Diseño, realización y evaluación de implantes intracorneales difractivos multifocales

Tesis por compendio[ES] La presbicia es el error refractivo con mayor incidencia en la población debido al envejecimiento de la misma. Existen múltiples medidas para corregirla, desde lentes oftálmicas, lentes de contacto, lentes intraoculares etc¿ Actualmente, los implantes intracorneales (corneal inlays) se encuentran entre las soluciones más novedosas. Estos dispositivos se sitúan en el estroma corneal mediante una cirugía mínimamente invasiva. Existen tres implantes intracorneales comerciales cuyos mecanismos difieren entre sí. El más estudiado es el KAMRA inlay® y utiliza el efecto estenopeico para aumentar la profundad de foco. Por otra parte, Flexivue Microlens® se basa en una estructura multifocal donde el centro focaliza en lejos mientras que la periferia focaliza en cerca. Por último, Raindrop Near Vision® modifica la estructura de la córnea para aumentar el radio de curvatura de la parte central de ésta y permitir enfocar a distancias próximas. Todos ellos deben permitir el paso de nutrientes y oxígeno a través de la córnea, ya sea mediante aperturas o siendo permeables. Existe un cuarto tipo de implante intracorneal no comercial desarrollado por el Diffractive Optics Group (DiOG), el cual distribuye los micro-agujeros, que permiten el paso de nutrientes y oxígeno, en las zonas transparentes de una placa zonal de Fresnel. Además, contiene un agujero central, que actúa como estenopeico. Este dispositivo tiene como nombre Diffractive Corneal Inlay (DCI). Esta Tesis pretende modificar y optimizar los parámetros de diseño del DCI y comparar sus propiedades ópticas con otros implantes intracorneales comerciales.[EN] Presbyopia is the refractive error with the highest incidence in the population due to the aging of the population. There are many solutions to correct it, from ophthalmic lenses, contact lenses, intraocular lenses, etc... Currently the corneal inlays are among the newest solutions. These devices are placed in the corneal stroma by means of minimally invasive surgery. There are three commercial corneal inlays whose mechanisms differ from each other. The most studied is KAMRA inlay® which uses the pinhole effect to increase the depth of focus. On the other hand, Flexivue Microlens® is based on a multi-focal structure where the center focuses at distance vision while the periphery focuses at near vision. Finally, Raindrop Near Vision® modifies the structure of the cornea to increase the radius of curvature of the central part of it and allow focusing at near vision. All of them must all allow pass through to the cornea nutrients and oxygen, either by holes or being permeable. There is a fourth type of non-commercial corneal inlay developed by the Diffractive Optics Group (DiOG), which distributes micro-holes, allow the passage of nutrients and oxygen, in the transparent zones of a Fresnel zone plate. In addition, it contains a central hole, which acts as a pinhole. This device is called Diffractive Corneal Inlay (DCI). This Thesis aims to modify and optimize the design parameters of the DCI and to compare its optical properties with other commercial corneal inlays.[CA] La presbícia es l'error refractiu amb major incidència en la població degut a l'envelliment d'aquesta. Hi existeixen múltiples solucions per corregir-la, des de lents oftàlmiques, lents de contacte, lents intraoculars, etc... Actualment, els implants intracorneales comercials es troben entre les solucions mes noves. Aquests dispositius es situen a l'estroma corneal mitjançant uns cirurgia mínimament invasiva. Hi existeixen tres tipus d'implants intracorneals amb diferents mecanismes. El mes estudiat es el KAMRA inlay® i utilitza l'efecte estenopeic per augmentar la profunditat de focus. Per altra banda, Flexivue Microlens® es basa en una estructura multifocal on el centre de la lent focalitza en el focus llunyà mentre que la perifèria focalitza prop. Per últim Raindrop Near Vision® modifica l'estructura de la còrnia per augmentar el radi de curvatura de la part central d'aquesta i permetre enfocar a distàncies pròximes. Tots ells deuen permetre el pas de nutrients i oxigen a través de la còrnia, ja siga mitjançant obertures o sent permeables. Existeix un quart tipus d'implant intracorneal no comercial desenvolupat pel Diffractive Optics Group (DiOG), el qual distribueix els micro-forats, que permeten el flux de nutrients i oxigen, en les zones transparents d'una placa zonal de Fresnel. A més, contenen un forat central, que actua com estenopeic. Aquest dispositiu rep el nom Diffractive Corneal Inlay (DCI). Aquesta tesi pretén modificar i optimitzar els paràmetres de disseny del DCI i comparar les seues propietats òptiques amb altres implantes intracorneals comercials.Funding: Ministerio de Economía y Competitividad (DPI2015-71256-R); Generalitat Valenciana (PROMETEO/2019/048). D. Montagud-Martínez and V. Ferrando acknowledge the financial support from the Universitat Politècnica de València, Spain (fellowships FPI-2016 and PAID10-18, respectively).Montagud Martínez, D. (2020). Diseño, realización y evaluación de implantes intracorneales difractivos multifocales [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/153474TESISCompendi

