Understanding the Real Effect of the High-Order Aberrations after Myopic Femto-Lasik

In this work we try to understand the real effect of increase in aberrations after Femto-LASIK surgery on the patient’s final visual quality, specifically when the visual acuity measurement is considered. A clinical study with 37 eyes of 20 patients that underwent myopic Femto-LASIK surgery and different personalized eye model simulations were carried out. In clinical study, correlations between pre- and postoperative parameters with visual acuity were analysed. Eye simulations (based on real data) provided simulations of vision quality before and after surgery. Our main results showed a significant increase in aberrations was obtained after surgery; however, no differences were found between the preoperative corrected distance visual acuity (CDVA) and the postoperative uncorrected distance visual acuity (UDVA). This absence of differences in visual quality could be explained by performing different simulations on three eyes that would cover most of the possible clinical situations. Simulations were implemented considering a pupil size of 2.5 mm and the personalized data of each patient. Results showed that final visual acuity (VA) change are determined by the final high-order aberrations (HOAS) and their increase after surgery but measured under photopic conditions. In conclusion, customized analysis of higher-order aberrations in scotopic pupils better predicts patient visual acuity after Lasik surgery.This work was supported by the “Generalitat Valenciana” of Spain (project AICO/2021/130)

Optical Modeling of Schematic Eyes and the Ophthalmic Applications

The objectives of this dissertation are to advance and broaden the traditional average eye modeling technique by two extensions: 1) population-based and personalized eye modeling for both normal and diseased conditions, and 2) demonstration of applications of this pioneering eye modeling.The first type of representative eye modeling can be established using traditional eye modeling techniques with statistical biometric information of the targeted population. Ocular biometry parameters can be mathematically assigned according to the distribution functions and correlations between parameters. For example, the axial dimension of the eye relates to age, gender, and body height factors. With the investigation results from the studies of different population groups, population-based eye modeling can be established. The second type of eye model includes the optical components of the detailed corneal structure. Many of these structures, especially the corneal topography and wavefront aberration, are measured directly from the human eye. Therefore, the personalized eye models render the exact clinical measure and optical performance of the eye. In a sense, the whole eye, other than the identity of the individual, is quantified and stored in digital form for unlimited use for future research and industrial applications. The presentation of this dissertation is: Chapter 1 describes the background of the research in this area, the introduction of eye anatomy, and the motivation of this dissertation work. In Chapter 2, a comprehensive review of the contemporary techniques of measuring ocular parameters is presented and is followed by the review of literature and then the statistical analysis of the ocular biometry parameters. The goal of this chapter is to build a statistical base for population-based schematic eye modeling research. The analysis includes the investigation of the correlations between ocular parameters and ocular refraction, subject age, gender, ethnicity, and accommodation conditions. In Chapter 3, the tools and methods that are used in our optical eye modeling are introduced. The operation of the optical program ZEMAX is discussed. The detail of the optical eye modeling procedure and method of optical optimization, which is utilized to reproduce desired clinical measurement results, are described. The validation functions, which will be used to evaluate the optimization results, are also addressed. Chapter 4 includes the discussion of the population-based eye modeling and the personalized eye modeling. With the statistical information and the clinical measurements presented in Chapter 2 and the computation method described in Chapter 3, the two types of eye modeling technologies are demonstrated. The procedure, difficulty, and validation of eye modeling are included. The considerations of optical opacities, irregular optical surface, multiple reflection, scattering, and tear film breakup effects are discussed and the possible solutions in ZEMAX are suggested. Chapter 5 presents eye modeling applications of the simulations of ophthalmic instrument measurements. The demonstrated simulation results are retinoscopy and photorefraction. The simulation includes both normal eye model and diseased eye model. The close conformity between the simulation results with the actual clinical measurements further validates the eye modeling technique. The ophthalmic simulation application provides the potential for medical training and instrument development. The summary of the dissertation is given in Chapter 6

