Posters

Outcomes of iStent alone vs iStent plus ab interno canaloplasty performed during cataract surgery

Poster Details

First Author: M.Abendroth USA

Co Author(s):    M. Pyfer   Q. Zhang                 

Abstract Details

Purpose:

The iStent® (Glaukos, CA, USA) trabecular micro-bypass shunt has become the de facto gold standard Minimally Invasive Glaucoma Surgery procedure due to its excellent safety profile and consistent results. However, a single iStent® reduces intraocular pressure (IOP) only 4 mmHg on average. This study investigates whether combining iStent® with ab-interno viscocanaloplasty using the OMNI™ Surgical System (Sight Sciences, CA, USA) performed with cataract surgery can achieve superior IOP control while maintaining a similar safety profile. The OMNI™ became available in the USA for this study in September 2018.

Setting:

Single surgeon in a private group practice affiliated with Wills Eye Hospital in Philadelphia, PA, USA.

Methods:

Retrospective, consecutive case series of patients with mild to moderate primary open angle glaucoma requiring at least one medication, that underwent cataract surgery with either the iStent® alone or the iStent® plus ab-interno canaloplasty with the OMNI™ between June 2018 and February 2019. Primary outcomes were IOP and number of glaucoma medications. Secondary outcomes were post-operative complications and need for repeat glaucoma procedures. Outcomes were compared using the two-sample t-test, Wilcoxon rank sum test, or chi-square test, as appropriate, with adjustment for two eyes from the same patient.

Results:

The iStent® group had 33 eyes, the combined procedure group 27 eyes. Pre-operatively, mean medicated IOP was 15.7 mmHg and 15.0 mmHg (p=0.45) in the iStent® and combined procedure groups, respectively, and mean number of glaucoma medications was 1.2 and 0.6 (p=0.12). At post-operative month two (n=33 and 7, respectively), mean IOP was 13.1 mmHg and 13.7 mmHg (p=0.30), and mean number of glaucoma medications was 1.0 and 0.0 (p=0.01). The iStent® group had no complications. The combined procedure group had one brief IOP spike and one transient hyphema. No patient experienced corneal edema or intraocular inflammation beyond month one.

Conclusions:

Early results show that combining ab-interno canaloplasty with the iStent® during cataract surgery yields similar IOP reduction to the iStent® alone while requiring significantly fewer glaucoma medications. Complications were uncommon and resolved with medical treatment. No additional glaucoma procedures were required during the study period. This suggests that the combined procedure maintains the excellent safety profile of the iStent® alone. Long-term follow-up and data collection are ongoing.

Financial Disclosure:

None