Proposal of a new diffractive corneal inlay to improve near vision in a presbyopic eye

[EN] A new class of diffraction-based corneal inlays for treatment of presbyopia is described. The inlay is intended to achieve an improvement of the near focus quality over previous designs. Our proposal is a two-zone hybrid device with separated amplitude and phase areas having a central aperture and no refractive power. An array of micro-holes is distributed on the surface of the inlay conforming a binary photon sieve. In this way, the central hole of the disk contributes to the zero order of diffraction, and the light diffracted by the micro-holes in the peripheral photon sieve produces a real focus for near vision. We employed ray-tracing software to study the performance of the new inlay in the Liou-Brennan model eye. The modulation transfer functions (MTFs) at the distance and near foci, and the area under the MTFs for different object vergences, were the merit functions used in the evaluation. The results were compared with those obtained with previous pure amplitude designs. Additionally, image simulations were performed with the inlays in the model eye to show the good performance of our proposal in improving the quality of the near vision. (C) 2020 Optical Society of AmericaMinisterio de Economia y Competitividad, Spain (2019/048, DPI 2015-71256-R); Conselleria d'Educacio, Investigacio, Cultura i Esport, Comunitat Valenciana, Spain (PROMETEO/2019/048). Portions of this work were presented at the Optics Meeting (RIAO), the Latinoamerican Meeting in Optics, Lasers and Applications (OPTILAS), and the Mexican Optics and Photonics Meeting (MOPM) in September 2019, Diffractive corneal inlays: ray tracing analysis in a model eye . D. Montagud Martinez and V. Ferrando acknowledge the financial support from the Universitat Politècnica de València, Spain (fellowships FPI 2016 and PAID 10 18, respectively).Montagud-Martínez, D.; Ferrando, V.; Monsoriu Serra, JA.; Furlan, WD. (2020). Proposal of a new diffractive corneal inlay to improve near vision in a presbyopic eye. Applied Optics. 59(13):D54-D58. https://doi.org/10.1364/AO.383581SD54D585913Lindstrom, R. L., MacRae, S. M., Pepose, J. S., & Hoopes, P. C. (2013). Corneal inlays for presbyopia correction. Current Opinion in Ophthalmology, 24(4), 281-287. doi:10.1097/icu.0b013e328362293eCharman, W. N. (2014). Developments in the correction of presbyopia II: surgical approaches. Ophthalmic and Physiological Optics, 34(4), 397-426. doi:10.1111/opo.12129Furlan, W. D., García-Delpech, S., Udaondo, P., Remón, L., Ferrando, V., & Monsoriu, J. A. (2017). Diffractive corneal inlay for presbyopia. Journal of Biophotonics, 10(9), 1110-1114. doi:10.1002/jbio.201600320Kipp, L., Skibowski, M., Johnson, R. L., Berndt, R., Adelung, R., Harm, S., & Seemann, R. (2001). Sharper images by focusing soft X-rays with photon sieves. Nature, 414(6860), 184-188. doi:10.1038/35102526Giménez, F., Monsoriu, J. A., Furlan, W. D., & Pons, A. (2006). Fractal photon sieve. Optics Express, 14(25), 11958. doi:10.1364/oe.14.011958Montagud-Martinez, D., Ferrando, V., Machado, F., Monsoriu, J. A., & Furlan, W. D. (2019). Imaging Performance of a Diffractive Corneal Inlay for Presbyopia in a Model Eye. IEEE Access, 7, 163933-163938. doi:10.1109/access.2019.2949223Montagud-Martínez, D., Ferrando, V., Monsoriu, J. A., & Furlan, W. D. (2019). Optical Evaluation of New Designs of Multifocal Diffractive Corneal Inlays. Journal of Ophthalmology, 2019, 1-6. doi:10.1155/2019/9382467Liou, H.-L., & Brennan, N. A. (1997). Anatomically accurate, finite model eye for optical modeling. Journal of the Optical Society of America A, 14(8), 1684. doi:10.1364/josaa.14.001684Alarcon, A., Canovas, C., Rosen, R., Weeber, H., Tsai, L., Hileman, K., & Piers, P. (2016). Preclinical metrics to predict through-focus visual acuity for pseudophakic patients. Biomedical Optics Express, 7(5), 1877. doi:10.1364/boe.7.00187

