Slow-releasing tranilast in polytetrafluoroethylene/polylactide-co-glycolide laminate delays adjustment after strabismus surgery in rabbit model

Abstract

PURPOSE: To determine the usefulness of slow-releasing tranilast in polytetrafluoroethylene/polylactide-co-glycolide (PTFE/PLGA) laminate for delayed adjustable strabismus surgery. METHODS: A prospective, masked-observer, controlled study was performed in 25 rabbits. Fifty rabbit eyes were divided randomly into three groups. After a recession of the superior rectus muscle (SRM), a PTFE/PLGA laminate containing tranilast, PTFE alone, or balanced salt solution was applied beneath and over the SRM in the PTFE/PLGA-tranilast group (group P-T), the PTFE group (group P), and the control group, respectively. Delayed adjustment was performed by a masked observer once on each SRM 3 or 5 weeks after surgery. Adjustability, adjustment lengths, forces required, and adhesion degrees were evaluated. RESULTS: In the control group, adjustment was impossible in any eye 3 or 5 weeks after surgery. In group P, adjustment was possible in 5 of 8 eyes 3 weeks after surgery and in 5 of 10 eyes 5 weeks after surgery. In group P-T, adjustment was possible in 8 of 10 eyes 3 and 5 weeks after surgery. On comparing adjustability, a significant difference was observed between group P-T and the control group 3 and 5 weeks after surgery (P = 0.006, P = 0.006, respectively). A significant difference was observed between group P-T and the control group (P = 0.016) in terms of adhesion between SRMs and conjunctivae 5 weeks after surgery. CONCLUSIONS: Slow-releasing tranilast in PTFE/PLGA was found to reduce adhesion and allowed delayed adjustment in most eyes for up to 5 weeks after surgery.