of strabismus in intermittent exotropia and the problem of postoperative recurrence(especially distant undercorrection)have always troubled ophthalmologists.In this study,we established a quantitative relationship between the amount of external rectus regression and several influencing factors in a group of children with intermittent exotropia who maintained normal eye position for more than six months after surgery,and then verified the quantitative relationship with a group of children with intermittent exotropia who had undergone external rectus regression and were not included in the modeling,in order to expect a more accurate quantitative surgical protocol for future patients with intermittent exotropia who underwent external rectus regression,and thus improve The results of the surgical treatment of intermittent exotropia will be improved.MethodsData from a group of 93 children who were diagnosed with intermittent external strabismus from October 2019 to September 2022 at Guangzhou Women’s and Children’s Medical Center and who underwent external rectus regression and were followed up for six months(or more)postoperatively with an orthotropic eye position were reviewed,data characteristics of this sample set were summarized and analyzed,and the amount of external rectus regression was modeled and initially validated using the Lasso regression method.Results1.There was a statistically significant difference between the two groups of preoperative and postoperative Worth four-point light examination results in children with intermittent external strabismus.2.Analysis of the data from the two groups of children with intermittent external strabismus showed no significant differences in age of onset,gender,and weight,while there were significant differences in age at surgery,amblyopia,refractive error,strabismus degree,strabismus type,and amount of external rectus recession.3.The mathematical models constructed using the Lasso regression model for the data of different strabismus degree groups were,in descending order of goodness of fit,the strabismus degree group for surgical volume design,the strabismus degree group measured by the trigeminal lens with mask,the strabismus degree group measured by the computer-assisted objective quantitative diagnosis technique of childhood strabismus,and the strabismus degree group obtained by the corneal reflectance method.In addition,there was no significant difference in the number of children with intermittent exotropia who referred to the trigeminal plus masking method for the design of surgery in each age group;there was a significant difference in the number of children with intermittent exotropia who referred to the computer-assisted child strabismus objective quantitative diagnosis technique in each age group.4.Lasso regression is a model that can be constructed for the amount of external rectus regression in children with intermittent exotropia,which incorporates variables such as age at surgery,age at onset,and the magnitude of strabismus,with the following model: amount of external rectus regression(mm)= 0.0125 × age at surgery(months)-0.0026 × age at onset(months)+ 0.526 × magnitude of strabismus(°)-1.078;using data from children with intermittent exotropia who had not Data from children with intermittent external strabismus who had undergone external rectus regression included in this study were compared to the predicted and actual values of external rectus regression by the model of Lasso regression,and the results showed no significant difference.Conclusions1.This study used Lasso regression to establish the quantitative relationship between the amount of external rectus muscle regression and the degree of strabismus,age at surgery and age of onset in children operated for intermittent external strabismus.2.The established quantitative-effective relationships were verified to be feasible by external data.3.Assists in providing a tool for more precise quantitative surgical design and improved surgical outcomes in children with intermittent exotropia.