Optical Evaluation of New Designs of Multifocal Diffractive Corneal Inlays

[EN] Purpose. To assess the imaging properties of two different designs of a new concept of corneal inlays whose working principle is based on diffraction. Methods. The quality of the retinal images provided by Diffractive Corneal Inlays (DCIs) was evaluated theoretically in comparison with Small Aperture Corneal Inlay (SACI). ZEMAX OpticStudio software was employed for the simulations in an eye model with different pupil diameters (3.0 mm and 4.5 mm). The employed merit functions in the analysis were the Modulation Transfer Function (MTF), the area under the MTF (MTFa), and the Point Spread Function (PSF). Comparison was made with the SACI at different defocus conditions. Results. The bifocal nature of the DCIs was demonstrated in a model eye for the first time. It was shown that the intensity of the near focus depends on the radius of the central zone. Retinal image quality of the DCI was equal to or exceeded the SACI in the majority of visual conditions as was demonstrated with simulated images. Conclusions. A new customizable type of corneal inlays has been evaluated using objective numerical simulations. Improvements in imaging of near objects and in light throughput compared with the popular small aperture inlays were demonstrated. These findings open a new technical branch of minimally invasive surgical solutions for the treatment of presbyopia.D. Montagud-Martinez and V. Ferrando acknowledge the financial support from the Universitat Politècnica de València, Spain (fellowships FPI-2016 and PAID-10-18, respectively). This work was supported in part by the Ministerio de Economia y Competitividad, Spain, (grant DPI2015-71256-R) and by the Generalitat Valenciana (Grant PROMETEO/2019/048), Spain.Montagud-Martínez, D.; Ferrando, V.; Monsoriu Serra, JA.; Furlan, WD. (2019). Optical Evaluation of New Designs of Multifocal Diffractive Corneal Inlays. Journal of Ophthalmology. 2019:1-6. https://doi.org/10.1155/2019/9382467S162019Fricke, T. R., Tahhan, N., Resnikoff, S., Papas, E., Burnett, A., Ho, S. M., … Naidoo, K. S. (2018). Global Prevalence of Presbyopia and Vision Impairment from Uncorrected Presbyopia. Ophthalmology, 125(10), 1492-1499. doi:10.1016/j.ophtha.2018.04.013Furlan, W. D., García-Delpech, S., Udaondo, P., Remón, L., Ferrando, V., & Monsoriu, J. A. (2017). Diffractive corneal inlay for presbyopia. Journal of Biophotonics, 10(9), 1110-1114. doi:10.1002/jbio.201600320Kipp, L., Skibowski, M., Johnson, R. L., Berndt, R., Adelung, R., Harm, S., & Seemann, R. (2001). Sharper images by focusing soft X-rays with photon sieves. Nature, 414(6860), 184-188. doi:10.1038/3510252

Optical performance of a new design of trifocal intraocular lens based on the Devil's diffractive lens

