Goniotomy Using the Kahook Dual Blade in Severe and Refractory Glaucoma: 6-Month Outcomes

Purpose: The purpose of the study is to describe short-term efficacy and safety of goniotomy with trabecular meshwork excision using the Kahook Dual Blade (KDB, New World Medical Inc., Rancho Cucamonga, CA) in patients with severe or refractory glaucoma. Method: Retrospective multicentric case series of 53 eyes with severe or refractory glaucoma as defined by ICD-10 conducted in the United States, Mexico, and Switzerland. Primary efficacy outcome was a >= 20% decrease in intraocular pressure (IOP) from baseline at 6 months. Secondary efficacy outcome measures were probability of achieving an IOP <= 14 or 18 mm Hg at 6 months and the mean IOP change from baseline at 6 months. Medication use required to obtain target IOP at last follow up and adverse effects were analyzed. Results: The proportion of eyes achieving an IOP reduction of >20% from preoperative baseline at 6 months was 57.7% (n=30). The mean IOP decreased from 18.4 +/- 6.1 mm Hg at baseline to 13.9 +/- 3.5 mm Hg at month 6 (23.9% reduction; P<0.001). At 6 months, 63.5% and 92.3% achieved an IOP <= 14 and <= 18 mm Hg, respectively, and the mean number of glaucoma medications was reduced by 1.2 +/- 1.3 (36.6%) compared with baseline (P<0.001). The most common adverse event was hyphema (n=29, 34.9%) with spontaneous resolution in all cases. No severe complications were reported. One case presented with uncontrolled IOP and required glaucoma drainage device surgery at 1 month. Conclusions: Goniotomy with trabecular meshwork excision using the KDB could be an alternative surgery for severe or refractory glaucoma, significantly reducing IOP and medication use at 6 months, with a low rate of complications.