Combined Phacoemulsification and Hydrus Microstent Implantation in Asian Eyes with Moderate-to-Severe Normal Tension Glaucoma - 12-Month Outcomes.

Abstract

This study reports 12-month outcomes of combined phacoemulsification and Hydrus Microstent implantation in Asian eyes with moderate-to-severe normal tension glaucoma, demonstrating a significant reduction in glaucoma medications with an excellent intra- and post-operative safety profile. To evaluate the 12-month safety and efficacy outcomes of combined phacoemulsification and Hydrus Microstent (Ivantis Inc., Irvine, CA) implantation in Asian eyes with moderate to severe normal tension glaucoma (NTG). Retrospective study of consecutive surgeries performed from August 2019 to August 2021 in a single tertiary eye centre in Singapore. Outcome measures included reduction in intraocular pressure (IOP), number of glaucoma medications, and intra- and post-operative complications. Data from 21 eyes of 21 subjects was analysed. All subjects were ethnic Chinese and majority were male (14, 66.7%). At baseline, mean IOP was 13.3 (2.3) mmHg, all eyes had a Humphrey Visual Field (HVF) mean deviation (MD) of ≥-6dB [mean -13.9 (4.3) dB] and all eyes were on at least one glaucoma medication. There was no statistically significant reduction in IOP at all timepoints compared to baseline (all P>0.05). However, median number of medications was reduced from 2 to 0 at all timepoints, up to POM12 (all P<0.001). There were no intraoperative complications. No eyes underwent secondary glaucoma procedures nor lost any Snellen's line of visual acuity by POM12. One (4.8%) eye experienced numerical hypotony at POD1, which resolved conservatively. Two (9.5%) eyes underwent laser iridoplasty for stent occlusion by iris. There was no deterioration in HVF MD at POM12 compared to baseline (n=20, P>0.05). Combined phacoemulsification and Hydrus Microstent implantation was effective in reducing medication burden in Asian eyes with moderate to severe NTG, up to 12 months post-operatively.