Augmented Recession by Intraoperative Botulinum Toxin-A Injection in Large Angle Horizontal Deviation

Purpose : The aim of this study is to evaluate the effectiveness of intraoperative botulinum toxin-A (BTA) injection as an adjunct to the surgical treatment of large-angle esotropia or exotropia.Methods : Thirteen patients were included in this interventional case series study. Mean age of the patients was 23.31±13.29 years (range: 5-43 years). Of these 13 patients, 6 were exotropic and 7 were esotropic. The average preoperative esodeviation was 79.29±16.44 prism diopters (PD) (range: 60-100 PD) and exodeviation was 75.83±11.14 PD (range: 65-90 PD). Depending on the degree of deviation ten or twenty units of Dysport were injected intraoperatively into the recessed horizontal rectus muscles in all of the patients.Results : The average follow-up was 7±1 months (range: 6-8 months). The average final deviation in the esotropia group was 8.57±10.69 PD of esotropia. The average final deviation in the exotropia group was 14.17±12.00 PD of exotropia. The final deviation of the 69% patients was within 15 PD of esotropia or exotropia.Conclusion : This study shows that the combination of BTA injection with recession may be a useful treatment option in cases of large angle horizontal deviation