Evaluation of Intraoperative Lagophthalmos Formula

This is a prospective non-randomized study to evaluate the recent intraoperative lagophthalmos formula method for levator resection in determining postoperative eyelid height in congenital ptosis on Egyptian children. The study included 20 eyelids of 17 Egyptian children with congenital ptosis with levator function of 4mm or better, they underwent levator muscle resection guided by the recent intraoperative lagophthalmos formula. Preoperative MRD 1 (Margin-to-reflex distance 1) and levator function were measured, then intraoperative palpebral fissure opening was determined from formula: Intraoperative lagophthalmos=9.08 - 0.48×Preoperative MRD1 - 0.26× Levator function. Postoperative MRD 1 was measured after 1 day, 1week,1month, 3 months and 6 months .Success was defined as postoperative MRD 1 ≥ 3 mm and difference between both eyelids height ≤ 1 mm at 6 months.