Abstract: Objective To observe the decentration and tilt of intraocular lenses (IOLs) after cataract surgery in eyes that have undergone vitrectomy. Design Retrospective comparative case series. Participants Sixty-two patients (62 eyes) who underwent cataract surgery at Beijing Tongren Hospital from August 2024 to January 2025 were included. Among them, 31 patients (31 eyes) with cataract after vitrectomy were assigned to the observation group, and 31 patients (31 eyes) with age-related cataract without previous surgical history were assigned to the control group. The axial lengths of both groups were within the normal range. Methods All patients underwent IOL Master 700 and AS-OCT (CASIA 2) examinations to measure axial length, anterior segment biological parameters, and lens position parameters before cataract surgery. All patients underwent phacoemulsification and IOL implantation under topical anesthesia by the same surgeon. One month after surgery, AS-OCT was used to measure the position parameters of the IOL. Main Outcome Measures Axial length, white-to-white distance, lens thickness, equatorial diameter of the lens, preoperative lens tilt and decentration, and postoperative IOL tilt and decentration. Results There were no statistically significant differences between the observation group and the control group in axial length [24.56(23.72, 25.97)mm vs. 24.91(23.58, 26.02)mm], white-to-white distance [11.70(11.40, 12.10)mm vs.  11.60(11.50, 11.70)mm], lens thickness [4.43(4.30, 4.73)mm vs. 4.45(4.19, 4.86)mm], and equatorial diameter of the lens [10.28(9.94, 10.65)mmvs.11.60(11.50, 11.70)mm)] (P =0.916, 0.419, 0.949, 0.104). There were no statistically significant differences in preoperative lens tilt [4.30(3.50, 5.20)° vs. 4.50(3.80, 6.30)°] and decentration [0.19(0.09, 0.24)mm vs.  0.12(0.07, 0.20)mm] between the two groups (P values were 0.275 and 0.123, respectively). There were no statistically significant differences in postoperative IOL tilt [4.70(3.40, 5.10)°  vs. 4.60(3.70, 5.20)°] and decentration [0.17(0.11, 0.26)mm vs. 0.19(0.08, 0.29)mm] between the two groups (P=0.827， 0.767). There were no statistically significant differences in the changes in postoperative IOL tilt [1.10(0.40, 1.80)° vs. 0.80(0.30, 1.30)]° and decentration  [0.06(0.04, 0.12)mm vs. 0.07(0.04, 0.15)mm)] between the two groups (P=0.084, 0.693). Conclusion The short-term follow-up of this study showed that patients with normal axial length who have undergone vitrectomy and subsequently cataract surgery do not experience more significant IOL decentration and tilt.

Key words:  Vitrectomy, Cataract surgery, IOL decentration, IOL tilt