Approach creates accurate distance correction in presbyopia

For the past 3 years, his team at the University of Ottawa Eye Institute has been working on optimizing multifocal ablation profiles for the correction of presbyopia. During the American Academy of Ophthalmology annual meeting, Dr. Jackson outlined the multicenter trial's results for visual acuity, accuracy, the subjective questionnaire, safety, and topography.

Bilateral treatment All patients in the group were treated bilaterally with LASIK and the multifocal ablation profile. The group consisted of 26 eyes of 13 hyperopic, presbyopic patients. The mean age was 56, with no patients younger than 47, and 80% were women.

The longest follow-up at the time of Dr. Jackson's presentation was 12 months, at which time 10 eyes were available for analysis. However, enrollment and follow-up are ongoing.

Preoperatively the mean sphere was 1.72 D ranging up to 3.5 D, and the mean cylinder was 0.32 D with a range up to 0.75 D.

Outcomes from this study showed that 80% of eyes (n = 20) had 20/25 or better uncorrected distance visual acuity at 1 month and at 12 months 90% of eyes (n = 10) had 20/20 or better.

Looking at near visual acuity, the team assessed functional equivalency in a scheme in which J1 was a street map legend, J3 was stock quotes or a telephone book, and J5 was newspaper text.

"The results here show that 75% or more of the eyes were able to see J3, from 1 month up to 12 months," Dr. Jackson said. "Sixty percent of the eyes were able to see J1 at 12 months."

The investigators also looked at binocular near visual acuity in a subgroup of patients. After 1 month, 100% of the eyes in this group were able to see J3.

As part of their research, the team also wanted to determine whether the results were due to overcorrection or induced myopia. "When we looked at the mean spherical equivalent, only at 1 month was the mean slightly myopic. In fact, after 3 months, they were slightly hyperopic. And when you look at the distance-corrected near visual acuity after the first month, it in fact improved, such that at 12 months 70% of the eyes saw J1 or better and 100% saw J3 or better," Dr. Jackson said.

"Our target was really simultaneous 20/25 and J3, and this was accomplished in 75% of the eyes at 3 and 6 months and 80% at 12 months," he added.