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Myopia control with new designs of spectacle lenses is a flourishing area of research. The present work reviews the effectiveness of new designs (DIMSs, defocus-incorporated multiple segments; CARE, cylindrical annular refractive element; HALs/SALs, highly/slightly aspherical lenslets; DOT, diffusion optics technology) aiming at slowing myopia progression. A search through the PubMed database was conducted for articles published between 1 January 2003 and 28 February 2023. Publications were included if they documented baseline central refraction (SER) and/or axial length (AL) data, and the change in these parameters, in myopic children wearing new designs of spectacle lenses (treatment group) compared to myopic children using single-vision lenses, SVLs (control group). The selection process revealed nine suitable articles. Comparing the mean and standard error values of the treatment and control groups, the highest differences in the change in the SER and AL were -0.80 (1.23) D [95% CI: -1.053 to -0.547; p < 0.001] and 0.35 (0.05) mm [95% CI: 0.252 to 0.448; p < 0.001], respectively; the effect of treatment provided by a HAL design, compared to SVLs, led to a deceleration of 54.8% in the SER and 50.7% in the AL. However, the heterogeneity of the results prevents reaching strong conclusions about the effectiveness of these new designs., This research was supported by the Spanish Agencia Estatal de Investigación (project number PID2020-114582RB-I00)., Peer Reviewed, Objectius de Desenvolupament Sostenible::3 - Salut i Benestar, Postprint (author's final draft)

Purpose: Previous research has shown that accommodation deficits are common in individuals with Down syndrome (DS), but the origin and mechanisms behind these deficits are still unknown. The aim of this study was to investigate the characteristics of different ocular structures involved in accommodation, in particular the ciliary muscle (CM), in a population of individuals with DS to further understand this deficit and its mechanisms. Methods: Thirty-two volunteer participants of pre-presbyopic age with (n=16) and without DS (n=16) were recruited. Temporal and nasal images of the CM were acquired using anterior segment optical coherence tomography (AS-OCT) while participants fixated an eccentrically located target. Analysis of CM parameters was undertaken using validated semi-automated software. Axial length, anterior chamber depth, lens thickness and corneal curvature were obtained with the Topcon Aladdin Optical Biometer and Corneal Topographer. Non-cycloplegic refractive error and accommodative ability were obtained with an open-field autorefractor and dynamic retinoscopy, respectively. Independent t-tests were conducted to determine differences in CM and other anterior segment parameters between participants with and without DS. Results: No significant differences were found in the CM parameters studied between participants with and without DS (p>0.05). In contrast, significant differences were found in visual acuity (p<0.001), accommodative response (p<0.001) and corneal curvature (K1 p=0.003 and K2 p<0.001) between participants with and without DS. Conclusions: Despite having poorer accommodation, pre-presbyopic adults with DS do not have a different CM morphology to that found in typically developing adults. These findings suggest that the accommodative deficit found in this population is not due to a mechanical deficit of the CM., Fondation Jérôme Lejeune, Grant/Award Number: 1751 (session 2018A), Peer Reviewed, Postprint (published version)

Purpose: To validate the Spanish version of the Impact of Vision Impairment for Children (IVI_C), a vision-related quality of life (VRQoL) questionnaire, using Rasch Analysis. Methods: A translation and adaptation of the English IVI_C test was performed according to the standards published in PedsQL. The IVI_C Spanish version of the test was administered by email to 101 Sant Joan de Déu Hospital patients who were invited to respond twice, with a minimum interval of two months. The age of the patients ranged from 8 to 18 years. Statistical software SPSS 19.0 (Armonk, NY: IBM Corp.) was used to perform the statistical analyses to test the internal consistency of the scale, the test-retest, the intraclass correlation consistency and the Rasch Analysis. Results: Results ranging from good to excellent were obtained for the internal consistency of the scale, the testretest and the intraclass correlation, depending on the scale used, and Rasch Analysis validated to simplify the original test. The statistical analysis of the 24 original items was carried out, and the 6 items that provided almost no contribution to the overall score were removed. Thus, 18 out of the 24 items in the original test were selected. Conclusion: The Spanish version of the IVI_C QoL test with 18 items is a valid tool to assess the quality of life of patients with visual loss who do not have additional disabilities., Peer Reviewed, Postprint (published version)

Strabismus is not a condition in itself but the consequence of an underlying problem. Eye misalignment can be caused by disease, injury, and/or abnormalities in any of the structures and processes involved in visual perception and oculomotor control, from the extraocular muscles and their innervations to the oculomotor and visual processing areas in the brain. A small percentage of all strabismus cases are the consequence of well-described genetic syndromes, acquired insult, or disease affecting the extraocular muscles (EOMs) or their innervations. We will refer to them as strabismus of peripheral origin since their etiology lies in the peripheral nervous system. However, in most strabismus cases, that is comitant, non-restrictive, non-paralytic strabismus, the EOMs and their innervations function properly. These cases are not related to specific syndromes and their precise causes remain poorly understood. They are generally believed to be caused by deficits in the central neural pathways involved in visual perception and oculomotor control. Therefore, we will refer to them as central strabismus. The goal of this narrative review is to discuss the possible causes behind this particular type of eye misalignment and to raise awareness among eyecare professionals about the important role the central nervous system plays in strabismus etiology, and the subsequent implications regarding its treatment. A non-systematic search was conducted using PubMed, Medline, Cochrane, and Google Scholar databases with the keywords “origins,” “causes,” and “etiology” combined with “strabismus.” A snowball approach was also used to find relevant references. In the following article, we will first describe EOM integrity in central strabismus; next, we will address numerous reasons that support the idea of central nervous system (CNS) involvement in the origin of the deviation, followed by listing several possible central causes of the ocular misalignment. Finally, we will discuss the imp, Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature., Peer Reviewed, Postprint (published version)