In this work, we propose a new diffractive trifocal intraocular lens design with focus extension, conceived to provide a high visual performance at intermediate distances. This design is based on a fractal structure known as the "Devil's staircase". To assess its optical performance, numerical simulations have been performed with a ray tracing program using the Liou-Brennan model eye under polychromatic illumination. The simulated through the focus visual acuity was the merit function employed to test its pupil-dependence and its behavior against decentering. A qualitative assessment of the multifocal intraocular lens (MIOL) was also performed experimentally with an adaptive optics visual simulator. The experimental results confirm our numerical predictions. We found that our MIOL design has a trifocal profile, which is very robust to decentration and has low degree of pupil dependence. It performs better at intermediate distances than at near distances and, for a pupil diameter of 3 mm, it works like an EDoF lens over almost the entire defocus range

Diffractive Corneal Inlays: A New Concept for Correction of Presbyopia

A new class of corneal inlays for treatment of presbyopia is described, which uses diffraction as the working principle. The inlay consists of an opaque disk with a small central aperture surrounded by an array of micro-holes that are distributed following the order of a given Fresnel zone plate having N zones. In this way, the central hole of the disk produces an extension of the depth of focus of the eye for distance vision and contributes to the zero order of diffraction, and the light diffracted by the micro-holes in the periphery produces a real focus for near vision. In our general design, the number of zones and the diameter of the central hole are free parameters that can be used to design customized devices with different addition power and near-focus intensity. Two different designs are analyzed to show this property. In the analysis, we employed a ray tracing software to study the performance of the new inlays in the two different model eyes. The results are compared with those obtained with a model of the small-aperture inlay that is currently in the market. The different merit functions used in the comparison and the image simulations performed with the inlays in the model eyes show the excellent performance of our proposal

Characterization of multifocal lenses through a virtual laboratory based on Fourier optics

[ES] En este trabajo presentamos un nuevo laboratorio virtual, desarrollado en Python, que permite la caracterización óptica de una serie de lentes multifocales bajo diferentes parámetros de configuración (esfera, cilindro, eje, diámetro de pupila, aberración esférica, ...) mediante diferentes métricas basadas en la óptica de Fourier, tales como la Función de Transferencia de Modulación (MTF), la Función de Dispersión del Punto (PSF) y la simulación de formación de imágenes de diferentes optotipos.[EN] In this paper we present a new Python developed virtual laboratory that allows the optical characterization of a series of multifocal lenses under different setup parameters (sphere, cylinder, axis, pupil diameter, spherical aberration, ...) by using different metrics based on the Fourier optics, such as the Modulation Transfer Function (MTF), the Point Spread Function (PSF) and the image forming simulation of different optotypes.Este trabajo ha sido financiado por el Ministerio de Ciencia e Innovación de España [PID2019-107391RB-I00] y por la Generalitat Valenciana (España) [PROMETEO/2019/048]. D.  M.-M. también agradece la financiación otorgada por la beca Margarita Salas del Ministerio de Universidades de España financiado por the European Union-Next Generation EU. Este trabajo ha sido desarrollado por el Equipo de Innovación y Calidad Educativa MSEL de la Universitat Politècnica de València.Ferrando Martín, V.; Montagud-Martínez, D.; Monsoriu, JA.; Remón, L.; Furlan, WD. (2023). Caracterización de lentes multifocales mediante un laboratorio virtual basado en la óptica de Fourier. Modelling in Science Education and Learning. 16(2):5-11. https://doi.org/10.4995/msel.2023.1906151116

Stereopsis assessment at multiple distances with an iPad application

[EN] We present a new application for iPad for screening stereopsis at multiple distances that allows testing up to ten levels of stereoacuity at each distance. Our approach is based on a random dot stereogram viewable with anaglyph spectacles. Sixty-five subjects with no ocular diseases, wearing their habitual correction were measured at 3 m and 0.5 m. Results were compared with a standard stereoscopic test (TNO). We found not statistically significant differences between both tests, but our method achieved higher reproducibility. Applications in visual screening programs and to design and use of 3D displays, are suggested. (C) 2017 Elsevier B.V. All rights reserved.This work was supported by the Ministerio de Economia y Competitividad and FEDER (Grant DPI2015-71256-R) and by the Generalitat Valenciana (Grant PROMETEOII-2014-072), Spain. D. Montagud acknowledges financial support from Universitat Politecnica de Valencia (PAID-01-16)Rodríguez-Vallejo, M.; Ferrando, V.; Montagud-Martínez, D.; Monsoriu Serra, JA.; Furlan, WD. (2017). Stereopsis assessment at multiple distances with an iPad application. Displays. 50:35-40. https://doi.org/10.1016/j.displa.2017.09.001S35405

