Extended depth-of-focus IOL withstands experimentally induced Astigmatism challenge
In a retrospective, comparative study of 3 intraocular lenses (IOLs), the extended depth-of-focus (EDOF) IOL demonstrated the highest tolerance to experimentally induced astigmatism at both distance and near, according to the results. Visual acuity (VA) was generally less affected by with-the-rule (WTR) astigmatism than against-the-rule (ATR) astigmatism, especially at distance. The researchers proposed the residual astigmatism thresholds for clinically acceptable VA reduction in all 3 IOL groups.
Previously the effect of residual astigmatism and its axis on distance and near VAs with multifocal IOLs has not been studied extensively. This study included 70 eyes of 70 participants implanted with bifocal, trifocal, or EDOF IOLs. Distance and near VAs were assessed with experimentally induced astigmatism by placing positive cylindrical lenses in increments of 0.50 D to 2.00 D at 90° and 180° axes over the best distance correction.
Results showed both distance and near VAs worsened with increasing magnitudes of experimentally induced astigmatism except in the EDOF group, in which the near VA remained within a clinically acceptable limit (within 1 line from the best corrected VA under all ranges of experimentally induced astigmatism). The EDOF group showed the highest astigmatic threshold for losing VA lines following experimental astigmatic induction at both distance and near. The distance VA was better at WTR than ATR astigmatism for all 3 groups, while the near VA was generally better at WTR than ATR astigmatism in the bifocal group, comparable between WTR and ATR astigmatism in the trifocal group, and generally better at ATR than WTR astigmatism in the EDOF group.
Reference
Chang JSM, Liu SCT, Ma NTC, Ng JCM. Comparative analysis of tolerance to experimentally induced astigmatism with three types of multifocal Intraocular Lenses. Clin Ophthalmol. 2024;18:139-149. doi:10.2147/OPTH.S429630s