Abstract
Purpose :
The purpose of this work is to predict monocular defocus curves for different intraocular lenses (IOLs) from measurements collected on an optical bench and computer simulations.
Methods :
Through-focus modulation transfer function (MTF) and phase transfer function (PTF) from -3 D to 0 D of different IOL models in an average model cornea were obtained in white light for a 3-mm pupil. The lenses measured were an aspheric monofocal (M), a monofocal that slightly extends depth of focus (sEDF), a diffractive EDF (dEDF), a refractive EDF (rEDF), a multifocal (MF) and a new range of vision (ROV) lens. The pre-clinical metrics used were the area under the MTF (MTFa) up to 50 c/mm and the weighted optical transfer function (wOTF). These preclinical metrics were fitted to clinical visual acuity (VA) from monocular defocus curves at each defocus level.
Simulated VA (sVA) values were calculated from the fit for both metrics and the different IOLs. For the same metrics and IOLs, the computer simulated VA (cVA) was calculated using 46 computer eye models with real corneas and axial lengths.
Results :
R2 of the correlation between clinical and sVA was 0.96 and 0.98 for the MTFa and the wOTF respectively. For the computer eye models, R2 was 0.93 and 0.97 for the MTFa and the wOTF respectively. sVA and cVA predicted similar outcomes: e.g. a 1-line gain for the sEDF with respect to M for intermediate and near and between 2 and 3-lines gain for the rEDF and dEDF lens for intermediate and near. cVA predicted around 1D larger range of vision over 0.20logMAR for the ROV IOL than for the EDF IOLs (range of vision was -1.9D for the rEDF and dEDF), followed by the sEDF (-1.4D) and the MF (-0.9D) that had a bimodal defocus curve. MF provided the best near VA (0.12logMAR). However, the EDF IOLs provided greater tolerance to refractive error with a higher percentage of eyes with refractive errors and good VA (similar for rEDF and dEDF, followed by sEDF). This balance was improved with the new ROV, which had the same near VA as the MF but increased tolerance.
Conclusions :
Simulated VA values obtained from optical bench and computer simulations with both metrics were overall very close to the clinical data for all lens models, with both metrics yielding comparable results. These methods can be used to evaluate the through focus performance of new IOLs and the effect of refractive errors on vision.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.