Simulação de acomodação e aberrações de baixa ordem do olho humano usando árvores de coleta de luz

In this work, we present two practical solutions for simulating accommodation and loworder aberrations of optical systems, such as the human eye. Taking into account pupil size (aperture) and accommodation (focal distance), our approaches model the corresponding point spread function and produce realistic depth-dependent simulations of low-order visual aberrations (e.g., myopia, hyperopia, and astigmatism). In the first solution, we use wave optics to extend the notion of Depth Point Spread Function, which originally relies on ray tracing, to perform the generation of point spread functions using Fourier optics. In the other technique, we use geometric optics to build a light-gathering tree data structure, presenting a solution to the problem of artifacts caused by absence of occluded pixels in the input discretized depth images. As such, the resulting images show seamless transitions among elements at different scene depths. We demonstrate the effectiveness of our approaches through a series of quantitative and qualitative experiments on images with depth obtained from real environments. Our results achieved SSIM values above 0.94 and PSNR above 32.0 in all objective evaluations, indicating strong agreement with the ground-truth.Neste trabalho, apresentamos duas técnicas de simulação de acomodação e aberrações de baixa ordem de sistemas ópticos, tais como o olho humano. Nossos algoritmos lançam mão de determinadas informações, tais como o tamanho da pupila e a acomodação (distância focal), com o objetivo de modelar a função de espalhamento pontual (point spread function) do sistema, resultando na produção de simulações realistas de aberrações de baixa ordem (p.e., miopia, hipermetropia e astigmatismo). Nossas simulações levam também em consideração as distâncias dos objetos que compõem a cena a fim de aplicar o borramento apropriado. A primeira técnica estende o conceito de Função de Espalhamento Pontual com Profundidade (Depth Point Spread Function), originalmente construída mediante o traçado de raios (ray tracing), que passa então a ser gerada por meio de métodos da óptica de Fourier. A segunda técnica, por sua vez, utiliza-se da óptica geométrica para construir uma estrutura de dados em forma de árvore. Esta árvore é então utilizada para simular a propagação da luz no ambiente, gerando os efeitos de borramento esperados, e de quebra soluciona o problema de artefatos visuais causados pela ausência de informação na imagem original (provocada pela oclusão parcial entre elementos da cena). Nós demonstramos a efetividade de nossos algoritmos por meio de uma série de experimentos quantitativos e qualitativos em imagens com profundidade obtidas de ambientes reais. Nossos resultados alcançaram valores de SSIM superiores a 0,94 e valores de PSNR superiores a 32,0 em todas as avaliações objetivas, o que indica uma expressiva concordância com as imagens de referência

Aberraciones cromáticas, monocromáticas y diseños multifocales: interacción e impacto en la visión

