Risk factors of intraocular lens dislocation following routine cataract surgery: a case-control study

Background: To investigate the risk factors of intraocular lens dislocation following routine cataract surgery. Methods: This retrospective case-control study included patients diagnosed with intraocular lens dislocation between January 2007 and March 2018. Controls matched to the cases by age and time of routine cataract surgery in a ratio of 3:1 were randomly selected from patients without intraocular lens dislocation. The medical records of the patients were reviewed and analysed. Independent t-test, chi-square test, and logistic regression analysis were employed to identify risk factors of intraocular lens dislocation. Results: In total, 127 cases (with intraocular lens dislocation) and 381 controls (without intraocular lens dislocation) were evaluated. Among cases, the proportion of men was significantly higher than that of women (p = 0.012). High myopia was significantly associated with all types of intraocular lens dislocation; it was also a risk factor for in-the-bag intraocular lens dislocation. Lens subluxation was significantly associated with the in-the-bag and late intraocular lens dislocations. Intraoperative and post-operative vitrectomy, rather than pre-operative vitrectomy, were associated with intraocular lens dislocation. Post-operative trauma was significantly associated with in-the-bag intraocular lens dislocation; pre-operative and post-operative trauma were significantly associated with out-of-the-bag intraocular lens dislocation. Male sex (odds ratio (OR) = 2.996, p = 0.006), pre-operative trauma (OR = 7.861, p = 0.014), high myopia (OR = 11.268, p < 0.001), and lens subluxation (OR = 13.431, p = 0.018) were the risk factors of intraocular lens dislocation. Conclusion: Male sex, pre-operative trauma, high myopia, and lens subluxation were the main predisposing factors for intraocular lens dislocation in Chinese Han population.