Serial opacification of a hydrophilic-hydrophobic acrylic intraocular lens: analysis of potential risk factors.

PURPOSE: To identify potential risk factors related to the opacification of a hydrophilic-hydrophobic acrylic intraocular lens (IOL) model.

SETTING

University Hospital Regensburg, Department of Ophthalmology, Regensburg, Germany.

DESIGN

Cross-sectional study.

METHODS

All patients with a Lentis LS-502-1 IOL implanted at the Department of Ophthalmology were identified. Existing medical records and information from the treating ophthalmologists were reviewed to determine the IOL status (clear or opacified). Potential risk factors were analyzed using binary logistic regression models.

RESULTS

A total of 223 IOLs of 199 patients were included. Sixty-seven (30.0%) opacified (calcified) IOLs were identified and compared with a control group of 156 IOLs. Statistical analyses revealed age at IOL implantation (odds ratio [OR] = 1.05, P = .012) to be associated with an increased risk of calcification. Posterior capsulotomy (OR = 0.45, P = .011) was found to have a protective influence. No other ophthalmic or systemic condition showed a significant association. Mean corrected distance visual acuity diminished significantly under opacification from 0.21 ± 0.25 logarithm of the correct minimum angle of resolution (logMAR) to 0.42 ± 0.32 logMAR (P < .001). IOL exchange in 55 of 67 cases at 45.8 ± 20.5 months after initial implantation yielded significant visual recovery (P = .001).

CONCLUSIONS

Age at implantation might be a risk factor of IOL calcification, whereas posterior capsulotomy might be a protective factor. Calcification of the LS-502-1 IOL might be caused by the interaction of 3 main factors: IOL material traits, manufacturing-associated contamination, and patients' individual factors altering intraocular ion concentrations.