A multicenter retrospective comparison of goniotomy versus trabecular bypass device implantation in glaucoma patients undergoing cataract extraction

Abstract

Purpose

The aim of this study was to compare intraocular pressure (IOP) outcomes in eyes with cataract and glaucoma undergoing phacoemulsification (phaco) in combination with goniotomy using the Kahook Dual Blade (KDB) or implantation of a single iStent trabecular bypass device.

Methods

Retrospective analysis of IOP and IOP-lowering medication reduction in eyes undergoing phaco-goniotomy with KDB (n=237) or phaco-iStent (n=198). Preoperative, intraoperative, and postoperative data were collected through 6 months of follow-up. Outcome measures included mean IOP reduction, mean reduction in IOP-lowering medications, and the proportion of eyes achieving ≥20% IOP reduction or ≥1 medication reduction from baseline.

Results

Mean IOP in the phaco-goniotomy with KDB group decreased from 17.9±4.4 mmHg at baseline to 13.6±2.7 mmHg at Month 6 (P<0.001), with mean medication use decreasing from 1.7±0.9 to 0.6±1.0 (P<0.001). In the phaco-iStent group, mean IOP decreased from 16.7±4.4 mmHg to 13.9±2.7 mmHg (P<0.001), with mean IOP-lowering medication use decreasing from 1.9±0.9 to 1.0±1.0 (P<0.001). Mean IOP reduction from baseline was significantly greater in the phaco-goniotomy with KDB group at Month 6 (phaco-goniotomy with KDB −4.2 mmHg [23.7%] vs phaco-iStent −2.7 mmHg [16.4%]; P<0.001). IOP-lowering medication reduction was greater in the phaco-goniotomy with KDB group compared to the phaco-iStent group (1.1 vs 0.9 medications, respectively; P=0.001). The most common adverse event was IOP spikes occurring in 12.6% of phaco-iStent eyes and 6.3% of phaco-goniotomy with KDB eyes (P=0.024).

Conclusion

Goniotomy with the KDB combined with cataract surgery significantly lowers both IOP and the need for IOP-lowering medications compared to cataract extraction with iStent implantation in glaucomatous eyes through 6 months of postoperative follow-up.

Keywords:

• glaucoma
• goniotomy
• intraocular pressure

Acknowledgments

We would like to thank the following for their substantial contribution in this study: Suhail Abdullah, MBSc, for significant contribution to the study design and review of article; Mark C Jasek, PhD, for providing consultations in study design, analysis, and interpretation of data as well as critical review of the article; Khaled Bahjri, MD, MPH, PhD, for assisting in data collection, analysis, and interpretation of findings; and Anthony Realini, MD, for assisting in writing the article. The KDB Goniotomy Study Group members include Syril K Dorairaj, MD; Gabriel S Lazcano-Gomez, MD; Sidney T Chang, MD; Leonard A Rappaport, MD; Mohammed ElMallah, MD; Hylton R Mayer, MD; Blake K Williamson, MD; Leonard K Seibold, MD; Ahad Mahootchi, MD; Mina B Pantcheva, MD; Sanjay N Smith, MD; Shobit Rastogi, MD; Malik Y Kahook, MD; and Inder P Singh, MD.

Disclosure

All authors have received research support from New World Medical in the past. No financial support was received for the work involved in this article. Drs Dorairaj, Kahook, Williamson, Seibold, and Singh are consultants for New World Medical. Dr Kahook receives royalties from licensed patents pertaining to the KDB. Dr ElMallah has no relevant financial disclosures. The authors report no other conflicts of interest in this work.