Comparison of posterior capsule opacification rates between hydrophilic and hydrophobic single-piece acrylic intraocular lenses.

Purpose: To determine the effect of intraocular lens (IOL) material on the development of posterior capsule opacification (PCO) at 1 year.

Setting: Department of Ophthalmology, St. Thomas' Hospital, London, United Kingdom.

Methods: One hundred six eyes of 53 patients with bilateral cataract and no other ocular comorbidity were prospectively randomized to receive a hydrophobic acrylic or hydrophilic acrylic single-piece IOL in the first eye to have surgery. The alternate IOL was implanted in the fellow eye 4 to 6 weeks later. All surgery was performed by a single surgeon. Postoperative follow-up was 1 day, 1 and 6 months, and 1 year. At each visit, the best corrected high- and low-contrast visual acuities were assessed and a high-intensity digital retroillumination photograph was taken. Posterior capsule opacification was assessed from the digital images by a single operator using a dedicated software program and calculated as the percentage area of opacified capsule.

Results: One year postoperatively, the median percentage area of PCO was 50.3% in the hydrophilic IOL group and 4.9% in the hydrophobic IOL group (P<.001). The difference in PCO was not accounted for by loss of contact between the capsulorhexis and IOL surface. Further analysis showed that lens epithelial cells tended to invade the posterior capsule at the haptic-optic junction. This was more marked in the hydrophilic IOL group.

Conclusions: The rate of PCO was significantly higher with the hydrophilic IOL. However, the results cannot be attributed to the IOL material alone as they show the importance of both IOL material and design.