Outcomes of standalone ab interno trabeculotomy in the treatment of open-angle glaucoma in eyes with high myopia

Abstract Background We retrospectively evaluate the long-term efficacy and safety of trabeculotomy glaucoma surgery in treating open-angle glaucoma (OAG) in eyes with high myopia (HM). Methods This study included 20 eyes with HM (axial length ≥ 26.5 mm) and OAG; age, preoperative IOP (intraocular pressure), and sex-matched 20 non-HM eyes (axial length < 26.5 mm) served as controls. Each eye underwent standalone ab interno trabeculotomy using a Kahook dual blade. A follow-up examination was performed 36 months after surgery. The main outcome measure was the operative success rate (i.e., a ≥ 20% pre- to post-operative reduction in IOP with or without IOP-lowering medication). Kaplan–Meier analysis was employed as a measure of surgical success. The secondary outcome measures were postoperative IOP, the number of glaucoma medications, and postoperative complications. Results IOP and the number of glaucoma medications were statistically significantly reduced at all postoperative follow-up examinations. The Kaplan–Meier analysis demonstrated that the probability of postoperative success at 36 months was 45% and 65% for HM and non-HM eyes, respectively. In the HM group, the presence of pathological myopia was statistically significant risk factor for surgical failure. No critical postoperative complications were detected. Conclusions In our study, the long-term efficacy of ab interno trabeculotomy in HM eyes with OAG was inferior to that in non-HM eyes with OAG. Our findings suggest that surgical indications for trabeculotomy in HM should be determined based on the presence of pathological myopia.