Eye movement control is impaired in some neurological conditions, but the impact of COVID-19 on eye movements remains unknown. This study aims to investigate differences in oculomotor function and pupil response in individuals who suffer post-COVID-19 condition (PCC) with cognitive deficits. Saccades, smooth pursuit, fixation, vergence and pupillary response were recorded using an eye tracker. Eye movements and pupil response parameters were computed. Data from 16 controls, 38 COVID mild (home recovery) and 19 COVID severe (hospital admission) participants were analyzed. Saccadic latencies were shorter in controls (183¿±¿54 ms) than in COVID mild (236¿±¿83 ms) and COVID severe (227¿±¿42 ms) participants (p¿=¿0.017). Fixation stability was poorer in COVID mild participants (Bivariate Contour Ellipse Area of 0.80¿±¿1.61°2 vs 0.36¿±¿0.65 °2 for controls, p¿=¿0.019), while percentage of pupil area reduction/enlargement was reduced in COVID severe participants (39.7¿±¿12.7%/31.6¿±¿12.7% compared to 51.7¿±¿22.0%/49.1¿±¿20.7% in controls, p¿<¿0.015). The characteristics of oculomotor alterations found in PCC may be useful to understand different pathophysiologic mechanisms., Project PID2020-112527RB-I00 funded by MCIN/AEI/10.13039/501100011033; La Marató de TV3 Foundation (202111-30-31-32)., Peer Reviewed, Postprint (published version)

Two tests to measure fusional vergence amplitudes objectively were developed and validated against the two conventional clinical tests. Forty-nine adults participated in the study. Participants’ negative (BI, base in) and positive (BO, base out) fusional vergence amplitudes at near were measured objectively in an haploscopic set-up by recording eye movements with an EyeLink 1000 Plus (SR Research). Stimulus disparity changed in steps or smoothly mimicking a prim bar and a Risley prism, respectively. Break and recovery points were determined offline using a custom Matlab algorithm for the analysis of eye movements. Fusional vergence amplitudes were also measured with two clinical tests using a Risley prism and a prism bar. A better agreement between tests was found for the measurement of BI than for BO fusional vergence amplitudes. The means ± SD of the differences between the BI break and recovery points measured with the two objective tests were -1.74 ± 3.35 PD and -1.97 ± 2.60 PD, respectively, which were comparable to those obtained for the subjective tests. For the BO break and recovery points, although the means of the differences between the two objective tests were small, high variability between subjects was found (0.31 ± 6.44 PD and -2.84 ± 7.01 PD, respectively). This study showed the feasibility to measure fusional vergence amplitudes objectively and overcome limitations of the conventional subjective tests. However, these tests cannot be used interchangeably due to their poor agreement., This study is part of the project PID2020-112527RB-I00, funded by MCIN/AEI/10.13039/501100011033. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript., Peer Reviewed, Postprint (published version)

PURPOSE: To determine the institutions, journals of choice and topics of investigation of the most prolific and highly cited Spanish optometrist researchers. METHODS: As a primary search strategy, the Scopus database (Elsevier) was queried with the terms (optometr* OR "contact lens*" OR refracti* OR *ocular) and the affiliation country filter “Spain”. The list of authors returned by the primary search was used in a secondary manual search based on co-authors and institutions. Authors were included in the analysis if they had an h-index > 10, were of Spanish nationality, were affiliated to Spanish institutions, and possessed an optometry degree. Authors were ranked by h-index, number of publications and number of citations. Topics of research interest and target journals were determined by analyzing the 10 most highly cited papers of each author. RESULTS: A total of 32 authors with an h-index > 10 were identified, of whom 14 (43.7%) were female. Only one author had an h-index > 40, and 7 (21.9%) authors had an h-index over 20. The Journal of Cataract and Refractive Surgery was the first journal of choice (19.1% of highest cited papers), followed by Optometry and Vision Science (10.3%). The Universidad Complutense de Madrid hosted the largest percentage of authors (18.7%), followed by the Universitat de València (15.6%). Main topics of research interest were topography (6.5% of papers), cornea (6.2%) and contact lens (5.0%). CONCLUSION: Optometry in Spain is a fertile field of research, with an increasing number of highly cited authors publishing in high impact journals., Peer Reviewed, Postprint (author's final draft)

Clinical relevance Measuring axial length is key in the field of myopia development and control. Hence, the precision and agreement of commercially available biometers is of vital interest to understand their variability and interchangeability in the paediatric population. Background Different biometers are available to measure axial length and monitor myopia progression in clinical practice. The purpose of this study was to assess the precision (repeatability and reproducibility) and agreement of the MYAH and AL-Scan biometers in a paediatric population. Methods Three consecutive measurements were performed using MYAH and AL-Scan biometers in each subject by the same operator to test for repeatability. To test for reproducibility, two measurements were performed for each subject by two different observers with a 5-min interval between measurements. To test the agreement, each subject was measured once with each instrument. Results A total of 187 subjects, with a mean age of 8.5¿±¿0.3¿years and mean spherical equivalent refractive error of¿+0.22¿±¿0.77 D participated in the study. For the repeatability study, the within-subject standard deviation was 0.01¿mm, and the repeatability limit was 0.04¿mm for both instruments, with no statistically significant differences among repeated measures (p¿=¿0.162 for MYAH and p¿=¿0.774 for AL-Scan). For the reproducibility study, the within-subject standard deviation was 0.01¿mm and the repeatability limit was 0.04¿mm. There were statistically significant differences for the repeated measures for the AL-Scan (p¿=¿0.002) but not for the MYAH (p¿=¿0.643). Regarding the agreement between both instruments, the 95% limit of agreement ranged from -0.04 to 0.05¿mm, and the differences were statistically significant (p¿=¿0.021). Conclusions The repeatability, reproducibility, and agreement of the MYAH and AL-Scan biometers seem optimal for following children with myopia., Mikel Aldaba is a Serra Húnter Fellow. Valldeflors Vinuela-Navarro is funded by “Ministerio de Universidades” and “European Union – NextGenerationEU”., Peer Reviewed, Postprint (author's final draft)

