Journal of Current Glaucoma Practice

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VOLUME 16 , ISSUE 1 ( January-April, 2022 ) > List of Articles


Predictive Factors of Outcomes in Kahook Dual Blade Excisional Goniotomy Combined with Phacoemulsification

Eli L Pratte, Junsang Cho, James R Landreneau, Matthew T Hirabayashi, Jella A An

Keywords : Kahook dual blade, Outcomes, Retrospective study, Risk factors

Citation Information : Pratte EL, Cho J, Landreneau JR, Hirabayashi MT, An JA. Predictive Factors of Outcomes in Kahook Dual Blade Excisional Goniotomy Combined with Phacoemulsification. J Curr Glaucoma Pract 2022; 16 (1):47-52.

DOI: 10.5005/jp-journals-10078-1313

License: CC BY-NC 4.0

Published Online: 03-05-2022

Copyright Statement:  Copyright © 2022; The Author(s).


Aim: To identify factors that were significant predictors of Kahook Dual Blade (KDB) excisional goniotomy outcomes. Materials and methods: One hundred and thirty-two eyes from 99 adult glaucoma patients who underwent combined KDB and phacoemulsification (KDB-phaco) with a minimum 6-month follow-up were assessed for baseline patient characteristics to determine correlation to the success of KDB-phaco at 6 and 12 months postoperatively. Success was defined as ≥20% intraocular pressure (IOP) reduction or ≥1 medication reduction as well as IOP ≤18 mm Hg without any additional IOP-lowering procedures after KDB-phaco. Results: 63.6% (84/132) and 46.1% (41/89) of cases were successful at the 6- and 12-month follow-ups, respectively. KDB-phaco reduced patient's preoperative IOP (in mm Hg) from 17.6 ± 4.6 to 14.9 ± 3.2 at 6 months (15.3%, p < 0.001) and 15.4 ± 4.7 at 12 months (12.5%, p = 0.001). KDB-phaco reduced patient's preoperative IOP-lowering medications from 2 ± 1.2 to 1.1 ± 1.2 at 6 months (45%, p < 0.001) and 1.32 ± 1.3 at 12 months (34%, p < 0.001). At 6 months, patients on >1 IOP lowering medication had a greater chance of meeting our success criteria (p = 0.037). Visually significant postoperative hyphema was not associated with the use of anticoagulation (p = 0.943) but was significantly associated with postoperative day 1 IOP ≤ 10 mm Hg (p = 0.011). Conclusion: Patients who underwent KDB-phaco significantly reduced their IOP and medication burden at both 6 and 12 months compared with their baseline preoperative values. KDB-phaco outcome was associated with higher baseline IOP-lowering medications and increased rate of hyphema was associated with lower postoperative day 1 IOP, regardless of anticoagulation status. Age, ethnicity, prior laser trabeculoplasty, type and severity of glaucoma, and baseline preoperative IOP were not associated with surgical success. Clinical significance: Patients with a higher number of baseline medications may experience a greater probability of success following KDB-phaco.

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