Tesis inédita de la Universidad Complutense de Madrid, Facultad de Óptica y Optometría, leída el 21/01/2021An important part of the information that we receive from the world is through the sense of vision: the eye projects images on the retina, which transforms them into nerve impulses that reach the neuronal cortex, where these impulses are interpreted. However, the images projected onto the retina are not perfect, as they are affected by diffraction, scattering, and aberrations, which degrade contrast and decrease the resolution limit of the eye. To understand the effect of aberrations on vision, it is necessary to develop technologies and experiments that allow objectively and subjectively assess their interaction. In this sense, Adaptive Optics (AO) has played an important role in increasing our knowledge about the neural processes of vision, since AO can be used to measure, correct and induce aberrations. Understanding what role aberrations play and what their impact is on vision will help to develop better correction designs for the eye. The manipulation of the wavefront using AO also allows to induce a certain visual correction, so it can be used as a basis for visual simulators. As AO allows studying a new lens design or comparing across different lens designs even before they are manufactured, this is an excellent tool to test and improve optical corrections before they are implanted in the eye of a patient. Different technologies including deformable mirrors (DM), spatial light modulators (SLM), or temporal multiplexing by an optotunable lens (SimVis), are currently being validated and launched into the clinical practice. In this thesis, AO technologies have been implemented and used both to study the effect of aberrations and to cross-validate different simulator modalities...Una importante parte de la información que recibimos del mundo lo hacemos a través del sentido de la visión: el ojo proyecta las imágenes en la retina, la cual las transforma en impulsos nerviosos que llegan hasta el córtex neuronal, donde se interpretan estos impulsos. Sin embargo, las imágenes proyectadas en la retina no son perfectas, ya que están afectadas por la difracción, la dispersión y las aberraciones, que degradan el contraste y reducen el límite de resolución del ojo. Para entender el efecto de las aberraciones en la visión es necesario desarrollar tecnologías y experimentos que permitan valorar objetiva y subjetivamente su interacción. En este sentido, la Óptica Adaptativa (AO) ha jugado un papel importante en el incremento de nuestro conocimiento acerca de los procesos neuronales de la visión, ya que la AO se puede utilizar para medir, corregir e inducir aberraciones. Comprender qué papel juegan las aberraciones y cuál es su impacto en la visión, ayudará a desarrollar mejores diseños de corrección para el ojo, sin embargo, aún no se entiendo completamente. La manipulación del frente de onda mediante AO permite, además, inducir una cierta corrección visual, por lo que se puede utilizar como base de simuladores visuales. Estudiar un nuevo diseño o comparar varios diseños entre ellos antes incluso de que sean fabricados, plantea la AO como una excelente herramienta para probar y mejorar una corrección antes de que sea implantada. Para ello, diferentes tecnologías como los espejos deformables, los Moduladores Espaciales de Luz (SLM), la multiplexación temporal inducida por una lente optoajustable (SimVis), están siendo en la actualidad validados y lanzados a la práctica clínica. En esta tesis se ha utilizado la AO tanto para estudiar el efecto de las aberraciones como comparar diferentes simuladores visuales...Fac. de Óptica y OptometríaTRUEunpu

Augmented reality fonts with enhanced out-of-focus text legibility

In augmented reality, information is often distributed between real and virtual contexts, and often appears at different distances from the viewer. This raises the issues of (1) context switching, when attention is switched between real and virtual contexts, (2) focal distance switching, when the eye accommodates to see information in sharp focus at a new distance, and (3) transient focal blur, when information is seen out of focus, during the time interval of focal distance switching. This dissertation research has quantified the impact of context switching, focal distance switching, and transient focal blur on human performance and eye fatigue in both monocular and binocular viewing conditions. Further, this research has developed a novel font that when seen out-of-focus looks sharper than standard fonts. This SharpView font promises to mitigate the effect of transient focal blur. Developing this font has required (1) mathematically modeling out-of-focus blur with Zernike polynomials, which model focal deficiencies of human vision, (2) developing a focus correction algorithm based on total variation optimization, which corrects out-of-focus blur, and (3) developing a novel algorithm for measuring font sharpness. Finally, this research has validated these fonts through simulation and optical camera-based measurement. This validation has shown that, when seen out of focus, SharpView fonts are as much as 40 to 50% sharper than standard fonts. This promises to improve font legibility in many applications of augmented reality

Modeling the effects of eye shape in peripheral refraction and myopia progression