A new trifocal corneal inlay for presbyopia

[EN] Corneal inlays (CIs) are the most recent surgical procedure for the treatment of presbyopia in patients who want complete independence from the use of glasses or contact lenses. Although refractive surgery in presbyopic patients is mostly performed in combination with cataract surgery, when the implantation of an intraocular lens is not necessary, the option of CIs has the advantage of being minimally invasive. Current designs of CIs are, either: small aperture devices, or refractive devices, however, both methods do not have good performance simultaneously at intermediate and near distances in eyes that are unable to accommodate. In the present study, we propose the first design of a trifocal CI, allowing good vision, at the same time, at far, intermediate and near vision in presbyopic eyes. We first demonstrate the good performance of the new inlay in comparison with a commercially available CI by using optical design software. We next confirm experimentally the image forming capabilities of our proposal employing an adaptive optics based optical simulator. This new design also has a number of parameters that can be varied to make personalized trifocal CI, opening up a new avenue for the treatment of presbyopia.This work was supported by Ministerio de Ciencia e Innovacion, Spain (Grant PID2019-107391RB-I00) and by Generalitat Valenciana, Spain, (Grant PROMETEO/2019/048). D. Montagud-Martinez and V. Ferrando acknowledge the financial support from the Universitat Politecnica de Valencia, Spain (fellowships FPI-2016 and PAID-10-18, respectively)Furlan, WD.; Montagud-Martínez, D.; Ferrando, V.; Garcia-Delpech, S.; Monsoriu Serra, JA. (2021). A new trifocal corneal inlay for presbyopia. Scientific Reports. 11(1):1-8. https://doi.org/10.1038/s41598-021-86005-8S1811

Imaging Performance of a Diffractive Corneal Inlay for Presbyopia in a Model Eye

(c) 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works.[EN] In this work we evaluated the imaging properties of the Diffractive Corneal Inlay (DCI), a novel type of corneal implant working by diffraction that we proposed for the treatment of presbyopia. ZEMAX OpticStudio software was employed for the numerical assessment, with simulations performed in a human-based eye model. In the ray tracing analysis, we used the Modulation Transfer Function (MTF), the Area under the MTF (AMTF), and the Point Spread Function (PSF). The theoretical performance of the DCI under different situations was evaluated in comparison with a commercially available pinhole based corneal inlay. Finally, real images were obtained experimentally in vitro in a model eye with inlays prototypes. The obtained results allow to state that the DCI exhibits a very high light throughput, improved imaging capabilities for far and near objects, and robustness against decentrations.This work was supported in part by the Ministerio de Economia y Competitividad under Grant DPI2015-71256-R, and in part by the Generalitat Valenciana, Spain, under Grant PROMETEO/2019/048. The work of D. Montagud-Martinez and V. Ferrando was supported by the Universitat Politecnica de Valencia, Spain, under Grant FPI-2016 and Grant PAID-10-18.Montagud-Martínez, D.; Ferrando, V.; Machado-Olivares, FJ.; Monsoriu Serra, JA.; Furlan, WD. (2019). Imaging Performance of a Diffractive Corneal Inlay for Presbyopia in a Model Eye. IEEE Access. 7:163933-163938. https://doi.org/10.1109/ACCESS.2019.2949223S163933163938

