Investigational phakic IOL: examining the evidence

The AcrySof angle-supported phakic refractive IOL (Alcon) continues to offer patients with high myopia stable and accurate refractive results with excellent visual acuity (VA), according to physicians speaking at the XXIV Congress of the European Society of Cataract and Refractive Surgeons (ESCRS) in London last September.

Here we provide you with the latest efficacy and safety data from European and US FDA trials of the first single-piece, foldable AcrySof lens of its kind.

Promising European results

The preoperative mean manifest spherical equivalent (MRSE) was -11.35 D, this improved to -0.5 D at one day postoperatively, -0.79 D at six months, -0.86 D at one year and -0.88 D at five years. At five years postoperatively, the refractive predictability was met for the percentage of eyes with ±0.5 D of intended MRSE (57%) and was slightly lower for the percentage of eyes within ±1.0 D of intended MRSE (71%).

"The AcrySof lens showed excellent uncorrected visual acuity (UCVA) and best corrected visual acuity (BCVA) at five years follow-up," explained Dr Knorz. "The refraction was stable for five years, the predictability of refraction was similar to FDA guidelines and the chronic endothelial cell loss was less than FDA guidelines."

UCVA at five years was 20/20 or better in 55.6% of eyes and 20/40 or better in 88.9% of eyes. BCVA during this time was also excellent with 66.7% of eyes achieving 20/20 or better and 100% of eyes achieving 20/25 or better. There was no change in best-spectacle corrected visual acuity (BSCVA) in 55.6% of eyes and the rest gained one or more lines of BSCVA.

Endothelial corneal cell (ECC) loss was measured during the acute phase (from baseline to six months postoperatively) and the chronic phase (six months to five years postoperatively). The acute phase showed a mean ECC loss of -13.26%, which was high. This was attributed to two cases of ECC loss during surgery; one subject lost 48.8% of the cells because the lens was implanted upside down and had to be repositioned and another subject lost 29.2% of cells.

Other adverse events included one cataract that developed because of crystalline lens touch during surgery, one IOL replacement with a larger size and one LASIK procedure to correct residual astigmatism. "There were no IOL-related complications such as endophthalmitis, IOL dislocation, pupillary block, raised IOP, synechia or pupil ovalization," remarked Dr Knorz.

Combined US and European data

Combined analysis of European Phase II and III trial data with the FDA Phase I and II trial data, demonstrate the benefits of this lens in correcting high myopia at six months and one year follow-up, according to Jorge L. Alio, MD.