One-Year Results On Safety Profile And Efficacy Of Trabecular Micro-Bypass System, Istent™ In Various Types Of Glaucoma At A Single Centre.

To evaluate the safety profile and efficacy of Trabecular Micro-bypass system, iStent™ over a period of one year.

A retrospective analysis of electronic patient records following Trabecular micro-bypass sytem in one of the largest tertiary eye units along the south coast in the United Kingdom.

Retrospective, single-centre, analysis of 107 patients who underwent iStent™ procedure with or without phacoemulsification, between July 2016 and November 2020. The primary outcome was to evaluate the intraocular pressure (IOP) recorded at preoperative baseline, first post-operative follow-up, and at one-year.  Complications and success of implantation were also evaluated as secondary outcomes.

128 eyes of 107 patients underwent iStent™ procedure during the 53-month period. The procedure was standalone in 20 eyes while 108 eyes eyes had iStent with phacoemulsification.Primary open angle glaucoma was the common diagnosis at 60.94%.Mean IOP improved by 15.28%, from a mean baseline of 18.20 ± 5.28 mmHg to 15.42 ± 3.95 mmHg at one year postoperatively. Paired t-test showed the IOP reduction was statistically significant (p <0.001). Intraoperative bleeding was seen in 11.27% but hyphema was observed in only one eye, postoperatively. Cystoid macula oedema and postoperative IOP spike (defined as IOP above 21 mmHg) were the common complications, observed in only two cases (1.5%) each.

This real-world study of using iStent corroborates the efficacy and reaffirms the good safety profile of iStent™. The effective reduction of IOP is in all likelihood, independent of initial gain from phacoemulsification that remains sustained over the year.