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This article belongs to the Special Issue Optical Imaging in Biomedical Engineering. Submission received: 6 May 2024 / Revised: 20 June 2024 / Accepted: 25 June 2024 / Published: 26 June 2024, This study compares a standard monofocal intraocular lens (IOL) with two rotationally asymmetric refractive multifocal IOLs, analyzing power profiles and wavefront data across three nominal powers. Tested IOLs included monofocal Acunex AN6 and multifocal AN6V (addition +1.50 D) and AN6VM (addition +3.00 D) by Teleon Surgical, at powers +10.00 D, +20.00 D, and +30.00 D. Using NIMO TR1504, power profiles, spherical aberration, and coma were analyzed. Multifocal lenses displayed an asymmetrical design, with zones for far and near vision and a central notch for far power. The multifocal AN6V and AN6VM showed neutral spherical aberration in the center, increasing to positive values, and finally achieving negative values towards the periphery. The vertical coma coefficient [Z(3:−1)] remains almost stable for the monofocal IOLs. The lower-addition multifocal IOLs induce primary vertical coma of +0.11 microns at 3 mm away from the lens center compared to +0.21 microns obtained with the high-addition lens. We can conclude that the multifocal AN6V and AN6VM lenses display an asymmetrical design. The final addition provided by these lenses depends on its nominal power. The variation of SA with optic size is more pronounced for the monofocal model, and it is dependent on the nominal power., Agencia Española de Investigación, Depto. de Optometría y Visión, Sección Deptal. de Óptica (Óptica), Fac. de Óptica y Optometría, TRUE, pub, Descuento UCM

Deflectometry is an optical technique for determining properties such as power distribution, wavefront, etc., and measurement of the optical properties of an intraocular lens can provide relevant information for clinicians. The aim of the current study was to establish a protocol for measuring lens power maps and profiles of various optical designs of intraocular lenses with a deflectometer based on the phase-shifting Schlieren principle (NIMO TR1504, Lambda-X, Nivelles, Belgium). The results are discussed with respect to accuracy and repeatability, the influence of the use of filters, and whether to consider the intraocular lens as a thin or thick lens., Agencia Estatal de Investigación (España), Depto. de Óptica, Depto. de Optometría y Visión, Fac. de Óptica y Optometría, TRUE, pub

The aim of this work was to compare an enhanced monofocal (RayOne EMV RAO200E, Rayner) and standard monofocal (RayOne RAO600C Aspheric, Rayner) intraocular lenses (IOLs) for three nominal powers (+10.00 D, +20.00 D and +30.00 D) as a function of the optical aperture diameter (pupil diameter) using a commercial Schlieren phase-shifting deflectometer NIMO TR1504 (Lambda-X, Belgium). From the wavefront maps measured by this instrument, the radial power profiles, the spherical aberration coefficients of the Zernike polynomial expansion (as a function of the optical aperture radius), and the root-mean-square (RMS) of the high-order aberrations (HOAs) were obtained and analyzed by comparing the two models. The results showed that the effective added power that could be obtained with the enhanced model depended directly on the pupil size and the power of the IOL implanted. The higher additions were achieved with the higher nominal IOL powers. The relationship between the pupil diameter, the corneal aberration of the patients and the power profile of these IOLs could have a crucial implication on the far distance and the final effective addition. However, it is important to note that these findings should be clinically validated through the implantation of these models in patients’ lenses., Agencia Estatal de Investigación (ESpaña), Depto. de Optometría y Visión, Depto. de Óptica, Fac. de Óptica y Optometría, TRUE, pub

Purpose: The scientific community has established Javal’s rule as a model linking refractive (RA) and keratometric (KA) astigmatism since its appearance more than 100 years ago. The aim was to improve the accuracy of this relationship according to subject’s age by applying the power vector analysis. Posterior corneal curvature has also been studied. Methods: The IOLMaster 700 optical biometer was used to measure the corneal thickness and the radius of curvature of the anterior and posterior corneal surfaces. Refractive error was determined by a non-cycloplegic subjective refraction process with trial lenses. Linear regression analyses were applied using J 0 and J 45 power vector components. An evaluation was carried out according to the subject’s age resulting into eight regression relationships for each astigmatic vector component for each relationship. Results: A total of 2254 right eyes from 2254 healthy subjects were evaluated. A trend towards against-the-rule astigmatism (ATR) was found with aging, both for refractive astigmatism (RA) and keratometric astigmatism (KA), with 95.2% of subjects under 20 years old having with-the-rule (WTR) KA, and only 22.8% above 79 years old. The following regression equations were found between RA and KA: J0RA = 0.73 × J0KA − 0.18 (R = 0.78) and J45RA = 0.70 × J45KA + 0.04 (R = 0.69) and between RA and total corneal astigmatism (TCA): J0RA = 0.73 × J0TCA + 0.13 (R=0.78) and J45RA = 0.70 × J45TCA − 0.06 (R = 0.68) for the whole sample, but with sensible differences among age groups, both in the slope and in the intercept. Conclusion: Ignoring the age of the subject when using Javal’s rule could lead to an error in the final cylinder calculation that would increase in high astigmatisms. Applying this new power vector approach based on subject’s age could improve the accuracy of the astigmatism prediction., Ministerio de Universidades de España, Depto. de Optometría y Visión, Fac. de Óptica y Optometría, TRUE, inpress

