Evaluation of safety and stability after intraocular lens implantation using a novel material-crosslinked polyisobutylene: A preliminary study

Purpose: To evaluate the safety and stability of an intraocular lens(IOL) made of crosslinked polyisobutylene (xPIB), a novel biomaterial for new-generation foldable IOL. Setting: Eye Hospital of Wenzhou Medical University, Hangzhou, Zhejiang Province, China. Design: Prospective observational study. Methods: This was a prospective, parallel-controlled, randomised clinical study. Participants were randomly enrolled in a 1:1 ratio and underwent one-eye cataract removal with either xPIB or Acrysof (control) IOL implantation. The follow-up schedule was 1 day, 1 week, 1, 3, and 6 months, and 1 year after implantation. Various ocular biometric parameters were recorded and compared between the two groups. Results: Precisely 38 (19 per group) participants were included in this study. All surgeries were performed successfully. The xPIB IOL showed less decentration than the Acrysof IOL [0.16 (0.08,0.21) vs. 0.18 (0.12,0.21) mm] 1 week after surgery (P=0.032). The anterior capsule opening area decreased during the trial, with more shrinkage in the xPIB than in the Acrysof IOL (P<0.05 at all-time points). The anterior capsule contraction negatively correlated with the changes in postoperative aqueous depth from 1 week to 6 months (r=-0.671, P=0.002) and was uncorrelated with the changes in spherical equivalent at all-time points (P>0.05). The differences in other ocular parameters were not statistically significant between the two groups (P<0.05). Conclusions: The new xPIB IOL exhibited excellent in-the-bag stability and visual rehabilitation after cataract removal. Although the incidence was higher, the anterior capsule contraction in the xPIB group was not clinically significant and did not negatively impact vision.