Factors Influencing the Lagophthalmos and Lid Lag After Simple Congenital Blepharoptosis Correction

Background:Lagophthalmos and lid lag is the most common complication after ptosis correction. Great efforts had been made to control it, but little was known about the factors influencing it. So we ran this research to explore the possible mechanisms underlying it. This would be beneficial to solving this problem. Materials and Methods:In this cohort study, patients treated with the forked frontalis muscle aponeurosis suspension and levator aponeurosis-Muller's muscle complex resection were identified. Lagophthalmos height and lid lag was measured at the postoperative week 1 visits. The Spearman correlation test was run to test whether lagophthalmos was related to patients' age, levator function, and severity of ptosis. Then we measured the contents of collagen and elastin fibers of frontalis muscle fascia and levator aponeurosis from the patients and levator aponeurosis from cadaver heads histologically and compared the contents in these 3 groups. Results:No correlation was found between patients' age, levator function, the severity of ptosis, and with lagophthalmos height. However, the contents of collagen and elastic fibers were both higher in the frontalis fascia than in the normal aponeurosis tissues. The difference in collagen fibers content between frontalis muscle fascia and patients' aponeurosis was statistically insignificant. Conclusions:The severe lagophthalmos and lid lag may be caused by the poor mechanical features of the frontalis muscle. A better source of motive force to elevate the eyelids and a novel sling material with proper elasticity and stiffness would be the solution to improve the lagophthalmos and lid lag after ptosis correction.