Surgical Outcomes of Phacoemulsification Followed by iStent Implantation Versus Goniotomy With the Kahook Dual Blade in Patients With Mild Primary Open-angle Glaucoma With a Minimum of 12-Month Follow-up.

Abstract

To study surgical outcomes after combined phacoemulsification with either iStent implantation or goniotomy using the Kahook Dual Blade (KDB) with a minimum of 12 months of follow-up. Patients with mild primary open-angle glaucoma who underwent phacoemulsification in combination with either iStent implantation or goniotomy using the KDB from 2011 to 2017 were included. In total, 48 eyes in the iStent group and 29 eyes in the KDB group were included with at least 12 months of follow-up. There was no difference in patient age, sex, previous surgery, preoperative or postoperative visual acuity or intraocular pressure (IOP) between the 2 groups. Mean preoperative IOP in the iStent group decreased from 17.6±4.8 to 15.9±2.9 mm Hg (P=0.01); mean preoperative IOP in the KDB group decreased from 17.4± 4.3 to 15.0±4.0 mm Hg (P=0.01). The overall percentage of IOP reduction was 14.3% in the iStent group and 12.6% in the KDB group at 12 months of follow-up. Mean topical glaucoma medication use decreased from 2.0±0.9 to 0.7±1.1 in the iStent group and from 2.2±1.0 to 1.6±1.3 in the KDB group. Multivariable linear regression accounting for age, sex, race, baseline IOP, and number of eyes treated as covariates indicated a significant reduction in IOP from baseline with both iStent (Wald χ=3.97, P=0.046) and KDB (Wald χ=4.65, P=0.031). Multivariable logistic regression accounting for age, sex, race, baseline IOP, and number of eyes treated as covariates indicated no significant difference in overall success between iStent and KDB (Z-test=0.92, P=0.359). Phacoemulsification in combination with either iStent implantation or goniotomy using the KDB both achieved statistical significant reduction in IOP and number of glaucoma medications at 12 months of follow-up in patients with mild primary open-angle glaucoma with no complications.