Accommodating IOL improves vision for high refractive errors inanalysis

June 1, 2006

San Francisco-The crystalens accommodating IOL (eyeonics)improved visual outcomes "dramatically" in a study of patients withhigh myopia or high hyperopia. The IOL achieved similar near visualacuity levels in both patient groups, reported Harvey Carter, MD,at the annual meeting of the American Society of Cataract andRefractive Surgery.

Dr. Carter and colleagues performed a retrospective analysis of the accommodating outcomes in patients who had the crystalens implanted over a 2-year period.

The patients who were included in the study were selected from a consecutive series of patients who had received more than 1,200 implanted lenses. They had very high degrees of myopia (defined as exceeding –5.0 D) or hyperopia (defined as exceeding +3.0 D) or they had very high lens powers (defined as ranging from 23.5 and 27.5 D) or very low lens powers (defined as ranging from 16.5 and 19.5 D), explained Dr. Carter, who is in private practice in Dallas. All patients had to have had at least 1 year of clinical follow-up to be included in the analysis.

The investigators looked at the near vision through the distance correction in eyes that had the IOL implanted 1 year previously.

"We had a matched series of 37 eyes with a long axial length and 37 eyes with a short axial length. The long axial length ranged from 24.34 and 26.6 mm, and the short axial length ranged from 21.0 to 22.79 mm," Dr. Carter said.

The results indicated that in the myopic eyes, the near vision through the distance correction was J1 and better in 21% of the patients, J2 and better in 51%, and J3 and better in 91%, according to Dr. Carter.

When the investigators compared the results in the myopic eyes with results in the hyperopic eyes, they found that 21.6% had J1 and better, 48% had J2 and better, and 89% had J3 and better, Dr. Carter recounted.

A second comparison was then made between groups of lens implants with very low and very high power. There were 41 eyes in the low-power group and 61 eyes in the high-power group. "This comparison also showed similar results with both the low-power and the high-power lenses achieving J1 and better vision in 22% and 23% of eyes, respectively, 53% and 49% achieving J2 and better vision, and 85% and 88% achieving J3 and better vision," Dr. Carter reported.

Dramatic improvement

In the final comparison, the investigators went on to evaluate the patients with high degrees of hyperopia and myopia to determine the accommodation provided by the crystalens. Before the patients with high hyperopia had the crystalens implanted, the visual acuity levels were "quite poor, as expected," he said. "After implantation in this group, the improvement in visual acuity was dramatic. All of the patients had uncorrected distance visual acuity and near visual acuity that were about 20/40; when compared with the 20/20 range, 30% of patients had 20/20 and better in distance visual acuity and 38% had 20/20 at near."