Evaluation Of The Efficacy And Safety Of A Combined Ab Interno Goniotomy Procedure Using The Kahook Dual Blade Performed Concurrently With Cataract Surgery By Phacoemulsification In The Treatment Of Glaucoma

The aim of this study was to evaluate the safety and efficacy of ab interno goniotomy using the Kahook Dual Blade performed concomitantly with phacoemulsification cataract surgery in lowering intraocular pressure and reducing the number of antiglaucoma medications. The study assessed intraocular pressure (IOP), number of antiglaucoma medications, visual field parameters (Mean Deviation), optic nerve head parameters on OCT (average retinal nerve fiber layer thickness, neuroretinal rim area, and vertical cup-to-disc ratio), best-corrected visual acuity (BCVA), corneal endothelial cell density, and intraoperative and postoperative complications.

This was a single-center retrospective study conducted at the Okulus Plus Ophthalmology Clinic in Poland. Procedures were performed between March 2021 and July 2022. All eyes had a 12-month postoperative follow-up. All surgeries were performed by a single surgeon.

The study included 44 eyes with primary open-angle glaucoma and secondary open-angle glaucoma with coexisting cataract. Indications for surgical treatment included failure to achieve target IOP with topical pharmacological therapy, intolerance or  contraindications to topical antiglaucoma medications, difficulties with eye drop instillation, and/or progression of visual field defects, as well as deterioration of BCVA due to lens opacification meeting the criteria for cataract surgery.

A mean IOP reduction of 18.77% was observed at 6 months and 13.54% at 12 months postoperatively. The mean number of antiglaucoma medications decreased by 22.54% at 6 months and by 26.33% at 12 months postoperatively.

No statistically significant progression was observed on OCT of the optic nerve head (aRNFL thickness, neuroretinal rim area, vertical C/D ratio). Mean deviation (MD) improved significantly on visual field testing (p < 0.025), and BCVA improved significantly postoperatively from 0.46 to 0.78 at 6 months and 0.71 at 12 months of follow-up. A slight decrease in corneal endothelial cell density was noted from 2357,91  to 2113,17 cells/mm². The most frequent complications were transient IOP elevation and transient hyphema.

The results of this study suggest that ab interno goniotomy using the Kahook Dual Blade performed in combination with cataract phacoemulsification is a safe procedure that provides stabilization of visual field parameters (MD), optic nerve head optical coherence tomography parameters (aRNFL thickness, neuroretinal rim area, vertical C/D ratio), improvement in BCVA, and a simultaneous significant reduction in intraocular pressure and the number of antiglaucoma medications.