PurposeTo compare the outcomes of standard combined Phaco-Kahook Dual Blade (KDB) surgery (GI) with those of the extended technique (GII).MethodsThis retrospective, comparative, multicenter, case-control study enrolled patients with one-year follow-up. GI removed 90° of the trabecular meshwork (TM) extension during KDB, whereas GII removed 150°. The successful criteria were based on a modification of the AAO PPP recommendations - Reporting Clinical Endpoints in Studies of Minimally Invasive Glaucoma Surgery. Qualified success was achieved with or without medication, while absolute success was achieved without the use of any ocular hypotensive medication.ResultsA total of 72 eyes (36 in both groups) were included. The IOP was similar between groups preoperatively (GI: 17.0 ± 2.7 mmHg vs. GII: 17.5 ± 4.2 mmHg, p = 0.5), and at 12 months postoperatively (GI: 13.5 ± 2.8 mmHg vs. GII: 12.3 ± 2.7 mmHg, p = 0.06). The number of glaucoma medications was reduced from 1.7 ± 0.9 to 0.4 ± 0.8 in GI (p < 0.001) and from 2.1 ± 0.8 to 0.4 ± 0.7 in GII (p < 0.001). At 12 months, both groups reduced comparable glaucoma medications (p = 0.9). Qualified success was achieved in 77.1% of the eyes with GI and 94.4% with GII (p = 0.03), whereas complete success was achieved in 68.6% of the eyes with GI and 69.4% with GII (p = 0.7). No serious complications were observed in any of the groups.ConclusionExtended combined Phaco-KDB surgery showed greater relative success than the Standard Phaco-KDB technique. Both techniques achieved similar IOP reduction at 12 months postoperatively.