Less PCO with continuous-edge IOL than interrupted- edge IOL

Researchers assessed posterior capsule opacification (PCO) in 14 patients two years after they were implanted with a Tecnis AAB00 (Abbott Medical Optics, Inc.) continuous edge single-piece acrylic IOL in one eye and an AcrySof SA60AT or SN60AT (Alcon, Inc.) one-piece acrylic IOL with an interrupted edge in the fellow eye. Posterior capsule opacification was assessed using the Evaluation of Posterior Capsular Opacification (EPCO) system on a scale of 0 (none) to 4 (severe opacity with a darkening effect).

At two years follow-up, PCO density was greater in the interrupted- edge eye, with 35 percent having an EPCO score of 3 or 4. No eye with a continuous-edge IOL had a score that high. In 13 of the 14 patients, the eye with the interrupted-edge IOL had a higher mean EPCO score than the eye with the continuous-edge IOL (0.39 versus 0.08, respectively; P =0.012).

The authors concluded that the lower level of PCO in eyes with the continuous-edge IOL was the result of the 360-degree square edge, angled haptics, increased optic-haptic space, and increased resistance to compression, all of which help position the IOL against the posterior capsule and encourage complete circumferential shrink-wrapping of the IOL by the capsule.