Mix-and-match approach maximizes refractive lens exchange outcomes

Key Points

Overland Park, KS-Bilateral implantation of an apodized diffractive IOL (AcrySof ReSTOR, Alcon Laboratories) as well as a mix-and-match approach combining the apodized diffractive lens in one eye with a zonal refractive multifocal IOL (ReZoom, Advanced Medical Optics) or an accommodating IOL (crystalens, eyeonics) in the fellow eye can provide refractive lens exchange (RLE) patients with good functional near and distance vision, said Jason Stahl, MD. In a retrospective analysis comparing the three lens combinations, however, patients with the apodized diffractive IOL implanted in one eye and the accommodating IOL contralaterally achieved the best range and quality of vision.

"We know that each of the presbyopia-correcting IOLs has its strengths, but none is perfect as each also has its weaknesses," said Dr. Stahl, a private practitioner at Durrie Vision, Overland Park, KS. "Therefore, in order to maximize outcomes and satisfy the high expectations of RLE patients, surgeons are often using a mix-and-match approach.

"The results of our retrospective analysis show each of the combinations studied is associated with high patient satisfaction and spectacle independence," he said. "Based on the benefits demonstrated, the [apodized diffractive-accommodating IOL] combination is my preferred option. However, other surgeons need to determine in their own practices what works best for them and their patients."

To evaluate outcomes using the bilateral apodized diffractive IOL and combined techniques, Dr. Stahl undertook a retrospective study including 10 RLE patients in each group. All patients had at least 3 months of follow-up, and none had undergone any enhancement to adjust the refractive outcome. Mean follow-up was longest in the bilateral apodized diffractive IOL group (about 9 months) and was 3 to 4 months in the combination groups.

Outcomes included testing of binocular UCVA using the ETDRS chart for distance, the Minnesota reading care at 32 inches for intermediate, and the ETDRS near card at 16 inches for near. Other assessments included monocular and binocular defocus curves and quality of vision, which was based on binocular contrast sensitivity testing, evaluation with the Optical Quality Analysis System (OQAS), and patient questionnaires.

The UCVA results showed binocular distance UCVA was best among patients with the apodized diffractive/refractive multifocal IOL combination implanted; 100% of those patients achieved 20/20 or better vision compared with 80% of patients with the apodized diffractive IOL implanted bilaterally and 90% of patients in the apodized diffractive/accommodating IOL group.

However, the accommodating/apodized diffractive IOL group had the best intermediate vision with 80% of patients achieving 20/40 or better compared with 30% of patients with the apodized diffractive/refractive multifocal IOL combination and only 10% of patients in the bilateral apodized diffractive IOL group. Uncorrected near vision was best in the binocular apodized diffractive IOL group where 60% of patients achieved 20/20 or better vision compared with 20% of apodized diffractive/refractive multifocal IOL patients and 30% of accommodating/apodized diffractive IOL patients.

"However, no patients wore glasses for distance or near vision tasks," Dr. Stahl said.

Results for the monocular defocus curves showed all IOLs did well at distance and near but had a drop-off for intermediate vision. Results in binocular testing showed a significant difference favoring both of the mix and match groups compared with the binocular apodized diffractive IOL group as a result of better performance in the intermediate range.

Quality-of-vision results were best for the accommodating/apodized diffractive IOL group in contrast sensitivity testing under mesopic and photopic conditions and in the OQAS testing of modulation transfer function with a 6-mm pupil and contrast values for both a 3- and 6-mm pupil.

Questionnaire results showed patients in the apodized diffractive/refractive multifocal IOL group were experiencing significantly more problems with clarity associated with halos from headlights at night compared with the accommodating/apodized diffractive IOL or bilateral apodized diffractive IOL groups as well as significantly more halos at night.

Otherwise, complaints about vision clarity at night, work, watching TV or using a computer monitor, and reading road signs at night were similarly low in all of the study groups (mean scores 1.1 to 2.7 based on a scale of 1 = no problem, 10 = disabling). There were also no significant differences between groups with regard to problems with glare or haze in any of those situations.

Dr. Stahl said it is important to achieve a refractive outcome within 0.25 D of a plano target when implanting one of these premium IOLs. As a result, surgeons offering this technology must be refractive surgeons.

"Patients with greater residual refractive error will likely be unhappy, and so surgeons need to be prepared to perform enhancements to fine-tune the astigmatic and/or spherical outcome," he concluded.