Optical characterization and through-focus performance of two advanced monofocal intraocular lenses

Abstract

Purpose To compare the refractive power profle, subjective depth-of-feld and objective optical quality of two advanced monofocal intraocular lenses (IOLs) designed to improve intermediate vision. Methods This prospective study evaluated forty-six eyes of twenty-three patients, aged 54–68 years, binocularly implanted with two monofocal enhanced intraocular lenses (IOLs), the Tecnis Eyhance and the Physiol Isopure. Subjective through-focus visual acuity curves were obtained by placing trial lenses in front of the eye while wearing its best spherical-cylindrical correction for distance. Objective optical quality was defned as the area under the modulation transfer function, calculated from the wavefront maps measured with a high-resolution aberrometer. The optical design of both lenses was compared based on their refractive power profles measured with the lenses immersed in saline solution. Results Both lenses have progressive aspherical geometries, in which the sagittal power decreases rapidly from the center to the edge of the optical zone. Mean monocular through-focus curves show a best corrected distance visual acuity of−0.02 logMAR with both lenses. Through-focus visual acuity was marginally higher for the Eyhance, with a diference of 1 letter at the defocus position of−0.5D and 3 letters between−1.0D and−2.0D. Objective assessment of optical quality revealed only a diference of about 2 points in MTF area at distance. Conclusion Both IOLs use a similar approach to improve intermediate vision. The Eyhance showed marginally better subjective performance than the Isopure at the target vergences between−1.00D and−2.00D, although these results did not reach statistical signifcance and were not replicated by the objective fndings.