Purpose To compare the performance in the Developmental Eye Movement test (DEM) and the Test of Visual Perceptual Skills (TVPS) between three groups: individuals with strabismus and amblyopia, patients with binocular and accommodative dysfunctions, and subjects with normal binocular and accommodative function. Methods A multicentric, retrospective study including 110 children aged 6–14 years old was conducted to investigate the potential impact of strabismus, amblyopia, and different binocular conditions in DEM results (adjusted time in vertical and horizontal parts) and TVPS (percentiles in the seven sub-skills). Results No significant differences were found in the different subtests of the vertical and horizontal DEM and all the sub-skills in the TVPS between the three groups of the study. We found high variability of performance in the DEM test between participants with strabismus and amblyopia compared with binocular and accommodative problems. Conclusion DEM and TVPS scores have not been found to be influenced by the presence of strabismus with or without amblyopia, nor by binocular and accommodative dysfunctions. A slightly correlation tendency with horizontal DEM and degree of exotropia deviation was observed., Peer Reviewed, Postprint (author's final draft)

Peer Reviewed, Postprint (published version)

Background: Receiving a diagnosis of a child with untreatable visual impairment (VI) may have a negative impact on parents and caregivers, and affect their quality of life (QoL). Aims: To use a qualitative research approach to determine the impact that caregiving a child with a VI has on the QoL of caregivers in Catalonia (Spain). Methods: An observational study was designed in which nine parents of children with VI (6 mothers) were recruited following an intentional sampling scheme. In-depth interviews were conducted, and a thematic analysis was performed to identify main themes and subthemes. The QoL domains defined in the questionnaire WHOQoL-BREF guided data interpretation. Results: An overarching theme was defined (the weight on one’s shoulders), as well as two main themes (obstacles race and emotional impact) and seven subthemes. QoL was negatively affected by a general lack of knowledge and understanding regarding VI in children and its implications for children and caregivers, whereas social support, gaining knowledge, or cognitive reappraisal had a positive effect. Conclusions: Caregiving for children with VI affects all QoL domains, resulting in persistent psychological distress. Both administrations and health care providers are encouraged to develop strategies to assist caregivers in their demanding roles., Peer Reviewed, Objectius de Desenvolupament Sostenible::5 - Igualtat de Gènere, Objectius de Desenvolupament Sostenible::3 - Salut i Benestar, Objectius de Desenvolupament Sostenible::10 - Reducció de les Desigualtats, Postprint (author's final draft)

Purpose: The inter-session repeatability (ISR), inter-examiner reproducibility (IER) and within-subject variability (WSV) of the Cobra HD fundus camera meibographer were examined in participants with and without dry eye symptoms.Methods: Symptoms were determined based on Ocular Surface Disease Index scores (=13 being considered symptomatic), and subgroups were compared using the Mann– Whitney U- test. Images of meibomian glands (MGs) from the upper and lower right eyelids were captured by two examiners on the same day (S1) to determine IER. One examiner repeated the measurements on a second day (S2) to obtain the ISR. ISR, IER and WSV were calculated using Friedman, correlation tests and Bland and Altman analyses with mean differences (md) and 95% confidence intervals (CIs), within-subject standard deviations (Sw) and intra-class correlation coefficients (ICC).Results: The ISR experiment included 72 participants (mean age: 23 ± 5 years, range: 19–43, 36 symptomatic). Mean MG loss of the upper (S1: 13.5 ± 9.5%, S2: 12.8 ± 8.5%) and lower eyelids (S1: 7.5 ± 6.9%, S2: 7.3 ± 6.3%) was not significantly different between sessions for all participants, symptomatic and asymptomatic subgroups for both eyelids. The ISR Sw for the upper and lower eyelids was 1.3% and 1.0%; md was 0.7 ± 3.5% (CI:-6.25% to 7.62%) and 0.1 ± 2.1% (CI: -3.94% to 4.17%), respectively. The IER experiment included 74 participants (mean age: 23 ± 5 years, range: 19–43, 37 symptomatic). Mean MG loss of the upper (Examiner 1: 12.7 ± 8.2%, Examiner 2: 13.1 ± 8.0%) and lower eyelids (Examiner 1: 7.0 ± 6.2%, Examiner 2: 7.4 ± 6.2%) was not significantly different between examiners for all participants, symptomatic and asymptomatic subgroups for both eyelids. The IER ICC values were >0.86 for all conditions, Sw was 1.3% and 1.2%, with a md of -0.4 ± 3.2% (CI: -6.65% to 5.90%) and -0.4 ± 2.9% (CI: -6.15% to 5.31%), respectively. The WSV Sw values were <1.4%, and ICC values were >0.89 for both eyelids, examin, Peer Reviewed, Postprint (published version)

Social inclusion involves the dynamics that link the development of capacities with access to opportunities, well-being, relationship networks, and the exercise of citizenship. This study sought to understand the meanings on social inclusion of people with visual impairment from four cities in Colombia, as well as the family dynamics that favor or hinder inclusion processes. A qualitative exploratory study was conducted, by applying 26 semi-structured interviews via telephone. The interviews were transcribed and the themes extracted by the authors. The three emerging categories were the following: (1) My disability does not measure me: it is a way of living and being in the world; (2) deconstructing imaginaries: a wager on inclusion; and (3) from the family, the most important is letting be. Our results indicate that social inclusion is mediated by the meanings they assign to their own condition of visual impairment, by the existing social imaginaries on the theme, and by the family dynamics or the nearby environment. The work recognized the following as facilitators: acceptance of the disability by those who have the condition and by their close environment; recognition of the disability as part of human diversity; the family as actor that recognizes, respects individuality, and promotes their development; and the individual skills to cope with the situation and find a support network. Barriers were the negative imaginaries and the biomedical view that persist in society, which interact with the daily lives of the people, thus generating situations of exclusion., The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The Project was cofunded by Colombia’s National Institute for the Blind and Universidad Santo Tomás-Bucaramanga. Research project: Configuration of daily practices undertaken by people with visual impairment, their families, and/or the nearby environment that permit identifying barriers and facilitators for social inclusion, Peer Reviewed, Objectius de Desenvolupament Sostenible::10 - Reducció de les Desigualtats, Objectius de Desenvolupament Sostenible::3 - Salut i Benestar, Postprint (author's final draft)