PhD Thesis in Sciences - Specialty in PhysicsMyopia affects approximately 25% of the World population, being a public health concern due to the socioeconomic impact and to the risk of vision loss related to other co-morbidities. If current trends continue, half the world’s population (almost 5 billion) will be short-sighted in just over three decades, with one-fifth of those expected to have a significantly increased risk of blindness. Clinical evidence from animal models and human clinical trials seems to indicate that the peripheral refraction pattern plays an important role in the regulation of eye growth. Lower progression rates have been reported over the last years in myopic children wearing orthokeratology (ortho-k) or special design contact lenses, when compared with those wearing traditional ophthalmic lenses. To date, the only justification for this effect seems to lie in the significant myopization effect induced by these alternative forms of correction beyond the foveal area, but despite the moderate results obtained researcher’s still lack knowledge of the exact mechanism behind this effect and why does it work better in some subjects than others. In this thesis a frame work was developed to model the possible impact of the eye’s posterior shape and the optical changes produced by ortho-k in myopia progression. Optical modeling and biometric eye length measures were used to calculate the retinal contour in 55 myopic subjects, with an accuracy of tenths of a micron. The results show that there is large inter-subject variability in the shape of the posterior pole, even among subjects with similar refractive errors. An exhaustive characterization of the ortho-k cornea was also conducted to analyze the main morphological, topographical and optical changes induced by these treatments and their possible implications in the peripheral refractive error and accommodative response. The results suggest that the reported effects in the retention of eye growth, supposedly due to the peripheral myopization produced by ortho-k treatments, might be dependent on pupil size. Optical quality analysis revealed that although the increase in positive spherical aberration is the main cause of the loss of retinal image quality in the unaccommodated eye after ortho-k, it also seems to have a positive effect, as it extends the depth of field of the eye and may contribute to a better image quality in subjects with accommodative lag during high contrast near vision tasks.A actual prevalência mundial da Miopia (25%) é já considerada um problema de saúde pública devido ao impacto sócio-económico e ao risco de perda de visão relacionada com outras co-morbidades. Se as tendências actuais se mantiverem, metade da população mundial (quase 5 mil milhões) será míope daqui a pouco mais de três décadas, e cerca de um quinto deverá ter um aumento significativo do risco de cegueira. Evidências clínicas baseadas em modelos animais e ensaios clínicos com pacientes humanos parecem indicar que o padrão da refracção periférica desempenha um papel importante na regulação do crescimento axial do olho. Níveis mais baixos de progressão têm sido reportados ao longo dos últimos anos em grupos de crianças míopes corrigidas com ortoqueratologia (orto-k) ou lentes de contacto com geometrias especiais, em comparação grupos de controle compensados com lentes oftálmicas tradicionais. Até à data, a única justificação plausível para estes resultados parece residir no efeito miopização periférica induzido por essas formas alternativas de correção para além da área foveal, mas apesar dos resultados moderados obtidos ainda falta conhecimento do exacto mecanismo por trás deste efeito e porque o efeito é maior em alguns indivíduos que em outros. Nesta tese foi desenvolvido um quadro de trabalho com o objectivo de modelizar o possível impacto da forma do polo posterior do olho e a das alterações estruturais induzidas pela ortoqueratologia na progressão da miopia. O contorno da retina de 55 indivíduos míopes foi calculado com recurso a modelização óptica e medidas biométricas do comprimento do olho, com uma precisão de décimos de micras. Os resultados demonstram que existe uma grande variabilidade inter-individual na forma do pólo posterior do olho, mesmo entre indivíduos com erros refractivos semelhantes. Foi também realizada uma caracterização exaustiva da córnea pós orto-k, com o objectivo de analisar as principais alterações morfológicas, topográficas e ópticas induzidas por estes tratamentos e as suas possíveis implicações no erro refractivo periférico, assim na resposta acomodativa. Os resultados sugerem que os relatos de uma menor taxa de progressão da miopia em olhos tratados com ortok, supostamente devido à miopização periférica produzida por estes tratamentos, pode ser dependente do tamanho da pupila. A análise da qualidade óptica revelou que, embora o aumento da aberração esférica positiva após orto-k seja a principal causa da diminuição da qualidade da imagem retiniana no olho desacomodado, também aparenta ter um efeito positivo na extensão da profundidade de campo, o que poderá contribui para um aumento da qualidade da imagem retiniana em indivíduos com atraso acomodativo durante tarefas de alto contraste em visão próxima

