Incidence and risk factors of late in the bag intraocular lens dislocation
Reviewed by Sharmina Khan

The aim of this study was to identify risk factors for late in the bag dislocation over a 21 year period. Worldwide the incidence varies from 0.05% to 3.0%. In this Swedish study they report an increase in incidence in late in the bag IOL dislocation. US studies haven’t shown any increase whereas an Australian study has shown an increase in late dislocation rates. A well known Norwegian study shows increased dislocation rates in those with pseudo-exfoliation found in higher prevalence in Scandinavian countries. Risk factor for late IOL dislocation are pseudoexfoliation glaucoma (PXF), previous vitrectomy, long axial length (>26.0mm), uveitis, connective tissue disorders, retinitis pigmentosa, glaucoma and zonular dehiscence during cataract surgery. The study identifies factors other than PXF. The data is based on 140 eyes of 123 patients compared with one case-control that didn’t have an IOL dislocation. There was a five-fold increase in the number of patients having cataract surgery performed and the pseudophakic population tripled. The median duration of pseudophakia (time from surgery to time of dislocation) increased by four years which contributed to the rising number of late IOL dislocations. The cumulative risk for IOL dislocation was 0.55% and the risk greater for those operated in the decade between 2002 and 2012 than 1992 and 2001. This is thought to be due to greater numbers of more difficult cataract extractions being completed with phakoemulsification than ever before. There was no difference in age between the study and control groups. Longer phakoemulsification time was associated with late IOL dislocation. There was no quantitative data on cataract morphology to try and correlate this with late dislocation rates. The frequency of capsular tension ring insertion was much higher in the dislocated group versus the control. 

Incidence and risk factors of late in the bag intraocular lens dislocation: Evaluation of 140 eyes between 1992 and 2012.
Dabrowska-Kloda K, Kloda T, Boudiaf S, et al.
JOURNAL OF CATARCT AND REFRACTIVE SURGERY
2015;41:1376-82.