Comparison Of A Novel Trifocal Intraocular Lens To Existing Technology: Optical-Quality Assessment With Visual-Acuity Simulations

A novel CE-approved refractive-diffractive trifocal intraocular lens (IOL) has been proposed as a modality for cataract and refractive-lens-exchange patients. The IOL features a full diffractive design to produce ADD powers of 1.66D and 3.33D and correct postoperative presbyopia. The new trifocal has an aspheric aberration-neutral optic and is made of heparin-coated hydrophobic acrylic material with a refractive index of 1.49. In this study, the optical function of this lens was tested on an optical bench to provide preclinical metrics of its postoperative performance and guide future patient selection for this recent introduction to trifocal technology.      

David J. Apple Center for Vision Research, Department of Ophthalmology, University of Heidelberg, Heidelberg, Germany                                             

The optical function of the novel trifocal IOL was assessed using an optical-bench system and compared with the following models: AT LISA Tri (Carl Zeiss Meditec), Tecnis Synergy (Johnson & Johnson Vision), FineVision HP (PhysIOL) and AcrySof IQ PanOptix (Alcon). Polychromatic optical performance was assessed using white light with a photopic-eye-response filter. The area under the modulation transfer function was calculated across a defocus range from +1D to -4D and used to simulate visual acuity (VA). The IOLs’ tolerance to decentration was evaluated up to 1 mm. A polychromatic point spread function (PSF) was used to assess the light distribution and identify photic phenomena.                

Simulated distance vision was 0.00 logMAR or better for all studied IOLs. At 100 cm, the novel trifocal, AT LISA and the FineVision demonstrated a VA of 0.1 logMAR; while PanOptix and Synergy had close results, both yielding 0.12 logMAR. However, Synergy appeared more susceptible to lower defocus. From the intermediate point (approx. 80 cm), the new trifocal showed a gradual increase of VA to 0.05 logMAR (at 40 cm) - close to near VA of the other models. The impact of decentration on this new lens was minimal, but it became more apparent in IOLs featuring a higher spherical-aberration correction. Although all trifocals produced halos around the PSF, Synergy exhibited the strongest difference to the ring-background intensity. 

The novel presbyopia-correcting IOL extends the depth of focus and provides comparable optical performance to established trifocals. Since ocular imperfections may lead to the off-axis position of IOLs after implantation, the aberration-neutral design may prove advantageous in real-life conditions. Although more research is needed to characterize the photic-phenomena risk profile of this new lens, our laboratory results indicate that it may be equivalent to or better than the established models.