Clinical Outcomes of Excisional Goniotomy with the Kahook Dual Blade: 6-Year Results

INTRODUCTION: This study aims to evaluate the long-term clinical outcomes of excisional goniotomy with the Kahook Dual Blade (KDB) in the management of various types of glaucoma. METHODS: This was a retrospective, noncomparative chart review of 90 eyes of 53 patients with glaucoma that underwent standalone KDB goniotomy (KDB-alone group) or KDB goniotomy with concomitant phacoemulsification (KDB-phaco group) between October 2015 and October 2017. Surgical success was defined as an intraocular pressure (IOP) reduction by ≥ 20% at the last follow-up with no surgical reinterventions required and a final IOP ≥ 4 mmHg and ≤ 21 mmHg. We also report on changes from baseline in IOP, number of glaucoma medications, best-corrected visual acuity (BCVA), and visual field parameters, for up to 72 months. RESULTS: At 72 months, mean (standard deviation [SD]) IOP was reduced from 17.5 (5.7) to 13.6 (3.0) mmHg (P < 0.0001) in the KDB-phaco group and from 23.3 (5.9) to 15.1 (6.2) mmHg (P = 0.0593) in the KDB-alone group. The mean (SD) number of glaucoma medications was reduced from 1.3 (1.0) to 0.8 (0.9) (P < 0.0001) in the KDB-phaco group and from 1.2 (1.0) to 0.7 (0.8) (P = 0.3409) in the KDB-alone group. During the 72-month follow-up, surgical success was achieved in 24 of the 52 available eyes (46.2%). Four eyes underwent a glaucoma surgical reintervention by 72 months. CONCLUSIONS: Excisional goniotomy with the KDB effectively lowered the IOP (by an average of 28.0% from baseline) and maintained or further reduced glaucoma medication burdens (by an average of 30.8% from baseline) under an excellent safety profile, independent of phacoemulsification status. The procedure exhibited favorable success for up to 6 years, providing valuable insights into its long-term efficacy as a glaucoma treatment.