The study was done to assess the effect of prior myopic ablations on the optical performance of a trifocal diffractive IOL and a novel EDOF diffractive design.
The novel XACT Mono-EDOF ME4 diffractive IOL (Santen Pharmaceutical) and the trifocal diffractive FineVision IOL (PhysIOL) were analyzed standing alone and combined with a simulated myopic corneal ablation. The optical quality of the IOLs in both situations was evaluated with the PMTF optical bench (LAMBDA-X). The through-focus modulation transfer function (MTF) curves and the MTF at three different focal points (+0.50, 0.00, and −0.50 diopters [D]) were recorded.
The through-focus MTF curves showed three differentiated peaks for the trifocal IOL and two overlapped peaks for the EDOF IOL. The presence of simulated myopic corneal ablations induces a −0.50 D shift on the overall through-focus curves and softens the multifocal properties of both lenses by decreasing the variations through focus of the MTF. For the analysis of the lenses standing alone, the highest MTF values were obtained for an object vergence of 0.00 D. For a simulated myopic corneal ablation, both IOLs showed better optical quality results at −0.50 D.
The conclusion of the study was that the trifocal IOL provides better optical quality at far and near distances when analyzed alone. The EDOF IOL optical properties are more stable when a myopic ablation is introduced. Preoperative calculations of both lenses should consider that prior myopic corneal ablations induce a −0.50 D shift on their far peak quality.