Changes in Palpebral Fissure Height after Lateral Rectus Muscle Recession with and without Intermascular Septum Dissection: A Prospective Interventional Cohort Study

Propose: To evaluate the effect of lateral rectus muscle recession with and without intermascular septum dissection on palpebral fissure height.
Twenty-five eyes of 15 patients (10 patients with bilateral and 5 patients with unilateral procedure) and 26 eyes of 19 patients (7 patients with bilateral and 12 patients with unilateral procedure) were assigned to lateral rectus muscle recession 'with' or 'without' intermuscular septum dissection, respectively. The palpebral fissure height was measured preoperatively and three months postoperatively and compared between the study groups.
Compared to preoperative values, a significant increase in palpebral fissure height was observed in both groups 3 months postoperatively (Paired T-test; p Intermuscular septum dissection is recommended during lateral rectus muscle recession to decrease undesirable widening of palpebral fissure width.