Twelve-month results of ab interno trabeculectomy with Kahook Dual Blade: an interventional, randomized, controlled clinical study

Purpose: To evaluate the efficacy and safety profile of Kahook Dual Blade ab interno trabeculectomy combined with phacoemulsification compared to stand-alone conventional cataract surgery.

Methods: A single-center longitudinal, randomized controlled trial was conducted. Patients older than 18 years with coexisting cataract and open-angle glaucoma or ocular hypertension were invited to participate. Preoperative and postoperative clinical data were collected and analyzed preoperatively and at months 1, 3, 6, and 12 after the procedure. Main outcome measures included best corrected visual acuity, intraocular pressure, number of glaucoma medications, endothelial cell count, and standard automated perimetry.

Results: Forty-two eyes from 33 patients were randomly allocated to the combined cataract and KDB (treatment, n = 21) or cataract alone (control, n = 21) groups. Intraocular pressure decreased from 17.9 ± 3.5 to 16.0 ± 2.2 mmHg and from 17.3 ± 2.5 to 15 ± 3.2 mmHg at the last visit in the treatment and control groups (p = 0.47). The use of glaucoma medications was reduced from a median (IQR) 1 (1-2) to 0 (0-0) in the treatment group and from 1 (1-2) to 0 (0-1) in the control group, with no significant differences between groups at the 12-month visit (p = 0.47). Best corrected visual acuity, endothelial cell count, and standard automated perimetry remained similar during follow-up in both groups.

Conclusions: In patients with well-controlled, mild-to-moderate glaucoma, adding ab interno trabeculectomy with KDB to phacoemulsification might not be more effective than phacoemulsification alone to reach mid-teens IOP values. Both procedures showed similar safety profiles.

Trial registration: ClinicalTrials.gov Identifier: NCT04202562, December 17, 2019 retrospectively registered.