To investigate the incidence of Nd:YAG-laser treatment for posterior capsular opacification (PCO) over a period of 5 years from phacoemulsification in an unselected population, comparing outcomes for three acrylic intraocular lenses (IOLs).

Retrospective longitudinal cohort study comprising 900 eyes. Three subgroups of 300 eyes, receiving the AR40, AR40e (Abbott Medical Optics, Santa Ana, California), or BL27 (Bausch & Lomb, Rochester, New York) IOL respectively, were compared. Data on patient age, gender, IOL type, dates of cataract surgery, Nd:YAG-laser treatment and/or death, and visual acuities before/after cataract surgery/Nd:YAG-laser treatment were collected from five sources: cataract operation register, patient administration system, quality control system for cataract operations, Nd:YAG-laser treatment register and clinical patient records.

216 eyes (24%) received Nd:YAG-laser treatment over a 5-year period. Statistically significant differences (p<0.001, χ² test) were found between treatment rates for the three IOLs: AR40 73 eyes (24%), BL27 91 eyes (30%) and AR40e 52 eyes (17%). Eyes of patients who died during the follow-up period had fewer treatments (23/266, 8.6%) than eyes of patients living (193/634, 30%) at the end of the follow-up period.

In comparison with a hydrophobic acrylic IOL with sharp posterior optic edge, a hydrophilic acrylic IOL was associated with almost twice the number of Nd:YAG-laser treatments over the 5-year period. The results are useful for discussing the economic long-term consequences of choosing an IOL with a design that makes PCO development more or less likely. Caution is advised when applying data from post-mortem PCO studies on living populations.