Optical Quality of Three Multifocal Lenses.

We enjoyed reading the article by Esteve-Taboada et al.,1 but were disappointed by their interpretation of their data. Their optical model has important limitations that make it inappropriate to make broad clinical generalizations from their findings. First, the “aberration-free” eye model is highly artificial. In particular, the absence of any spherical aberration is relevant to only a small percentage of eyes undergoing cataract surgery. Our understanding is that the FineVision Micro F12 lens has a spherical aberration of -0.1 μm and the AT LISA tri lens has a spherical aberration of -0.18 μm. Because the TECNIS Symfony lens has a spherical aberration of -0.27 μm, it would be disadvantaged in this model. Second, the authors used monochromatic light at 545 nm. This again is a testing parameter that does not reflect real-world vision. As we understand it, the TECNIS Symfony lens corrects for chromatic aberration, so testing with white light would better simulate what patients might experience.2,3 Finally, more accurate appraisal of clinical performance would require evaluation of the impact of many other factors: different pupil sizes, astigmatism, other higher order aberrations, and decentration.