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Tesi amb menció internacional, A la portada apareix el títol paral·lel en anglès: Chromatic performance of intraocular lenses with influence on the visual function, (English) Diffractive multifocal intraocular lens typically uses a hybrid refractive-diffractive design that consist of a high-power refractive base lens and a low-power diffractive profile engraved on one of its surfaces. These lenses are used to provide the pseudophakic eye with sharp vision, at near and far object distances, with a quality that depends on the design of the lens. This sort of lenses shows distinct wavelength dependence compared to purely refractive lenses. The measurements carried out with an eye model on optical bench revealed the asymmetry of energy efficiency distribution between the far and the near focus depending on the wavelength used and the diffraction order involved. In addition, the longitudinal chromatic aberration of the refractive and diffractive components, once combined, can reach different values in either focus depending on the diffraction order involved. The main purpose of this work is to prove whether the spectral behaviour of these lenses is transferred in some way to the visual perception and quality of the patient implanted with diffractive multifocal lenses. After some preliminary tests, it was found that the usual clinical measurement methods were insufficient to address the problem. Therefore, new methods and protocols were designed to assess visual function through high-contrast visual acuity (VA). Spatial and chromatic aspects of visual function were considered by establishing a wide range of viewing distances, light sources with different spectral content, and diverse groups of subjects. To detect the possible effects of this spectral behaviour on the visual function of patients implanted with diffractive intraocular lenses, a method for VA assessment was designed using specific optotypes illuminated, successively, with four LED light sources: one white (W) and three coloured (green (G), red (R), and blue (B)). Additional examinations were performed on monofocal pseudophakic and young phakic observers for the sake of, (Català) Les lents intraoculars multifocals difractives tenen un disseny híbrid refractiu-difractiu que consisteix en una lent base d'alta potència i un perfil difractiu de baixa potència incorporat en una de les superfícies. Aquestes lents es fan servir per proporcionar a l'ull implantat (pseudofàquic) una visió nítida de lluny i de prop, amb una qualitat que depèn del disseny de la lent. Aquests tipus de lents mostra una dependència singular amb la longitud d'ona en comparació amb les lents purament refractives. Les mesures realitzades al banc òptic amb un model d'ull van revelar les variacions de distribució d'eficiència energètica entre els focus de lluny i de prop segons la longitud d'ona utilitzada i l'ordre de difracció involucrat. A més, l'aberració cromàtica longitudinal dels components refractiu i difractiu pot assolir valors molt diferents a cada focus depenent de l'ordre de difracció que intervé. El propòsit central d'aquest treball és comprovar si el comportament espectral d"aquestes lents es trasllada d"alguna manera a la percepció visual del pacient implantat amb lents multifocals difractives. Després d'unes proves preliminars, es va observar que els mètodes de mesura clínics habituals eren insuficients per abordar el problema. Per això, es van dissenyar nous mètodes i protocols per avaluar la funció visual mitjançant l'agudesa visual (AV) d'alt contrast. Es van considerar aspectes espacials i cromàtics de la funció visual establint un ampli rang de distàncies de visió, fonts de llum amb contingut espectral diferent i diversos grups de subjectes. Per detectar els possibles efectes d'aquest comportament espectral a la funció visual dels pacients implantats amb lents difractives, es va dissenyar un mètode de mesura de l'AV utilitzant uns optotips específics il·luminats, successivament, amb quatre fonts de llum LED: una blanca (W) i tres de color (verd (G) vermell (R) i blau (B)). Per facilitar-ne la comparació, es van realitzar exàmens addicionals en gr, (Español) Las lentes intraoculares multifocales difractivas tienen un diseño híbrido refractivo-difractivo que consiste en una lente base de alta potencia y un perfil difractivo de baja potencia incorporado en una de sus superficies. Estas lentes se utilizan para proporcionarle al ojo implantado (pseudofáquico) una visión nítida de lejos y de cerca, con una calidad que depende del diseño de la lente. Este tipo de lentes muestra una dependencia singular con la longitud de onda en comparación con las lentes puramente refractivas. Las medidas realizadas en banco óptico con un modelo de ojo revelaron las variaciones de distribución de eficiencia energética entre los focos de lejos y de cerca según la longitud de onda utilizada y el orden de difracción involucrado. Además, la aberración cromática longitudinal de los componentes refractivo y difractivo puede alcanzar valores muy distintos en cada foco dependiendo del orden de difracción interviniente. El propósito central de este trabajo es comprobar si el comportamiento espectral de estas lentes se traslada de algún modo a la percepción visual del paciente implantado con lentes multifocales difractivas. Tras unas pruebas preliminares, se observó que los métodos de medida clínicos habituales eran insuficientes para abordar el problema. Por ello, se diseñaron nuevos métodos y protocolos para evaluar la función visual a través de la agudeza visual (AV) de alto contraste. Se consideraron aspectos espaciales y cromáticos de la función visual estableciendo un amplio rango de distancias de visión, fuentes de luz con diferente contenido espectral y diversos grupos de sujetos. Para detectar los posibles efectos de este comportamiento espectral en la función visual de los pacientes implantados con lentes difractivas, se diseñó un método de medida de la AV utilizando unos optotipos específicos iluminados, sucesivamente, con cuatro fuentes de luz LED: una blanca (W) y tres de color (verde (G) rojo (R) y azul (B)). Para facilitar la, Postprint (published version)

