We are pleased by the interest elicited by our work.1 To deal with a new intraocular lens (IOL) implies several considerations that cannot be summarized in only 1 preliminary study. Our main goal in this publication was to compare the clinical outcomes of this new monofocal IOL, Tecnis Eyhance ICB00, to a well-known monofocal aspheric IOL, TECNIS ZCB00.1 The 2 IOLs share the same material and platform and the same chromatic aberration and spherical aberration (SA) (−0.27 μm for 6 mm aperture).2 The Tecnis Eyhance IOL increases depth of focus due to a higher-order aspheric anterior surface with a continuous and localized increase in power from the periphery to the center of the IOL. This is a fundamentally different approach than using SA to extend the depth of focus. Primarily, SA affects the power by a factor of r2, where r is the radius of the pupil. It is for this reason that the effects of primary SA are heavily noticeable for larger pupil sizes, with an increase in the depth of focus and decrease in distance vision quality. This was confirmed by a preclinical study based on clinically relevant metrics, which compared the outcomes provided by TECNIS Eyhance IOL with monofocal IOLs with different aspheric designs and different levels of SA and chromatic aberration.3,4 While TECNIS Eyhance IOL provided improvement in intermediate vision and maintained the distance image quality of an aspheric monofocal IOL, independently of the pupil size, the spherical IOL demonstrated a pupil-dependent behavior: it improved intermediate simulated vision and decreased distance image quality for large pupils, whereas, for small pupils, its performance was similar to an aspheric IOL.4 Therefore, because the depth of focus is not increased through a modification of the SA of the Eyhance IOL, we do not expect that eventual corneal SA and pupil size differences between the 2 groups of patients would affect the outcomes of our study, as suggested by Vamosi and Nemeth.1 We also think that, in a preliminary study, the comparison of 2 IOLs of the same platform adds more value than the comparison of IOLs with different designs and materials. Nevertheless, the suggestion to compare the intermediate vision outcomes of Tecnis Eyhance IOL with those of other monofocal IOLs such as SA-free aspheric IOLs is intriguing and would merit future studies. Regarding the remark about mesopic contrast sensitivity, we clearly stated in the discussion of our article, “in future studies, it could be interesting to compare the mesopic contrast sensitivity between the Eyhance ICB00 IOL and the ZCB00 IOL” and with other monofocal IOLs.1 Of interest, the mesopic contrast sensitivity is a well-known strength of the Tecnis IOL platform.5 We agree that further investigations are necessary to assess whether the new approach of the Tecnis Eyhance IOL represents a step forward in investigating the still little-explored field of intermediate vision.
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