PURPOSE: To validate Spanish Low Vision Qualify of Life (SLVQOL) questionnaire, a quality of life instrument specifically designed for patients with visual impairment, and evaluate its psychometric properties. METHODS: The study included 170 visually impaired patients and 195 healthy subjects. Participants were administered the SLVQOL, the NEI VFQ-25, and the EQ 5D-5L questionnaires. Reliability, test–retest reproducibility, feasibility, and construct validity of the SLVQOL were assessed. The Generalized Partial Credit Model was used to fit the data and the performance of each item was characterized using category response curves and item information. RESULTS: The reliability of the SLVQOL was 0.981 (95% CI: 0.978—0.985). Test–retest reproducibility was good (¿=0.864, P < .001). A cut-off point of 105 or 106 was optimal to detect visual impairment, with a sensitivity of 95.4% and a specificity of 91.8%. Construct validity was shown by the corresponding convergence or divergence correlations between the score of the SLVQOL and its dimensions and the overall and partial scores of the NEI VFQ-25 and the EQ 5D-5L. Item response theory analysis showed discrimination and information parameters ranging from 0.539 to 3.063 and from -1.894 to 1.074, respectively. CONCLUSION: The SLVQOL was able to quantitatively assess and identify differences in the quality of life among patients with visual impairment and normal subjects. The psychometric properties evaluated suggest that this tool has excellent validity, internal consistency, and reproducibility, but may benefit from a reduction of the number of items., Peer Reviewed, Postprint (author's final draft)

Low vision is a condition of visual impairment, generated by an underlying pathology that affects visual functioning and the development of daily activities. In the field of visual impairment, the developments in the analysis of access to rehabilitation services are scarce and incipient. The study approaches the understanding of the experiences of people with low vision in Medellín, Colombia, in their search for visual rehabilitation services. Ethnographic collective case study was conducted. Intersectionality was adopted to explore people’s experiences with low vision management health services. Five women and four men with low vision who attended the healthcare center participated in the study. Twenty-nine interviews and 16 participant observation exercises were carried out. Three categories emerged in the study: (1) I had never heard of low vision services; (2) Interaction with the health system: A path of struggles; and (3) Barriers that are exacerbated by the intersection of multiple identities and systems of oppression. The Colombian health system acts as an axis of structural oppression that interacts with the economic condition, educational level, and geographical location to generate greater difficulties for the identification of low vision management options, which also interact with the multiple and dynamic identities of each subject., Peer Reviewed, Objectius de Desenvolupament Sostenible::3 - Salut i Benestar, Objectius de Desenvolupament Sostenible::10 - Reducció de les Desigualtats, 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)

Electronic sports (e-sports) have recently emerged to become a rapidly growing form of videogame competition, requiring gamers to spend many hours in front of a visual display. The nature of this new modality raises important considerations for ocular health, and visual and perceptual functioning, compared to traditional sports. In general, sports performance has been associated with open spaces, gross motor movement, and balance, while electronic sports require visual and attentional stamina at near distances with fine motor control. From an optometric viewpoint, visual perception is specific to both the sports modality and the environment where sports take place. In this topical review, we consider e-sport optometric factors such as screen time and digital eyestrain, visual skill demands, and perceptual cognitive skills such as visual attention. We compare training considerations for traditional sports and training in gaming platforms, with recommendations for future research in this growing modality. The goal of this review is to raise awareness of the various elements to consider when providing vision care to e-sport participants., Peer Reviewed, Postprint (author's final draft)

The clinical importance of peripheral refraction as a function of accommodation has become increasingly evident in the last years with special attention given to myopia control. Low order ocular aberrations were measured with a Hartmann–Shack aberrometer in a sample of 28 young emmetropic subjects. A stationary Maltese cross was presented at 2.5 D and 5.0 D of accommodative demand and at 0¿ , 10¿ and 20¿ of eccentricity in the horizontal visual field under two different illumination conditions (white and red light). Wavefront data for a 3 mm pupil diameter were analyzed in terms of the vector components of refraction (M, J0 and J45) and the relative peripheral refractive error (RPRE) was calculated. M was myopic at both accommodative demands and showed a statistically significant myopic increase with red illumination. No significant change in J0 and J45 was found with accommodation nor between illumination conditions. However, J0 increased significantly with eccentricity, exhibiting a nasal-temporal asymmetry. The RPRE was myopic at both accommodation demands and showed a statistically significant hyperopic shift at 20¿ in the nasal retina. The use of red light introduced statistically and clinically significant changes in M, explained by the variation of the ocular focal length under a higher wavelength illumination, increasing the experimental accommodative demand. These findings may be of relevance for research exploring peripheral refraction under accommodation, as the choice of target illumination is not trivial., This research was funded by the Agencia Estatal de Investigación, Ministerio de Ciencia e Innovación of the Spanish government (PID2020-114582RB-I00/AEI/10.13039/501100011033). This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 956720, Peer Reviewed, Postprint (published version)

