EFFICACY AND SAFETY OF KAHOOK DUAL BLADE GONIOTOMY AND TRABECULAR MICRO-BYPASS STENT COMBINED WITH CATARACT EXTRACTION: A RETROSPECTIVE STUDY

This study aims to bridge existing research limitations, which have either focused solely on first-generation iStent or limited their scope to mild-to-moderate primary open-angle glaucoma patients, with small samples and outside North America.

Controversy exists regarding the efficacy and safety of Kahook Blade Dual (KDB) goniotomy to that of a second-generation trabecular micro-bypass stent (iStent inject) in combination with cataract extraction.

We performed a retrospective, single-center, observational, longitudinal case series to compare the efficacy and safety of these two types of microinvasive glaucoma surgery (MIGS). The intervention was combined with elective cataract extraction. Data collection included IOP, IOP-lowering medications and best-correct visual acuity (BCVA) preoperatively and at 1 day, 2 weeks, 1 month, 6 months and 12 months 18 months and 24 months postoperatively. In addition, intraoperative and postoperative adverse events were also be examined. The primary efficacy outcome was the proportion of patients in each group attaining 20% reduction of IOP. Subgroup analysis were conducted for different types of glaucoma.

This study included 110 patients (176 eyes), with 88 patients (142 eyes) in the iStent inject group and 22 patients (34 eyes) in the Kahook Dual Blade (KDB) group. A 20% reduction in intraocular pressure (IOP) was achieved by 67% of iStent inject patients and 50% of KDB patients, a difference that was not statistically significant. The iStent inject group showed a higher proportion of patients reaching an IOP of less than 19 mmHg at the final follow-up (81% vs. 71% for the KDB group). Adverse events were more common in the KDB group (47.1% vs. 15.5% for iStent inject), with hyphema and ocular hypertension being the most frequent complications. The KDB group also had a significantly higher failure rate (29.4% vs. 4.2%, p < 0.0001).

Both iStent inject and KDB, in combination with cataract extraction, effectively reduce IOP. However, the KDB procedure is associated with a higher complication and failure rate. Therefore, procedure choice should consider individual patient characteristics, glaucoma severity, and surgeon expertise. Further research is needed to refine patient selection and optimize outcomes.