Background This study aims to detect alterations in the spatio-chromatic pseudophakic vision produced by multifocal diffractive intraocular lenses (IOLs) and provides a physical interpretation. Methods In vitro characterization of the imaging performance of two diffractive IOLs: AT LISA Tri (Zeiss) and FineVision (PhysIOL) in on-bench model eye illuminated with red (R, 625 nm), green (G, 530 nm) and blue (B, 455 nm) lights. We used the metrics: energy efficiency (EE), area under the modulation transfer function, longitudinal chromatic aberration (LCA), and halo intensity. Through-focus (TF) analysis and calculation of the expected defocus curve under white (W) daylight were included. In vivo visual acuity (VA) of 50 pseudophakics (60 eyes) was assessed under W, R, G, B lights at far and near. Two clinical experiments evaluated LCA and R, G, B TF-EE effects on pseudophakic vision and their relative importance. Results Clinical mean VA values under W light agreed with the predicted values at far and near for both IOLs. LCA measurements and R, G, B TF-EE curves were consistent with their lens design based on the 0th and 1st diffraction orders operative for far and near vision, respectively. LCA effects were compensated at near but noticed at far (-¿0.75 D under B light). We detected strong asymmetry in visual resolution depending on the object distance and the illuminating wavelength—red predominance at far, blue predominance at near—in consistency with the TF-EE measurements. Conclusions Diffractive multifocal IOL designs produce asymmetries in the spatio-chromatic vision of pseudophakics beyond the alterations strictly due to LCA. VA asymmetry for far/near object distance under R and B illumination is clinically detectable in subjects implanted with IOLs with 0th and 1st diffraction orders for far and near vision, respectively. Such VA asymmetry cannot be explained solely from the influence of defocus, as would be derived from a chromatic difference of power, but mai, Agencia Estatal de Investigación from Spanish Government (Grant No. PID2020-114582RB-I00/AEI/10. 13039/501100011033)., Peer Reviewed, Postprint (published version)

The defocus curve (DC) has become the gold standard method for assessing the visual performance at different distances, and hence, to evaluate the depth of focus that is provided by modern presbyopia-compensating intraocular lenses that are used in cataract surgery. A former study, carried out by other authors, reported that the DC method, based on placing the chart at far distance and using trial negative lenses, underestimated the visual acuity that was measured by varying the test distance (VD) in pseudophakic patients. We have revisited the issue with pseudophakic subjects and have extended the study to include young phakic observers with their natural accommodation preserved. Our results show that both the VD and DC methods are equivalent in precision and accuracy and can be used indistinctly. However, the DC method is more practical in the clinics because it does not require further control of the chart positioning and illuminance., This research funded by the Agencia Estatal de Investigación, Ministerio de Ciencia e Innovación of the Spanish government (PID2020-114582RB-I00/AEI/10.13039/501100011033)., Peer Reviewed, Postprint (published version)

Objetivo: Investigar la función visual en niños y adolescentes con trastorno por déficit de atención e hiperactividad (TDAH) y compararla con una muestra de pacientes sanos. Método: se realiza un examen optométrico completo a 22 niños de entre 7 y 17 años con trastorno por déficit de atención y 24 niños sanos apareados por sexo y edad. Resultados: las vergencias fusionales positivas y negativas son inferiores en el grupo con TDAH respecto al grupo control(positivas: ruptura19±7¿ vs 27±6¿ p<0.01 recuperación:15±6¿ vs 25±5¿ p<0.01;negativas: ruptura16±4¿ vs 19±4¿ p=0,008, recuperación13±5¿ vs 16±3¿ p=0.03).Conclusiones: los resultados de este estudio preliminar sugieren que los niños con TDAH presentan diferencias en algunos parámetros de la función visual respecto a la población sana, Postprint (published version)

Purpose: To assess the impact of the quasi-monochromatic illumination on visual acuity (VA) in phakic and monofocal pseudophakic eyes using different wavelengths. Methods: Sixty-one eyes classified in two groups (phakic and pseudophakic) participated in this study: 31 young phakic and 30 pseudophakic implanted with an acrylic monofocal intraocular lens. Distance VA was measured with custom optotype illuminated sequentially with three LED lights of nominal wavelengths (B) 455nm, (G) 530nm, (R) 625nm and white (W) LED light (CCT= 6500K). Near VA was additionally assessed in young phakic eyes under the same illuminations. Results: Best mean distance VA was obtained under red and white lights in young phakic eyes, whereas it was obtained under white and green lights in pseudophakic eyes. For both groups, the blue illumination led to the worst mean distance VA outcomes. No significant differences were found among mean near VA for R, G an B lights, but it was significantly better under W light than under B light. Conclusion: The measured distance VA values reveal the impact of the chromatic difference of refraction caused by the longitudinal chromatic aberration of the tested eyes. This aberration, is compensated by the accommodation capability of young phakics under red light. In the case of monofocal elderly pseudophakic eyes, a natural age-related decrease in the VA is observed. Additionally, the lack of accommodation, and a postoperative refraction outcome likely targeted for a green design wavelength, make the mean distance VA under green light match the one under white light. The mean near VA results in young phakic subjects revealed a balanced accommodation capability to every R, G, B illumination, but significantly higher under W light than under B light., This work was supported by the Spanish Ministerio de Economía y Competitividad and FEDER funds under project Ref. DPI2016-76019-R., Peer Reviewed, Postprint (published version)