Contact lens (CL) wearers often suffer from ocular discomfort, which leads to cessation of CL wear. About 30% to 50% of CL wearers complain of dry eye (DE) symptoms. Meibomian gland dysfunction (MGD) is considered the most common cause of evaporative DE. Numerous studies have investigated whether CL wear might affect the meibomian glands. This manuscript reviews studies examining the relationship between CL use and MGD. A PubMed database search was conducted for studies published between 1980-2021 with one or a combination of search terms related to “meibomian gland”, “meibomian gland dysfunction”, “contact lens”, and/or “dry eye”. Of the 115 papers reviewed, 22 articles were identified that examined the association between CL and MGD. Fifteen showed that CL wear affects the morphology and function of meibomian glands (MGs), while seven reported no significant impact of CL wear on MGs. This review provides an overview of these studies, emphasizing the diagnostic tests of MGD and conclusions. The review highlights the need for longitudinal prospective large cohort studies with control non- CL wearers to clarify the ambiguous relationship between MGD and CL wear, with special attention to varying CL material and wear times in order to identify the long-term impact of CLs on MG., Peer Reviewed, Postprint (author's final draft)

There is currently no treatment for early/intermediate Age-related Macular Degeneration (AMD) but Eye Care Professionals (ECPs) are recommended to advise patients about modifiable lifestyle factors, including dietary changes, that can slow disease progression. The aim of this review was to understand advice currently given to patients with AMD by ECPs and to evaluate evidence regarding patient compliance. A systematic review was conducted of literature published in electronic databases: CINAHL, MEDLINE, PsycINFO, PyscARTICLES, EMBASE, AMED. Methods followed PRISMA guidelines (PROSPERO registration number: CRD42020223724). Twenty-four reports were eligible for inclusion, 12 focused on ECP experience, 7 on patient experience, and 6 on impact of advice (one paper reported on the ECP and patient experience). Studies reported that a substantial proportion of patients did not recall receiving lifestyle modification advice from their ECP (57.95%, range 2–95% across patient based studies). Practitioners were most likely to provide advice about nutritional supplements (80%, range 67–93% across ECP studies), and least likely about smoking (44%, range 28–71% across ECP studies), however supplements advised did not always comply with evidence-based guidelines. The main reason for patients not following lifestyle advice was lack of provision by the ECP (54.5%, range 21–94% across studies on the impact of advice). The review highlighted a need for more studies to understand patient preferences for receiving advice and research on ECP perceived barriers to advice provision., S.D. is funded by The Macular Society, Peer Reviewed, Postprint (author's final draft)

Propósito: El propósito de esta investigación fue determinar las prácticas de los usuarios de lentes de contacto en referencia al cuidado y reemplazo del estuche portalentes. Métodos: Se desarrolló una encuesta en línea y se distribuyó siguiendo una estrategia de muestreo en forma de bola de nieve. Resultados: Se recopilaron y analizaron 247 respuestas. La mayoría de los usuarios seguían un reemplazo mensual de sus lentes (64,8%) y el 86,6% utilizaba un estuche portalentes. De estos, un 25,0% indicaron que nunca limpiaban el estuche y un 15,0% que nunca lo reemplazaban. Un 30,0% respondieron que su profesional de la visión nunca les había informado sobre la necesidad de limpiar y reemplazar el estuche. Conclusión: Existe un elevado incumplimiento y desconocimiento en el uso y cuidado del estuche portalentes, lo que subraya la necesidad de fomentar y mejorar las estrategias de comunicación entre los profesionales de la visión y sus pacientes., Peer Reviewed, Postprint (published version)

Peer Reviewed, Postprint (published version)

Purpose: To determine the efficacy, predictability and safety of long-term orthokeratology in children and adults. Methods: Case histories of 300 orthokeratology patients (596 eyes; 34.3% children; 65.7% adults) were reviewed to collect information on demographics, corneal and refractive parameters, visual acuity, residual refraction and adverse effects. Predictability was defined as the percentage of eyes with absolute values of spherical equivalent refraction = 0.5 D of emmetropia, and efficacy as the ratio of post-orthokeratology uncorrected and pre-orthokeratology corrected distance visual acuity. Results: Median duration of treatment was 37 and 28.5 months in children and adults, respectively (p = 0.022). During the first year, 17.2% of children and 33% of adults ceased lens wear (p < 0.001). For children and adults with a successful ortho-k treatment of at least one year of duration, 88.7% and 95.9% of eyes had a predictable refractive outcome, and efficacy was 0.98 and 1.01, respectively. A larger percentage of children (65.7%) were free of complications than of adults (55.4%) (p = 0.015). One event of microbial keratitis occurred in adults (6.8 cases per 10,000 patient-years) and none in children. Corneal staining was the most frequent complication, with a higher incidence in adults (p = 0.007) and in higher myopia (p < 0.001), higher anterior corneal eccentricity (p = 0.019) and smaller anterior horizontal radius (p = 0.027). Conclusion: Orthokeratology is a safe and predictable long-term procedure in children and adults, with a low incidence of serious adverse effects. Corneal staining episodes are relatively frequent throughout the course of the treatment, thus highlighting the relevance of education of experienced users., Peer Reviewed, Postprint (author's final draft)

La calidad acústica del ambiente en que se realiza el aprendizaje puede ser determinante a la hora de obtener mejores resultados. Así pretende demostrarlo un estudio realizado en la Facultad de Óptica y Optometría de Terrassa (FOOT) con una muestra de 42 estudiantes de entre 19 y 25 años. En esta investigación se han cruzado tanto las condiciones acústicas de diferentes aulas, como los hábitos que esta franja de edad tiene y cómo afectan a su audición., Peer Reviewed, Postprint (author's final draft)

Salud pública: fundamentos conceptuales, ofrece una revisión introductoria a los conceptos de salud, salud pública y sus dimensiones social y política, desde el derecho a la salud y la reflexión acerca de las desigualdades en salud general y en el caso específico de la salud visual., Peer Reviewed, Postprint (published version)

