Visual performance of an extended depth of focus intraocular lens for treatment selection
Thomas Kohnen1, Myriam Böhm2, Eva Hemkeppler2
1Department of Ophthalmology, Goethe University, Frankfurt am Main, Germany. kohnen@em.uni-frankfurt.de.
Purpose:
To evaluate the visual performance of an extended depth of focus (EDOF) intraocular lens (IOL) for patient selection.
Methods:
This prospective non-comparative case series evaluated fifty-two eyes (26 patients) after bilateral implantation of the Tecnis Symfony IOL. Exclusion criteria were previous ocular surgeries, corneal astigmatism of >1.5 diopter, and ocular pathologies or corneal abnormalities. Uncorrected (UCVA) and distance-corrected (DCVA) visual acuity (VA) in 4 m, 80 cm, 60 cm and 40 cm (logMAR), defocus curve, contrast sensitivity (CS) and a questionnaire on subjective quality of vision (QoV) were assessed after 3 months.
Results:
UCVA was -0.02 ± 0.071 logMAR at 4 m, 0.01 ± 0.077 logMAR at 80 cm, 0.08 ± 0.187 logMAR at 60 cm and 0.22 ± 0.153 logMAR at 40 cm. Defocus curve testing showed a flat VA range from 0.00 to -1.50 D (-0.05-0.02 logMAR). At near distance from -2.0 to -2.5 D a dip of DCVA was observed (0.14-0.28 logMAR). CS under photopic and mesopic conditions without and with glare was 1.56 logCS, 0.86 logCS, 0.78 logCS, respectively. Spectacle independence was achieved in 100% for distance and intermediate vision and 71% of patients at near distance.
Conclusion:
This EDOF IOL provides excellent intermediate and far (<0.1 logMAR) and acceptable near UCVA (<0.3 logMAR). Defocus curve testing confirmed an EDOF between far and intermediate distance and showed a dip at near distance. It provides good QoV, CS, high spectacle independence, perception of few optical phenomena, and particularly good night-driving capabilities.
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