Protective membrane shows promise in reducing PCO

Investigators at John A. Moran Eye Center have found that the latest concept in the prevention of post-cataract posterior capsule opacification (PCO) – a device called a protective membrane that combats epithelial cell migration – appears promising. 

The protective membrane is made from silicone and designed for implantation inside the capsular bag with subsequent IOL implantation. The circular geometry of the membrane allows for considerable expansion of the capsular bag, a key feature as there is increasing evidence that IOLs implanted in open or expanded capsular bags help preserve capsular bag clarity.  

Investigators also experimented with a smooth and a patterned membrane design. The authors hypothesize that the pattern on the device's posterior surface would further inhibit bioadhesion of lens epithelial cells. 

Ten rabbits (20 eyes) received IOL+smooth membrane, IOL+patterned membrane or IOL alone. After 4 weeks, the mean central PCO score was 0.28 ± 0.32 (SD) in all eyes with a protective membrane and 2.08 ± 1.28 in eye with the IOL alone (P < .00001). Soemmerring ring formation and mean peripheral PCO was also significant lower in the eyes with membrane vs. IOL alone. There were no signs of inflammation or toxicity in any of the study groups. 

There were no significant differences in PCO scores between the groups with the smooth and patterned membrane, which the authors attributed to the small sample size. The authors conclude that the protective membrane allowed the capsular bag to remain expanded, thus reducing PCO when compared to implanting IOLs alone.