Purpose: The purpose of this study was to evaluate changes in visual acuity, corneal curvature, elevation, pachymetry, and objective quality of vision, of experienced orthokeratology patients using their contact lenses during a simulated 30-minute afternoon nap. Method: Twelve patients aged 30.8±8.3 years were recruited for the study, with a history of overnight orthokeratology of 27.4±23.0 months. Patients were instructed to close their eyes for 30 minutes while wearing their contact lenses or without lenses. Anterior corneal curvature, elevation and corneal pachymetry were assessed with the Pentacam Scheimpflug System at 17 predefined corneal locations and the HD Analyzer was used to measure objective quality of vision. Measurements were conducted before eye closure (baseline), immediately after eye opening/lens removal (M1) and 30 minutes later (M2). Results: No statistically significant differences were found in anterior corneal curvature and elevation between baseline values and M1 or M2, with and without contact lenses. Corneal swelling at M1 was greater without contact lenses (change in central corneal thickness of 2.3% ± 3.1%, p=0.001) than with contact lenses (1.7% ± 1.3%, p<0.001). Recovery at M2 was slower when lenses were worn. A statistically significant improvement in objective quality of vision and visual acuity was found only when patients napped with their lenses. Conclusions: Even if no significant changes were found in corneal curvature and elevation, patients of overnight orthokeratology may benefit from using their contact lenses during their afternoon nap in terms of objective quality of vision and visual acuity., Peer Reviewed, Postprint (author's final draft)

Peer Reviewed, Postprint (published version)

Purpose Ocular manifestations and ocular transmission of SARS-CoV-2 in contact lens (CL) wearers may be fostered by non-compliance with care and maintenance instructions which, in turn, may be aggravated by inadequate patient-practitioner communication. The purpose of this research was to determine CL use, compliance and patient-practitioner communication during a 3-month long COVID-19 lockdown in Spain. Methods An online survey (developed using Google Forms) retrospectively evaluated CL compliance during the 3-month lockdown (responses captured between 15th July and 10th August, 2020), with particular emphasis on patient-practitioner communication, handwashing practices and CL case hygiene and replacement. Results A total of 247 responses were collected and analysed. Most participants used monthly replacement soft lenses (64.8 %) and multipurpose solutions (75.7 %), with 86.6 % of them owning a storage case for their lenses. During lockdown, a significant percentage of participants ceased lens wear (28.4 %) or reduced wearing time (49.2 %). Regarding patient-practitioner communication, 54.3 % of respondents received specific instructions, mostly about handwashing (93.3 %) and storage case hygiene (48.5 %). The most frequent non-compliant practices were inadequate handwashing (36.4 %), and overextending monthly or two-weekly replacement lenses (35.2 %). Many respondents never cleaned (23.0 %) nor replaced (16.3 %) their storage case, and 27.8 % of them reported not having been informed about case hygiene by their practitioners. Conclusion Contact lens compliance, particularly in terms of handwashing and storage case hygiene, was poor during a prolonged COVID-19 lockdown, thus stressing the need to foster patient-practitioner communication strategies to curtail the possibility of ocular transmission and the risk of virus tropism., Peer Reviewed, Postprint (author's final draft)

Peer Reviewed, Postprint (published version)

Peer Reviewed, Postprint (published version)

Páramo ecosystems harbor important biodiversity and provide essential environmental services such as water regulation and carbon sequestration. Unfortunately, the scarcity of information on their land uses makes it difficult to generate sustainable strategies for their conservation. The purpose of this study is to develop a methodology to easily monitor and document the conservation status, degradation rates, and land use changes in the páramo. We analyzed the performance of two nonparametric models (the CART decision tree, CDT, and multivariate adaptive regression curves, MARS) in the páramos of the Chambo sub-basin (Ecuador). We used three types of attributes: digital elevation model (DEM), land use cover (Sentinel 2), and organic carbon content (Global Soil Organic Carbon Map data, GSOC) and a categorical variable, land use. We obtained a set of selected variables which perform well with both models, and which let us monitor the land uses of the páramos. Comparing our results with the last report of the Ecuadorian Ministry of Environment (2012), we found that 9% of the páramo has been lost in the last 8 years., 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)

Peer Reviewed, Postprint (author's final draft)

Purpose: The purpose of this prospective, randomized, double masked, study was to compare the visual performance of patients after bilateral implantation of six different IOLs. Methods: The following IOLs were used in the study: SV25T0 (n=19), ATLISA 809M (n=18), ATLISA Tri 839MP (n=19), ZKB00 (n=20), ZLB00 (n=20) and Symfony ZXR00 (n=20). Visual performance was assessed by the monocular distance corrected visual acuity at 4m (CDVA), distance corrected intermediate visual acuity (DCIVA) at 60cm and distance corrected near visual acuity (DCNVA) at 40cm. Binocular defocus curves were obtained for a range of defocus from +1.50D to -4.50D, in 0.50D steps. Quality of life was assessed with the VF-14 questionnaire. Results: DCVA was better with the Symfony ZXR00 than with the SV25T0 (p=0.032), ATLISA Tri 839MP (p=0.032) and ATLISA 809M (p=0.018). The Symfony ZXR00 offered the best DCIVA, followed by the ZKB00. The best and worst DCNVA results corresponded to the ZLB00, and the SV25T0 and Symfony ZXR00, respectively. Defocus curves at distance were good in all groups, although the Symfony had a wider range of clear vision (-1.50D to +0.50D), with no decay. For intermediate vision, only the Symfony obtained sharp visual acuity. The ATLISA 809M, ATLISA Tri 839MP and ZLB00 were superior at near. Conclusions: The extended depth of focus of the Symfony ZXR00 offers a superior range of clear vision at far and intermediate distances than other multifocal designs, with worse results at near. Visual outcomes reflect the particular optical, geometrical and power distribution characteristics of each IOL., Peer Reviewed, Postprint (author's final draft)

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)