Aerospace Medicine and Biology: A continuing supplement 180, May 1978

This special bibliography lists 201 reports, articles, and other documents introduced into the NASA scientific and technical information system in April 1978

Biometric measurements in the crystalline lens: applications in cataract surgery

En esta tesis, hemos desarrollado una nueva metodología para medir el desalineamiento de la IOL implantada en pacientes con cirugía de cataratas a partir de imágenes de OCT en-face del segmento anterior. También hemos cuantificado la forma y la topografía 3D del cristalino del ojo in vivo, sus propiedades ópticas y sus cambios con la anterior y posterior del cristalino, y cambios estructurales con la edad. La metodología de OCT cuantitativa y modelos de ojo personalizados en pacientes han sido validados en pacientes operados de cirugía de cataratas, mediante comparaciones de las aberraciones simuladas y medidas en los mismo pacientes, y han permitido comprender la contribución relativa de los factores ópticos geométricos y quirúrgicos relacionados con la calidad de la imagen, como la identificación del centrado óptimo de la IOL. Estos son clave en los cálculos avanzados de la potencia de la IOL, la optimización de la selección individual o diseño de IOLs personalizados que puedan proporcionar una solución visual óptima al paciente.Departamento de Cirugía, Oftalmología, Otorrinolaringología y FisioterapiaDoctorado en Ciencias de la Visió

Análisis morfogeométrico de la estructura hemiesférica del segmento anterior del ojo humano y su aplicación clínica

