ABSTRACT.Purpose: To compare 1.8 mm micro-incision and 2.75 mm standard incision in coaxial cataract surgery combined with 23-Gauge (23G) vitrectomy with respect to intraoperative and postoperative complications and outcomes. Methods: In this prospective study 30 eyes of 30 patients planned for combined phacoemulsification and 23G vitrectomy were enrolled, and randomized to undergo either Standard 2.75 mm Incision Cataract Surgery (SICS, 15 eyes) or Coaxial 1.8 mm Micro-Incision Cataract Surgery (C-MICS, 15 eyes) followed by vitrectomy. Inclusion criteria were cataract and macular disorders including macular hole, epiretinal membrane and vitreomacular traction. Data were collected at preoperative evaluation and 1 and 12 months or more after surgery. Results: Incision leakage occurred in two eyes (7%: one per group), retinal break in nine (30%: four in C-MICS, five in SICS). Fibrin in anterior chamber (AC) occurred day 1 in three eyes (10%: two C-and one SICS). Posterior capsule opacification developed in 22 eyes (78%: 13 MICS, nine SICS, p = 0.1). A myopic shift of À0.63 AE 0.7 was noted (À0.59 AE 0.8 MICS, À0.68 AE 0.6 SICS, p = 0.74). Surgically induced astigmatism (SIA) was significantly smaller in C-MICS group (DKP, À0.019 AE 0.095 versus À0.141 AE 0.219, p = 0.0038) at 1 month but not at final follow-up (DKP, 0.0005 AE 0.16 in C-MICS versus À0.057 AE 0.12, p = 0.3 Conclusions: Both techniques were equally safe with respect to intraoperative and postoperative findings. Coaxial micro-incision cataract surgery (C-MICS) was associated with less surgically-induced astigmatism (SIA) 1 month after surgery but differences were not statistically significant at final follow-up indicating a faster refractive recovery with C-MICS than with SICS.