Relative Peripheral Myopia Induced by Fractal Contact Lenses

[EN] Purpose: To assess the peripheral refraction induced by Fractal Contact Lenses (FCLs) in myopic eyes by means of a two-dimensional Relative Peripheral Refractive Error (RPRE) map. Materials and Methods: This study involved 26 myopic subjects ranging from -0.50 D to -7.00 D. FCLs prototypes were custom-manufactured and characterized. Corneal topographies were taken in order to assess correlations between corneal asphericity and lens decentration. Two-dimensional RPREs were measured with an open-field autorefractor at 67 points, covering the central 60 x 30 degrees of the visual field. The bidimensional RPRE vector components: M, J(0) and J(45) of the difference between the values obtained with and without the FCLs in the eye were obtained. Additionally, the FCL-induced peripheral refraction in tangential and sagittal planes was computed along the horizontal meridian. Results: Induced by the FCLs, significant differences for all vector components were found in the peripheral retina. FCLs were decentered a mean of 0.7 +/- 0.19 mm to the temporal cornea. The two-dimensional RPRE maps manifested the FCLs decentration. In particular, M varied asymmetrically between nasal and temporal retina after fitting the FCLs with a significant increment of the myopic shift beyond 10o (p < 0.05). No correlations were found between the amount of lens decentration and the asphericity of the cornea along temporal and nasal sides. However, significant correlations were found between the corneal asphericity and vector components of the RPRE in naked eyes. FCLs produced an increasing myopic shift in tangential and sagittal power errors along the horizontal meridian. Conclusions: As predicted by ray-tracing simulations, FCLs fitted in myopic eyes produce a myopic shift of the RPRE. The two-dimensional RPRE maps show information about the lens performance that is hidden in the conventional one-dimensional meridional representations.This work was founded by Ministerio de Economía y Competitividad FEDER (Grant DPI2015-71256-R), and by Generalitat Valenciana (Grant PROMETEOII-2014-072), Spain.Rodríguez-Vallejo, M.; Montagud-Martínez, D.; Monsoriu Serra, JA.; Ferrando Martín, V.; Furlan, WD. (2018). Relative Peripheral Myopia Induced by Fractal Contact Lenses. Current Eye Research. 43(12):1514-1521. https://doi.org/10.1080/02713683.2018.1507043S151415214312Wolffsohn, J. S., Calossi, A., Cho, P., Gifford, K., Jones, L., Li, M., … Zvirgzdina, M. (2016). Global trends in myopia management attitudes and strategies in clinical practice. Contact Lens and Anterior Eye, 39(2), 106-116. doi:10.1016/j.clae.2016.02.005Huang, J., Wen, D., Wang, Q., McAlinden, C., Flitcroft, I., Chen, H., … Qu, J. (2016). Efficacy Comparison of 16 Interventions for Myopia Control in Children. Ophthalmology, 123(4), 697-708. doi:10.1016/j.ophtha.2015.11.010Walline, J. J. (2016). Myopia Control. Eye & Contact Lens: Science & Clinical Practice, 42(1), 3-8. doi:10.1097/icl.0000000000000207González-Méijome, J. M., Faria-Ribeiro, M. A., Lopes-Ferreira, D. P., Fernandes, P., Carracedo, G., & Queiros, A. (2015). Changes in Peripheral Refractive Profile after Orthokeratology for Different Degrees of Myopia. Current Eye Research, 41(2), 199-207. doi:10.3109/02713683.2015.1009634Sankaridurg, P. (2017). Contact lenses to slow progression of myopia. Clinical and Experimental Optometry, 100(5), 432-437. doi:10.1111/cxo.12584Hiraoka, T., Kotsuka, J., Kakita, T., Okamoto, F., & Oshika, T. (2017). Relationship between higher-order wavefront aberrations and natural progression of myopia in schoolchildren. Scientific Reports, 7(1). doi:10.1038/s41598-017-08177-6Atchison, D. A., & Rosén, R. (2016). The Possible Role of Peripheral Refraction in Development of Myopia. Optometry and Vision Science, 93(9), 