Peer Reviewed, Preprint

Purpose: To explore the laymen knowledge of low vision and blindness concepts, and to assess the readability of some on-topic information available online. Methods: A cross-sectional study was performed in March 2019. Knowledge was evaluated by means of an ad hoc questionnaire-survey with two dichotomous questions about concepts related to low vision and blindness, followed with a list of 10 true-or-false statements. Readability of two on-topic online texts of different complexity was evaluated asking participants to rate the difficulty they experienced on a Likert scale and, objectively, by means of the freeware INFLESZ Readability Scale for Spanish language. Data analysis included descriptive statistics, t-tests, and ANOVA test (statistical significance: p<0.05). Results: Fifty-two percent of 103 participants declared never having heard of low vision. Ninety-four percent participants were aware about the word blindness, although most of them misinterpreted it. Neither academic level nor age influenced knowledge (p=0.425 and p=0.382 for low vision; p=0.967 and p=0.060 for blindness). Higher academic level was related to better readability scores of the complex online text (p<0.05). Conclusion: Overall, the general public has a limited awareness of low vision and a large misconception of blindness. Therefore, visual health education actions should aim at fostering knowledge and literacy on the issue. This strategy may encourage individuals to seek the advice of eye care providers in order to prevent and treat visual impairment, with relevant consequences in time, both in terms of quality of life and costs., Peer Reviewed, Postprint (author's final draft)

Background: The objective of this study is to assess the prevalence of visual impairment and visual care practices and its association with socioeconomic conditions in the infant population in Catalonia. Methods: The Catalan Institute of Statistics provided a random sample of 0 to 14-year-old non-institutionalized children whose parents were interviewed in a continuous health survey from 2011 to 2015 in Catalonia. A multistage stratified and random sampling procedure considering age, sex, county and town was followed. All results have been weighted according to the sample design and are presented as the proportion of the condition with its 95% confidence limits. Chi-square tests were performed to evaluate the association between categorical variables. To study the association of visual care with independent variables, a multiple logistic regression model was used. Results: In 0 to 14-year-old children, a 12.9% (95% confidence interval [CI] [11.8–13.9]) prevalence of correctable visual impairment was observed. The prevalence of non-correctable visual impairment was 0.9% (95% CI [0.6–1.2]). Noncorrectable visual impairment was more prevalent in families with lower education levels, manual professions or unemployed. Of children without visual impairment, 13,5% (95% CI:12.3–14.6) visited a visual care professional in the last 12 months while this proportion was 67.4% (95% CI [63.3–71.5]) among those with correctable visual impairment. When parents have a university degree or non-manual professions, a higher level of visual care was observed. In children with correctable visual impairment, visual reviews were more frequent when parents are employed in a non-manual profession. Conclusions: For the first time, indicators related to visual impairment in children in Catalonia have been recorded. There is an association between lower socioeconomic status and having non-correctable visual impairment, and conversely, having correctable visual impairment was significantly associ, Peer Reviewed, Postprint (author's final draft)

Purpose: It could be argued that current studies investigating smooth pursuit development in children do not provide an optimal measure of smooth pursuit characteristics, given that a significant number have failed to adjust their setup and procedures to the child population. This study aimed to characterize smooth pursuit in children using child-friendly stimuli and procedures. Methods: Eye movements were recorded in 169 children (4–11 years) and 10 adults, while a customized, animated stimulus was presented moving horizontally and vertically at 68/s and 128/s. Eye movement recordings from 43 children with delayed reading, two with nystagmus, two with strabismus, and two with unsuccessful calibration were excluded from the analysis. Velocity gain, proportion of smooth pursuit, and the number and amplitude of saccades during smooth pursuit were calculated for the remaining participants. Median and quartiles were calculated for each age group and pursuit condition. ANOVA was used to investigate the effect of age on smooth pursuit parameters. Results: Differences across ages were found in velocity gain (68/s P , 0.01; 128/s P , 0.05), as well as the number (128/s P , 0.05) and amplitude of saccades (128/s P , 0.05), for horizontal smooth pursuit. Post hoc tests showed that these parameters were different between children aged 7 or younger and adults. No significant differences were found across ages in any smooth pursuit parameter for the vertical direction (P . 0.05). Conclusions: Using child-friendly methods, children over the age of 7 to 8 years demonstrated adultlike smooth pursuit. Translational Relevance: Child-friendly procedures are critical for appropriately characterizing smooth pursuit eye movements in children., Peer Reviewed, Postprint (published version)

Accommodative response and its possible role in myopia development has been explored through the study of the microfluctuations of accommodation, which are commonly divided in high (1.0 to 2.3 Hz) and low (0.1 to 0.6 Hz) frequency components. Previous research efforts have evidenced that a certain percentage of the amplitude of microfluctuations seems not to originate in the accommodative response. We aimed to develop and test a new approach to reduce this non-accommodative noise. For this purpose, ten healthy participants were enrolled to determine the difference between the amplitude of microfluctuations at near and distance for each range of frequencies, which was defined as the relative amplitude of microfluctuations. The findings support the exploration of the relative rather than absolute values of the amplitude of microfluctuations to better understand the contribution of both accommodative and non-accommodative factors to microfluctuations., Postprint (author's final draft)

This is the peer reviewed version of the following article: Ramon, C. , Cardona, G. , Biarnés, M. , Ferraro, L. L. and Monés, J. (2019), Longitudinal changes in outer nuclear layer thickness in soft drusen and reticular pseudodrusen. Clin Exp Optom, 102: 601-610. doi:10.1111/cxo.12894, which has been published in final form at https://doi.org/10.1111/cxo.12894. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions., Background: Drusen are seen in the early and intermediate stages of age-related macular degeneration. A retrospective, 2-year observational study at a tertiary centre was designed to assess outer nuclear layer thickness in different types of drusen. Methods: Patients over 50 years with predominant soft drusen or reticular pseudodrusen were included in the study. Fundus photography, infrared, fundus autofluorescence and spectral domain optical coherence tomography were performed at baseline, years 1 and 2. Outer nuclear layer thickness was measured in the nine Early Treatment Diabetic Retinopathy Study subfields, and the rate of thinning was determined using generalized estimating equations models. Results: Data were analysed from 17 eyes with soft drusen and 9 eyes with reticular pseudodrusen. Greater outer nuclear layer thinning was seen overall and in all subfields in reticular pseudodrusen as compared to soft drusen, with statistically significant differences found mostly in superior and nasal subfields of ring 2. The outer nuclear layer was 5-12 µm thinner in eyes with reticular pseudodrusen, and the rate of thinning was greater in eyes with reticular pseudodrusen in the outer superior subfield. Conclusions: In the present sample, outer nuclear layer thickness was consistently lower in patients with reticular pseudodrusen compared with soft drusen, irrespective of subfield location. These structural findings may contribute to explain the functional abnormalities observed in patients with reticular pseudodrusen., Peer Reviewed, Postprint (author's final draft)

