Outcomes of iStent Inject Versus Kahook Dual Blade Surgery in Glaucoma Patients Undergoing Cataract Surgery

Abstract

Précis: iStent Inject implantation (iStent) or Kahook Dual Blade goniotomy (KDB) in combination with phacoemulsification have a similar IOP-lowering effect in all stages of glaucoma, and medications are significantly reduced, especially after KDB.Purpose: To compare the 2-year efficacy and safety of iStent or KDB in combination with phacoemulsification in eyes with mild to advanced open angle glaucoma.Methods: A retrospective chart review of 153 patients that received iStent or KDB in combination with phacoemulsification at a single center between March 2019 and August 2020. The main outcome parameters at 2 years were: (1) intraocular pressure (IOP)-reduction ≥ 20%, with a postoperative IOP ≤ 18 mm Hg, and (2) a reduction of ≥ 1 medication. Results were stratified by glaucoma grade.Results: After 2 years, mean IOP was reduced from 20.3 ± 6.1 to 14.2 ± 4.1 mm Hg in the phaco-iStent group (P < 0.001) and from 20.1 ± 6.1 to 14.7 ± 3.6 mm Hg in the phaco-KDB group (P < 0.001). The mean number of medications was reduced from 3.0 ± 0.9 to 2.6 ± 1.1 in the Phaco-iStent group (P = 0.001) and from 2.3 ± 1.0 to 1.5 ± 1.3 in the Phaco-KDB group (P < 0.001). Success regarding IOP-reduction ≥ 20% with a postoperative IOP ≤ 18 mm Hg was met by 46% in the phaco-iStent group and by 51% in the phaco-KDB group. A reduction of ≥ 1 medication was met by 32% in the phaco-iStent group and by 53% in the phaco-KDB group (P = 0.013). Eyes with mild to moderate and advanced glaucoma responded equally well to the success criteria.Conclusions: iStent and KDB, in combination with phacoemulsification, both lowered IOP effectively in all stages of glaucoma. More medications were reduced after KDB, suggesting that it may be a more effective procedure compared with iStent.

Fellow-Eye Comparison between Phaco-Tanito Microhook Trabeculotomy and Phaco-iStent Inject W

“…Previously, in an intraindividual comparative study over a 12-months follow-up in POAG, Trabectome and the iStent inject W were both effective in lowering IOP without a significant difference between the two groups [15]. On the other hand, KDB seemed to offer an advantageous IOP reduction compared to the first-generation iStent [5][6][7][8] and even compared to the iStent inject W [9,16]. From other groups, equivalence in IOP reduction between TMH and KDB were reported [17,18].…”

“…Currently, the iStent is available in two generations: the first-generation iStent and second-generation iStent Inject W. Previously, multiple studies were conducted to compare the effectiveness and safety of MIGS procedures between Kahook Dual Blade (KDB) and the first- [5][6][7][8] or second-generation [9] iStent. In our previous report, fellow-eye comparison showed that the IOP reduction was greater with TMH than with the first-generation iStent when combined with cataract surgery [10].…”

Comparison of Phaco-Tanito Microhook Trabeculotomy between Propensity-Score-Matched 120-Degree and 240-Degree Incision Groups

“…Other studies have reported greater IOP reductions with goniotomy using a Kahook Dual Blade (KDB) at 90 degrees compared to the first-generation iStent trabecular bypass implantation with one 120 µm-lumen stent [22][23][24][25] or the second-generation iStent inject W with two 80 µm-lumen stents [26,27]. In our previous studies, fellow-eye comparisons demonstrated a greater IOP reduction with TMH than with both the first- [28] and second- [29] generation iStent when combined with cataract surgery.…”

Functional assessment of trabecular bypass created by iStent inject using aqueous angiography

“…Previous studies have reported that phacoemulsification combined with iStent inject can decrease IOP by 2.4 mm Hg to 6.1 mm Hg in the postoperative period 2 3. Implantation of iStent inject alone can decrease IOP by approximately 2.3–4.3 mm Hg in the postoperative period 4.…”