[SPA] Esta tesis doctoral se presenta bajo la modalidad de compendio de publicaciones.La superficie refractiva más importante del ojo humano es la córnea, que presenta una estructura de forma hemiesférica localizada en el segmento ocular anterior. Esta estructura, incluso en un escenario no patológico, no es perfecta, dado que presenta asimetrías que provocan deformaciones, desalineamientos y descentramientos entre ambos ojos del mismo individuo. Cuando además existen patologías corneales, como pueden ser las ectasias, esta asimetría, y por tanto sus efectos, se acentúan, provocando en el paciente un deterioro ciertamente importante de la capacidad visual, lo que da cuenta de la importancia de disponer de sistemas que permitan una caracterización corneal precisa que facilite la detección, diagnóstico y clasificación de las ectasias. En esta tesis doctoral se ha propuesto un sistema integrado capaz de detectar (fase preclínica) y diagnosticar (fase clínica), de manera eficiente y desde un punto de vista óptico-geométrico, la progresión de la ectasia corneal, permitiendo de esta forma incidir de manera directa en el proceso de toma de decisiones relativas a la calidad visual de los pacientes. Para ello, y partiendo de un modelo sólido personalizado en 3D generado con herramientas de Diseño Asistido por Ordenador, se han propuesto diversos parámetros morfogeométricos macroscópicos de tipo lineal, superficial, volumétrico y angular, con el objetivo de caracterizar la progresión de la ectasia corneal más importante, el denominado queratocono. La estructura microscópica también se ha estudiado, programando una aplicación que permite cuantificar el polimegatismo y el pleomorfismo de las células endoteliales corneales. Posteriormente, se han revisado los distintos sistemas univariantes y multivariantes de diagnóstico y clasificación del queratocono, y se ha comprobado que los parámetros morfogeométricos permiten tanto la detección como la clasificación del queratocono en base a su grado de severidad de acuerdo con las escalas RETICS, Amsler-Krumeich y Alió-Shabayek. Además, se han propuesto dos modelos predictivos (demográfico-óptico-geométricos) de clasificación del grado de la enfermedad en base a la escala RETICS, que han dado lugar al desarrollo de dos aplicaciones informáticas denominadas EMKLAS y KERATOSCORE, que a su vez dan cuenta de la dificultad inherente a la detección de esta enfermedad en la fase preclínica. Por último, se ha aplicado un modelo sólido personalizado obtenido mediante impresión 3D a la educación del paciente, comprobándose que la percepción visual y táctil del modelo permite a los pacientes entender mucho mejor su enfermedad y el tratamiento indicado para ella, mejorando la percepción de calidad del servicio prestado en las clínicas oftalmológicas.[ENG] This doctoral dissertation has been presented in the form of thesis by publication. The most important refractive surface of the human eye is the cornea, which has a hemispherical-shaped structure located in the anterior ocular segment. This structure, even in a non-pathological scenario, is not perfect, since it presents asymmetries that cause deformations, misalignments and decenterings between the two eyes of the same individual. When there are also corneal pathologies, such as ectasias, this asymmetry, and therefore its effects, are accentuated, causing in the patient a certainly significant deterioration of the visual capacity, something that shows the importance of having systems that allow precise corneal characterization to facilitate the detection, diagnosis and classification of ectasias. In this doctoral thesis, an integrated system capable of efficiently detecting (preclinical phase) and diagnosing (clinical phase), from an optical-geometric point of view, the progression of corneal ectasia, has been proposed, thus allowing a direct impact on the decision-making process concerning the visual quality of patients. To do so, and starting from a solid model customized in 3D generated with tools of Computer Assisted Design, several macroscopic morphogeometrical parameters of linear, superficial, volumetric and angular type have been proposed, with the aim of characterizing the progression of the most important corneal ectasia, the so-called keratoconus. The microscopic structure has also been studied, having programmed an application that allows to quantify the polymegatism and pleomorphism of the endothelial corneal cells. Subsequently, several univariate and multivariate diagnostic and classification systems for keratoconus have been revised, and it has been proven that morphogeometrical parameters allow both the detection and classification of keratoconus, basing on its degree of severity according to the RETICS, Amsler-Krumeich and Alió-Shabayek scales. In addition, two classification predictive models (demographical-optical-geometrical) of the disease degree based on the RETICS scale have been proposed, resulting in the development of two computer applications called EMKLAS and