Surgical Outcomes of Ab Interno Trabeculotomy Without Phacoemulsification.

Purpose: The aim of this study was to evaluate ab interno trabeculotomy outcomes without phacoemulsification.

Methods: This retrospective study evaluated 118 eyes of patients aged 18 and above who underwent ab interno trabeculotomy between December 2017 and August 2022. When surgeries were performed in both eyes, only the eye undergoing the initial surgery was evaluated. Prior to and after surgery, the intraocular pressure (IOP) and mean number of IOP-lowering medications were compared. An IOP of ≤21 mmHg (A) and ≤18 mmHg (B) along with a ≥20% reduction in the preoperative IOP was defined as survival. Cases that required reoperation for glaucoma were defined as surgical failure. The Kaplan-Meier method was used to evaluate the survival rates. A Cox proportional hazards model was used to analyze the preoperative factors that influenced survival rates.

Results: At 36 months postoperatively, the 13.4 ± 2.8 mmHg average IOP was significantly decreased from the preoperative 23.5 ± 9.8 mmHg value ( < 0.0001). Moreover, a significant decrease in the mean number of the IOP-lowering medications to 2.3 ± 1.4 at 36 months was found versus the initial 3.9 ± 1.1 preoperative value ( < 0.0001). The survival rates for criteria A and B at 36 months postoperatively were 28% and 25%, respectively. Only the preoperative IOP was identified by multivariate analysis as a factor influencing survival rates ( < 0.0001). Hyphema in 36 eyes (30.5%) and an IOP spike in 20 eyes (16.9%) were the only observed complications. Additional glaucoma surgery was required in 27 eyes (22.9%) during the follow-up period.

Conclusion: Utilization of ab interno trabeculotomy effectively lowered the IOP and reduced the number of IOP-lowering medications. Patients with higher preoperative IOP exhibited better postoperative outcomes.