MAR 18, 2021
Researchers compared patient outcomes and satisfaction of different strategies for implantation of the extended range-of-vision IOL (Tecnis Symfony).
This was a single-center, prospective, observational nonrandomized comparative study comprising 206 eyes. Researchers divided participants into 3 groups based on lifestyle and near visual demands: bilateral Symfony IOL, mix-and-match Symfony IOL with bifocal +3.25 D IOL, and Symfony IOL with bifocal +4.0 D IOL. They evaluated binocular uncorrected visual acuity for distance, intermediate and near vision, along with subjective visual perception and satisfaction at 1 week and 1 and 3 months postoperatively.
Uncorrected visual acuity for distance, intermediate and near vision were similar across groups. There were no differences in contrast sensitivity under low and high luminance conditions. In the bilateral group, glare on image perception reduced contrast sensitivity for small target sizes. In addition, bilateral implantation lead to more frequent photic phenomena than the mix-and-match combinations.
The major limitation to this study may be that the target refraction for the bilateral implantation arm was mild myopia to achieve better near uncorrected vision. The remaining ametropia could have led to an increase in the photic phenomena.
This is potentially a disruptor to the guide for premium IOL selection in the United States. It makes logical sense that implanting the same IOL in each eye would yield the best results; this has always been the rule of thumb in cataract surgery. This data disputes prior thinking and shows that alternative technologies in each eye could mitigate unwanted side effects. Most surgeons have been able to achieve good distance, intermediate and near visual acuity with premium IOLs, assuming they hit the intended spherical and cylindrical target. However, the unwanted visual phenomena are real and true hindrances to the further adoption of these technologies. If this data holds true, then we may have more satisfied, spectacle-independent patients.