Small Pupils and EDOF

Intraocular lenses (IOLs) providing extended depth of focus (EDOF) using a continuous transitional focus multifocal refractive design may be better tolerated by patients with small pupils than IOLs using a central higher-order aberration (HOA) segment to extend focus depth, according to a study by Ali Nowrouzi MD.

Retrospective case series

The study evaluated 250 patients for photopic pupil size using a Pentacam (Oculus). One hundred fifty had received EDOF IOLs using central HOA designs (either Alcon Vivity or Bausch + Lomb LuxSmart), and 100 received EDOF IOLs using a continuous transitional focus design (Ophtec Precizon Presbyopic). For patients with photopic pupil size of less than 2.5 mm, visual function and patient satisfaction were assessed using a VF-14 questionnaire modified to evaluate tasks without spectacles, Dr Nowrouzi said.

Overall, 7 (2.8%) patients receiving central HOA IOLs had photopic pupils measuring less than 2.5 mm. Mean myopic refractive error was -0.50±0.25 D. Six of these patients underwent laser treatment due to dissatisfaction with uncorrected distance vision.

A total of 1-0 (4.0%) patients receiving the continuous transitional focus lenses had photopic pupils measuring less than 2.5 mm. Mean myopic refractive error was -0.25±0.25 D. None of these patients require laser treatment.

The difference in intervention rates was significant (p < 0.001), Dr Nowrouzi reported. In addition, the continuous transitional focus group scored significantly better on the VF-14.

Pupil size impact

The difference in outcomes can be explained by how small pupils interact with the various EDOF IOL designs, Dr Nowrouzi said. Small pupils affect IOLs using central HOAs more because, at 2.5 mm, about 80% of the light enters the central zone, which primarily enhances intermediate vision. The result is an increased myopic shift for distance vision.

By contrast, IOLs using continuous transitional focus have a steady, nonlinear power distribution in the central zone. Because there is no segmentation for specific near or intermediate focus, lens power is blended, offering smoother vision transitions across all distances. As a result, they are less affected by small pupil size, Dr Nowrouzi explained.

In conclusion, Dr Nowrouzi noted that in patients with photopic pupil size of less than 2.5 mm, continuous transitional focus IOLs produce less myopic shift and patient dissatisfaction than IOLs with a central HOA segment.

“It’s important to evaluate pupil size before surgery, mainly with EDOF lenses with the central segment, to prevent problems,” he advised.

Dr Nowrouzi spoke at the 2025 ASCRS annual meeting in Los Angeles.

Ali Nowrouzi MD, FEBOS-CR, FICO, FACS, FWCRS is an ophthalmologist in private practice at Hospital Quironsalud, Marbella, Spain. dralinoroozi2020@gmail.com