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

Clinical relevance: Intraocular lens dislocation usually causes severe visual symptoms and even blindness in patients. It is important for eye care practitioners to be able to identify patients susceptible to intraocular lens dislocation.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.