In recent years, the design of intraocular lenses (IOLs) has experienced a great deal of development and there is now a wide variety of designs. At the moment, some of the most interesting designs that allow for the greatest degree of innovation and customisation are lenses that combine a refractive part with a diffractive part

Purpose: Compare subjective (Rx) and objective (ObjRx) refractions outcomes with two autorefractors models and an aberrometer in eyes implanted with a hydrophobic trifocal IOL (FineVision POD F GF, Physiol, Liége, Belgium) and a hydrophilic one (FineVision POD F, Physiol, Liége, Belgium). Methods: Prospective comparative cohort study, with 100 subjects randomly assigned to either the POD F group (n = 50) or the POD F-GF group (n = 50). Postoperative eye examinations at 1-month visit included seven result sets, one for each assessment method: Rx, AR (automated refraction measured with the autorefractor KR8800), WF-P (Zernike-coefficients-based objective refraction, photopic pupil size), WF-M (Zernike-coefficients-based objective refraction, mesopic pupil size), WF-4 (Zernike-coefficients-based objective refraction, 4 mm pupil), OPD-C (automated refraction measured with the aberrometer OPD in the central pupil/photopic conditions), and OPD-M (automated refraction measured with the aberrometer OPD under mesopic conditions). Results: Mean differences between ObjRx and Rx reached statistical significance for sphere and spherical equivalent (M) only with OPD-C in the POD F-GF group. All ObjRx methods showed significant differences with Rx in the POD F group, with some values differing by more than 0.50 D (-0.58 D in M for the WF-P). Bland Altman plots showed better agreement for the astigmatic components and for sphere and spherical equivalents in both IOL groups measured with AR and OPD-M. Conclusions: None of the objective methods of refraction evaluated in this study were as reliable as the subjective refraction, irrespective of the lens material, but POD F-GF ObjRx seems to differ less with Rx than POD F ObjRx values., Depto. de Optometría y Visión, Fac. de Óptica y Optometría, TRUE, pub

Purpose: Compare subjective (Rx) and objective (ObjRx) refractions outcomes with two autorefractors models and an aberrometer in eyes implanted with a hydrophobic trifocal IOL (FineVision POD F GF, Physiol, Liége, Belgium) and a hydrophilic one (FineVision POD F, Physiol, Liége, Belgium). Methods: Prospective comparative cohort study, with 100 subjects randomly assigned to either the POD F group (n = 50) or the POD F-GF group (n = 50). Postoperative eye examinations at 1-month visit included seven result sets, one for each assessment method: Rx, AR (automated refraction measured with the autorefractor KR8800), WF-P (Zernike-coefficients-based objective refraction, photopic pupil size), WF-M (Zernike-coefficients-based objective refraction, mesopic pupil size), WF-4 (Zernike-coefficients-based objective refraction, 4 mm pupil), OPD-C (automated refraction measured with the aberrometer OPD in the central pupil/photopic conditions), and OPD-M (automated refraction measured with the aberrometer OPD under mesopic conditions). Results: Mean differences between ObjRx and Rx reached statistical significance for sphere and spherical equivalent (M) only with OPD-C in the POD F-GF group. All ObjRx methods showed significant differences with Rx in the POD F group, with some values differing by more than 0.50 D (-0.58 D in M for the WF-P). Bland Altman plots showed better agreement for the astigmatic components, and for sphere and spherical equivalents in both IOL groups measured with AR and OPD-M. Conclusions: None of the objective methods of refraction evaluated in this study were as reliable as the subjective refraction, irrespective of the lens material, but POD F-GF ObjRx seems to differ less with Rx than POD F ObjRx values., Award-winning, Postprint (author's final draft)