A Quantitative Approach To Shortening The Levator Palpebrae Superioris To Correct Congenital Ptosis Under General Anesthesia

Objective:Shortening the levator palpebrae superioris(LPS)is difficult in children because they are unable to open their eyes while under general anesthesia,nor are they able to fully cooperate during preoperative examination.This study aimed to develop a feasible method to mitigate these problems.Method:Sixty-four patients(102 eyelids)were divided into three groups based on the degree of ptosis: mild,moderate,and severe.All patients underwent the same levator resection surgery in which the suspensory system of the LPS is retained.After capturing a standard photograph of primary position,the height of the superior palpebral margin was measured preoperatively using imaging software to calculate its ideal height required during surgery.Postoperative outcome measures included upper eyelid margin height,degree of scleral exposure,and exposure keratitis.The patients were followed-up at 1 week,and 1 and 6 months postoperatively.Result:In the early postoperative period,except two cases with overcorrection,the positions of the eyelid upper margins were normal in all cases in the mild and moderate groups.One month after surgery,one overcorrected eyelid in the mild group was still in its original state,the overcorrected eyelid in the moderate group improved to a normal degree.However,in the severe group,there was a recurrent tendency in seven eyelids.The height was 7 mm and 8 mm,between the upper margin and inferior limbus,respectively;others were maintained within the normal range.In mild cases,the eyelids could be completely closed,and the scleral exposure improved in all patients.Six months postoperatively,the eye with overcorrection in the moderate group showed improvement,while the eye in the mild group did not.Seven eyes in the severe group exhibited residual ptosis to varying degrees.The eyelids exhibited appropriate closing functionality;exposure keratitis was absent.Conclusion:Using this preoperative quantification technique to guide surgery not only provided a gauge for LPS shortening under general anesthesia,but also increased the success rate of surgery.