Multifocal custom LASIK promising for hyperopic presbyopia

July 15, 2005

There has been no significant loss of BCVA or other important safety concerns.

Washington, DC-Multifocal CustomVue (VISX) LASIK is yielding promising early results in an FDA clinical trial designed to assess its efficacy and safety for the treatment of hyperopic presbyopia, said Colman R. Kraff, MD, at the annual meeting of the American Society of Cataract and Refractive Surgery.

The study was initiated at the Kraff Eye Institute, Chicago, where Dr. Kraff is director of refractive surgery. Eligible patients must be at least 40 years old, have low-to-moderate hyperopia (+0.5 to +2.0 D), and <0.75 D of astigmatism, with best-corrected visual acuity (BCVA) of 20/20 bilaterally and uncorrected visual acuity (UCVA) worse than 20/40.

They are undergoing wavefront-guided CustomVue hyperopia treatment with a target of emmetropia to correct for distance vision in the dominant eye and the multifocal CustomVue ablation in the fellow eye to correct for distance but to afford a +1.25-D near add.

Based on outcomes achieved in those individuals, the multifocal treatment so far has been associated with good refractive accuracy, rapid attainment of good near and distance vision, and high patient satisfaction with uncorrected vision for common near and distance tasks.

Patients are experiencing a little dryness initially and some early fluctuation in vision, but there has been no significant loss of BCVA or other important safety concerns, Dr. Kraff reported.

"The data are very preliminary, but encouragingly, the few patients we have treated seem to be doing extremely well after our short follow-up," he said.

The proprietary multifocal ablation pattern uses a pupil-dependent treatment. Wavefront maps are obtained with the WaveScan aberrometer and the ablation is performed with the Star S4 laser using the variable spot scanning technology to create a steepened central zone and iris registration technology to correct for cyclotorsional rotation.

Iris registration critical "The multifocal treatment will vary for each patient depending on the size of the preoperative pupil in both mesopic and photopic conditions. Because of that feature, iris registration is critically important to ensure accurate registration of the ablation and proper placement of the pupil-size-dependent central zone relative to the pupil centroid," Dr. Kraff noted.

Patients who are considered for study participation are being very carefully screened. Those who fall within the allowed tight ranges for hyperopic and astigmatic error also undergo a trial wearing a multifocal contact lens to assess their potential satisfaction after the multifocal laser correction.

"The ablation is designed to provide only +1.25 D of near add, and based on that feature, this treatment is really only for younger presbyopic patients and not for those in their late 50s or older who have a much higher add requirement for near vision," he said.