Foreign body extrusion associated with N-butyl-2-cyanoacrylate glue used with rectus muscle hang-back recession

Standard rectus muscle recessions require suturing muscle to sclera posterior to the insertion, which is dangerous as the sclera is thin. Extraocular muscle hang-back recession can avoid the posterior scleral needle pass but has been reported to be unstable. The purpose of this study is to assess the use of N-butyl-2-cyanoacrylate to aid reattachment of rectus muscle to sclera during hang-back recession.2 Phase Study: Phase 1 was a wet lab animal study; Phase 2 was a small case series.Phase 1, 14 frozen bank rabbit heads; Phase 2, 4 human adult patients with myopia and large exotropia.Phase 1: Frozen bank rabbit heads were used to simulate human hang-back rectus muscle recession. Fourteen rectus muscles were recessed by hang-back and glued to sclera with either cyanoacrylate glue alone (group 1) or glue over prolene mesh for greater stability (group 2). Primary outcome was muscle detachment force measured at 20, 30, and 40 seconds. Phase 2: Four patients with myopia and large exotropia who underwent bilateral hang-back lateral rectus recessions with cyanoacrylate glue were retrospectively studied.Phase 1: Group 1 mean detachment force measured at 30 seconds was 172.07 g versus 376.5 g in group 2 (p0.01). Phase 2: All patients had excellent postoperative alignment within 5 PD of orthophoria and no overcorrections. Two patients had unilateral glue extrusion at 1 month requiring in-office removal under topical anaesthesia.Cyanoacrylate glue with or without mesh resulted in adequate muscle-to-sclera adhesion with a detachment force at least 2 times the force of a normal rectus muscle contraction. Patients undergoing hang-back lateral rectus recession with cyanoacrylate glue had excellent stable postoperative alignment; however, half had the complication of late extrusion of glue foreign body.