KERATOSCORE, which show the inherent difficulty of detecting this disease in its preclinical phase. Finally, a 3D printed personalized solid model has been applied to patient’s education, showing that the visual and tactile perception of the model allows patients to better understand their illness and the treatment indicated for it, improving the perception of quality of service provided in ophthalmological clinics.Las investigaciones que componen esta tesis doctoral se han llevado a cabo con el apoyo de la Red Temática para la Investigación Cooperativa en Salud (RETICS), referencia RD16/0008/0012, y han sido financiadas por el Instituto de Salud Calos III – Subdirección General de Redes y Centros de Investigación Cooperativa (Plan Nacional de I+D+I 2013-2016), el Fondo Europeo de Desarrollo Regional (FEDER), y el programa de Valorización de Resultados de la Universidad Politécnica de Cartagena (PROVALOR-UPCT).Esta tesis doctoral se presenta bajo la modalidad de compendio de publicaciones. Está formada por un total de doce documentos, todos ellos previamente publicados o aceptados para publicación. En concreto, 9 corresponden a artículos en revistas listadas en el ISI-JCR del Sciences Citation Index, mientras que los 3 restantes corresponden a capítulos de libro de la editorial Springer (Ranking Scholarly Publishers Indicators 4/200). Dichos documentos se enumeran a continuación de acuerdo con el orden cronológico en que han sido publicados durante el desarrollo de la investigación: 1. Cavas-Martínez F, Fernández-Pacheco DG, Cañavate FJF, Velázquez-Blázquez JS, Bolarín JM, Alió JL. Study of Morpho-Geometric Variables to Improve the Diagnosis in Keratoconus with Mild Visual Limitation. Symmetry. 2018;10(8):306. DOI: 10.3390/sym10080306. 2. Cavas-Martinez F, Fernandez-Pacheco DG, Canavate FJF, Velázquez-Blázquez JS, Bolarín J, Tiveron M, Alió J. Early keratoconus detection by patient-specific 3D modelling and geometric parameters analysis. Dyna. 2019. 94(2). DOI: 10.6036/8895. 3. Velázquez-Blázquez JS, Cavas-Martínez F, Alió del Barrio J, Fernandez-Pacheco DG, Cañavate FJF, Parras-Burgos D, Alió J. Detection of Subclinical Keratoconus Using Biometric Parameters. In: Rojas I., Valenzuela O., Rojas F., Ortuño F. (eds) Bioinformatics and Biomedical Engineering. IWBBIO 2019. Lecture Notes in Computer Science, vol 11466. Springer, Cham. DOI: 10.1007/978-3-030-17935-9_44. 4. Velázquez JS, Cavas F, Alió Del Barrio J, Fernández-Pacheco DG, Alió J. Assessment of the Association between In Vivo Corneal Morphogeometrical Changes and Keratoconus Eyes with Severe Visual Limitation. J Ophthalmol. 2019;2019:8731626-8731626. DOI: 10.1155/2019/8731626. 5. Velázquez-Blázquez JS, Cavas-Martínez F, Campuzano VA, Alió del Barrio J, Cañavate FJF, Alió J. Automatic image processing applied to corneal endothelium cell count and shape characterization. Dyna. 2020;95(2). DOI: 10.6036/9275. 6. Velázquez-Blázquez JS, Fernández-Pacheco DG, Alió del Barrio J, Alió JL, Cavas-Martínez F. Efficacy of Morpho-Geometrical Analysis of the Corneal Surfaces in Keratoconus Disease According to Moderate Visual Limitation. In: Cavas-Martínez F., Sanz-Adan F., Morer Camo P., Lostado Lorza R., Santamaría Peña J. (eds) Advances in Design Engineering. INGEGRAF 2019. Lecture Notes in Mechanical Engineering. Springer, Cham. 10.1007/978-3-030-41200-5_29. 7. Velázquez JS, Cavas F, Bolarín JM, Alió JL. 3D Printed Personalized Corneal Models as a Tool for Improving Patient’s Knowledge of an Asymmetric Disease. Symmetry. 2020;12(1):151. 10.3390/sym12010151. 8. Bolarín JM, Cavas F, Velázquez JS, Alió JL. A Machine-Learning Model Based on Morphogeometric Parameters for RETICS Disease Classification and GUI Development. Applied Sciences. 2020;10(5):1874. 10.3390/app10051874. 9. Velázquez JS, Cavas F, Bolarín JM, Alió JL. Comparison of Corneal Morphologic Parameters and High Order Aberrations in Keratoconus and Normal eyes. In: Rojas I., Valenzuela O., Rojas F., Ortuño F. (eds) Bioinformatics and Biomedical Engineering. IWBBIO 2020. Lecture Notes in Computer Science, vol 12108. Springer, Cham. DOI: 10.1007/978-3-030-45385-5_8. 10. Toprak I, Cavas F, Velázquez JS, Alió del Barrio JL, Alió JL. Subclinical keratoconus detection with three-dimensional (3-D) morphogeometric and volumetric analysis. Acta Ophthalmologica. (in press). 10.1111/aos.14433. 11. Velázquez JS, Cavas F, Piñero DP, Cañavate FJF, Alió del Barrio J, Alió JL. Morphogeometric analysis for characterization of keratoconus considering the spatial localization and projection of apex and minimum corneal thickness point. Journal of Advanced Research. (in press). DOI: 10.1016/j.jare.2020.03.012. 12. Velázquez-Blázquez JS, Bolarín JM, Cavas-Martínez F, Alió JL. EMKLAS: A New Automatic-Scoring System for Early and Mild Keratoconus Detection. Translational Vision Science & Technology. (in press). (2020).Escuela Internacional de Doctorado de la Universidad Politécnica de CartagenaUniversidad Politécnica de CartagenaPrograma de Doctorado en Tecnologías Industriale