1042-1044. doi:10.1097/opx.0000000000000979Troilo, D. (2016). The Case for Lens Treatments in the Control of Myopia Progression. Optometry and Vision Science, 93(9), 1045-1048. doi:10.1097/opx.0000000000000916Turnbull, P. R. K., Munro, O. J., & Phillips, J. R. (2016). Contact Lens Methods for Clinical Myopia Control. Optometry and Vision Science, 93(9), 1120-1126. doi:10.1097/opx.0000000000000957Rodriguez-Vallejo, M., Benlloch, J., Pons, A., Monsoriu, J. A., & Furlan, W. D. (2014). The Effect of Fractal Contact Lenses on Peripheral Refraction in Myopic Model Eyes. Current Eye Research, 39(12), 1151-1160. doi:10.3109/02713683.2014.903498Charman, W. N. (2011). Keeping the World in Focus: How Might This Be Achieved? Optometry and Vision Science, 88(3), 373-376. doi:10.1097/opx.0b013e31820b052bKee, C.-S., Hung, L.-F., Qiao-Grider, Y., Roorda, A., & Smith, E. L. (2004). Effects of Optically Imposed Astigmatism on Emmetropization in Infant Monkeys. Investigative Opthalmology & Visual Science, 45(6), 1647. doi:10.1167/iovs.03-0841Chu, C. H. G., & Kee, C. S. (2015). Effects of Optically Imposed Astigmatism on Early Eye Growth in Chicks. PLOS ONE, 10(2), e0117729. doi:10.1371/journal.pone.0117729Monsoriu, J. A., Saavedra, G., & Furlan, W. D. (2004). Fractal zone plates with variable lacunarity. Optics Express, 12(18), 4227. doi:10.1364/opex.12.004227Rodríguez-Vallejo, M., Montagud, D., Monsoriu, J. A., & Furlan, W. D. (2017). On the power profiles of contact lenses measured with NIMO TR1504. Journal of Optometry, 10(4), 265-266. doi:10.1016/j.optom.2016.10.002Plainis, S., Atchison, D. A., & Charman, W. N. (2013). Power Profiles of Multifocal Contact Lenses and Their Interpretation. Optometry and Vision Science, 90(10), 1066-1077. doi:10.1097/opx.0000000000000030Calossi, A. (2007). Corneal Asphericity and Spherical Aberration. Journal of Refractive Surgery, 23(5), 505-514. doi:10.3928/1081-597x-20070501-15Lopes-Ferreira, D. P., Neves, H. I. F., Faria-Ribeiro, M., Queirós, A., Fernandes, P. R. B., & González-Méijome, J. M. (2015). Peripheral refraction with eye and head rotation with contact lenses. Contact Lens and Anterior Eye, 38(2), 104-109. doi:10.1016/j.clae.2014.11.201THIBOS, L. N., WHEELER, W., & HORNER, D. (1997). Power Vectors: An Application of Fourier Analysis to the Description and Statistical Analysis of Refractive Error. Optometry and Vision Science, 74(6), 367-375. doi:10.1097/00006324-199706000-00019Ehsaei, A., Mallen, E. A. H., Chisholm, C. M., & Pacey, I. E. (2011). Cross-sectional Sample of Peripheral Refraction in Four Meridians in Myopes and Emmetropes. Investigative Opthalmology & Visual Science, 52(10), 7574. doi:10.1167/iovs.11-7635Osuagwu, U. L., Suheimat, M., & Atchison, D. A. (2017). Peripheral aberrations in adult hyperopes, emmetropes and myopes. Ophthalmic and Physiological Optics, 37(2), 151-159. doi:10.1111/opo.12354Verkicharla, P. K., Suheimat, M., Schmid, K. L., & Atchison, D. A. (2016). Peripheral Refraction, Peripheral Eye Length, and Retinal Shape in Myopia. Optometry and Vision Science, 93(9), 1072-1078. doi:10.1097/opx.0000000000000905Atchison, D. A. (2006). Optical models for human myopic eyes. Vision Research, 46(14), 2236-2250. doi:10.1016/j.visres.2006.01.004He, J. C. (2014). Theoretical model of the contributions of corneal asphericity and anterior chamber depth to peripheral wavefront aberrations. Ophthalmic and Physiological Optics, 34(3), 321-330. doi:10.1111/opo.12127Osuagwu, U. L., Suheimat, M., & Atchison, D. A. (2016). Mirror Symmetry of Peripheral Monochromatic Aberrations in Fellow Eyes of Isomyopes and Anisomyopes. Investigative Opthalmology & Visual Science, 57(7), 3422. doi:10.1167/iovs.16-19267Shen, G., Qi, Q., & Ma, X. (2016). Effect of Moisture Chamber Spectacles on Tear Functions in Dry Eye Disease. Optometry and Vision Science, 93(2), 158-164. doi:10.1097/opx.000000000000077