Abstract
This article studies the relationship between two metrics, the area under the modulation transfer function (MTFa) and the energy efficiency (EE), and their ability to predict the visual quality of patients implanted with multifocal intraocular lenses (IOLs). The optical quality of IOLs is assessed in vitro using two metrics, the MTFa and EE. We measured them for three different multifocal IOLs with parabolic phase profile using image formation, through-focus (TF) scanning, three R, G, B wavelengths, and two pupils. We analyzed the correlation between MTFa and EE. In parallel, clinical defocus curves of visual acuity (VA) were measured and averaged from sets of patients implanted with the same IOLs. An excellent linear correlation was found between the MTFa and EE for the considered IOLs, wavelengths and pupils (R2 > 0.9). We computed the polychromatic TF-MTFa, TF-EE, and derived mathematical relationships between each metrics and clinical average VA. MTFa and EE proved to be equivalent metrics to characterize the optical quality of the studied multifocal IOLs and also in terms of clinical VA predictability.
Highlights
The optical image quality of an intraocular lens (IOL) and its variation with defocus provides an essential knowledge to interpret the pseudophakic visual performance in a distance range [1,2,3,4,5]
This article studies the relationship between two metrics, the area under the modulation transfer function (MTFa) and the energy efficiency (EE), and their ability to predict the visual quality of patients implanted with multifocal intraocular lenses (IOLs)
Comparing both groups of curves, one realizes that, for a given lens and wavelength, the TF-MTFa and TF-EE curves appear to be very similar. It is straightforward for every IOL and wavelength, to obtain at each defocus position x (D) the corresponding pair of values (MTFa, EE)x and to study a possible correlation between both magnitudes
Summary
The optical image quality of an intraocular lens (IOL) and its variation with defocus provides an essential knowledge to interpret the pseudophakic visual performance in a distance range [1,2,3,4,5]. Marsack et al [6] investigate the ability of 31 scalar metrics derived from wavefront aberration maps to predict changes in the high-contrast visual acuity (VA). They found that the area under the modulation transfer function (MTFa) and the light in the bucket (LIB) [7] were among the six metrics that accounted for over 70% of the variance in VA Felipe et al [1] presented linear fits, with correlation coefficient of R2 = 0.91, between clinical VA outcomes and laboratory modulation transfer function (MTF) measurements averaged in the spatial frequency range up to the unit of decimal visual acuity With these assumptions and after refining the non-linear function that fits optical bench MTFa values with clinical VA data for a modeling IOL set (consisting of one monofocal and two bifocals), they were able to predict clinical VA at different defocus levels of patients implanted with trial IOLs of different design (two trifocals and one extended range of vision)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
