Wavefront-guided LASIK for hyperopia, presbyopia improves near vision

Spectacle dependence for daily activities was reduced at 12 months.

W. Bruce Jackson

Wavefront-guided LASIK for hyperopia and presbyopia with an aspheric ablation profile improved near vision without adversely affecting distance vision, a study found.

The procedure reduced spectacle dependence and resulted in high patient satisfaction, the study authors said.

“The bottom line is, these patients were very happy,” W. Bruce Jackson, MD, FRCSC, the corresponding author, said in an interview with Ocular Surgery News. “What we found was that those that were slightly more hyperopic and needed their reading glasses more of the time were more likely to have a good outcome. In other words, they were more satisfied, and we were able to give them more or better near vision.”

Investigators targeted binocular simultaneous uncorrected distance visual acuity of 20/25 and reading vision of J3 or better, Dr. Jackson said.

“What we found was that we could accomplish this,” he said. “We used a central near type ablation that others had tried as well. We’re able to do it using a wavefront-guided program.”

The prospective, nonrandomized multicenter clinical trial was sponsored by Abbott Medical Optics and conducted under Investigational Treatment Authorization by Health Canada. It was not designed to obtain regulatory approval.

Results were published in the Journal of Refractive Surgery.

Patients and procedures

The study included 66 eyes of 33 patients who underwent bilateral aspheric LASIK. Mean patient age was 55.1 years.

Inclusion criteria were up to 4 D of hyperopia and cylinder up to 1.5 D; age between 45 years and 70 years; addition of +1.25 D or greater at 16 inches; corrected distance visual acuity of 20/20 or better; and corrected near visual acuity of 20/25 or better.

Mean preoperative refractive error was 1.77 D sphere and 0.41 D cylinder. Mean spherical equivalent refraction was +1.97 D.

Mean preoperative Snellen corrected distance visual acuity was 20/15. Mean distance corrected near visual acuity was J5.

The Visx Star S4 and Star S4 IR excimer lasers (AMO) were used to perform all ablations. WaveScan software (AMO) was used to generate an aspheric ablation profile based on mesopic pupil size. Wavefront-guided hyperopic correction was driven by CustomVue (AMO). Minimal stromal bed thickness was 250 µm.

All patients underwent full distance refractive correction. None underwent monovision or were purposefully left with residual myopia, the authors said.

“We showed that by increasing negative spherical aberration, you improve near vision,” Dr. Jackson said. “In our study, we did not end up with these patients being myopic, whereas in some studies to create the near vision, they end up with a little bit of residual myopia and then to that you’re adding a presbyopic correction, which is really changing the spherical aberration.”

Visual and refractive outcomes were evaluated at 1 week and 1, 3, 6, 9 and 12 months. Investigators used a questionnaire to gauge patient satisfaction.

Sixty eyes of 30 patients were available for 6-month follow-up, and 50 eyes of 25 patients completed 12-month follow-up.

Outcomes and observations

Study results at 6 months showed a mean gain in distance corrected near visual acuity of 2.7 lines, with a maximum of six lines at near; no eye lost two or more lines of distance corrected near visual acuity.

At 12 months, all eyes had binocular uncorrected visual acuity of 20/25 or better and near vision of J3. Data showed the reduction in contrast sensitivity was clinically insignificant.

“There was a slight drop when you look at the contrast sensitivity, but this was really not felt to be significant,” Dr. Jackson said. “It was within the norms of a patient group of that age, so that really wasn’t a problem. The nice thing about it is that they didn’t have problems with night glare or any other symptoms like that.”

A majority of patients reported high satisfaction with visual sharpness and clarity, the authors reported.

Results showed that 100% of patients depended on spectacles preoperatively for reading, computer use and writing checks. At 6 months, spectacle dependence declined to 60% for reading, 21% for computer use and 7% for writing checks. At 12 months, spectacle dependence was 68% for reading, 48% for computer use and 28% for writing checks, the authors said.

“We were aiming for J3, but J3 isn’t the same as J1,” Dr. Jackson said. “So, for some patients, having that degree of near vision just wasn’t enough to make them totally spectacle independent. But, on the other hand, almost half required no spectacles at all and less than half required them for computer use.”

Ocular surface disease should be closely monitored preoperatively and postoperatively, especially in older female patients, Dr. Jackson said. – by Matt Hasson

Reference:

• Jackson WB, Tuan KA, Mintsioulis G. Aspheric wavefront-guided LASIK to treat hyperopic presbyopia: 12-month results with the Visx platform. J Refract Surg. 2011;27(7):519-529.

• W. Bruce Jackson, MD, can be reached at University of Ottawa Eye Institute, The Ottawa Hospital, 501 Smyth Road, Suite W-6221a, Ottawa, ON K1H 8L6, Canada; 613-737-8759; fax: 613-737-8374; email: bjackson@ohri.ca.
• Disclosure: Dr. Jackson has no relevant financial disclosures.