Postprint (author's final draft)

Los videojuegos son una forma de entretenimiento para todas las edades. Existen muchos tipos de diferente género y plataforma. Aunque su uso es objeto de debate entre profesionales, los videojuegos catalogados como de acción se están usando como tratamiento para potenciar varias habilidades visuales, así como la percepción visual, ambliopía y dislexia según indican estudios de investigación. La tendencia a usar cada vez más esta forma de entretenimiento como herramienta terapéutica hace que sea más interesante conocer qué tipos de videojuegos pueden tener beneficios en el sistema visual y qué estudios existen al respecto., 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., Peer Reviewed, Postprint (author's final draft)

Postprint (author's final draft)

Background In high-income countries, the prevalence of blindness and visual impairment is higher among women, regardless of age although the mechanisms that produce these gender inequalities are not well understood. The objectives of this study were to analyse gender inequalities in the prevalence of blindness and visual impairment, age of onset, diagnosed and undiagnosed status and related eye diseases among visually impaired individuals. Methods Data were obtained from the 2008 Spanish Survey on ‘Disability, Personal Autonomy and Dependency Situations’ (n = 213 626) participants 360 blind (160 men and 200 women), and 5560 with some visual impairment (2025 men and 3535 women). The prevalence of blindness and visual impairment, age of onset of visual impairment and diagnosed and undiagnosed eye diseases was calculated. Hierarchical multiple logistic regression models were fit to test gender differences. Results Women were more likely to report visual impairment (crude OR = 1.6 [95% CI: 1.56–1.74]). Prevalence of diagnosed cataract was higher among visually impaired women (crude OR = 1.4 [95% CI: 1.25–1.67]) whereas undiagnosed eye disease (crude OR = 0.7 [95% CI: 0.64–0.81]) or diagnosed glaucoma (aORsex = 0.8 [95% CI: 0.65–0.93]) were more frequent among visually impairment men. These associations were not explained by age or educational level. Conclusions Strong gender inequalities were observed, with a higher prevalence of visual impairment and related cataracts among women, which could be related to gender inequalities in access to health care, and undiagnosed eye disease and related glaucoma among men, which could be related to their gender socialization resulting in less frequent and effectively use of health care services., Postprint (author's final draft)

Aims: To describe the experience of parents caregiving children with visual impairment (VI), to determine how their quality of life (QoL) is assessed, and to summarize QoL indicators through a review of the literature. Methods: A thematic search through PubMed, PsycINFO, ProQuest and ERIC databases was performed of articles published in English in peer-reviewed journals between 1996 and 2016. Publications were included if they referred to both children or adolescents with VI and their parents, or the family context. The complete selection process disclosed 37 papers suitable for review. Results: Researchers mainly used ad hoc interviews and questionnaires to investigate this topic. Two specific tools, the CarCGQoL (congenital glaucoma) and the OTI (congenital cataract), were identified. Most of the information collected referred to the parents' opinion concerning professional services, their needs and worries, the impact of VI on their emotional well-being and the strategies to assist parents to cope and adjust to the situation. Conclusions: The experience of caring for a child with VI is mainly influenced by psychosocial factors. Information and guidance to understand the child’s visual condition are insufficient, and the available resources reinforce concerns of caregivers regarding the child's opportunities, expressed as negative emotional reactions., Postprint (author's final draft)

We present a review on the visual ability to discriminate ¿ ne details of moving objects (DVA: Dynamic Visual Acuity), showing the most relevant differences, which have been attributed to this visual capacity in comparison to SVA (static visual acuity). It is known that the correlation between SVA and DVA is low. Moreover, when DVA is measured, not only the minimum spatial separation that the visual system can resolve is evaluated, but also the functionality of the oculomotor system. Therefore, assessing DVA also involves measuring the ability of the eye to actively seek information. Nowadays, it is known that DVA is one of the best indicators of success in certain sports specialties (table tennis, baseball, etc...) and that it negatively correlates with accident rates in traf¿ c scenarios. The investigated factors that produce a signi¿ cant reduction in dynamic spatial resolution are: the speed of the stimulus, affecting both vertical and horizontal trajectories; the stimulus exposure time; ambient illumination; reduction in contrast and subject age. Moreover, it has been veri¿ ed that this visual capacity is likely to improve with training., Postprint (published version)

Purpose: To explore anterior segment changes with keratoconus onset and progression to determine whether structural changes are predominantly corneal, limbal or both. To investigate these changes in different corneal meridians. Method: Eighty-four eyes with keratoconus and 49 healthy eyes were included in the study. Eyes with keratoconus were divided in two groups according to the Amsler-Krumeich classification: stage I and stages II-IV. Scheimpflug images at three different meridians were used to evaluate the following parameters: anterior chamber depth from the endothelium (ACD_end) and corneal thickness (CT) (software provided), anterior chamber depth (ACD) and sagittal depth (SAGT) from the epithelium, and distance from the end point of SAGT to the anterior surface of the lens (DL) (measured manually), and [ACD – CT] and [SAGT – CT] (calculated). Changes in these parameters with ocular condition and meridian were analysed. Results: Statistically significant larger values were found of ACD (p=0.012) and DL (p=0.016) with keratoconus onset and progression, with no differences in SAGT values. Besides, [ACD – CT] and [SAGT – CT] were significantly larger in keratoconus eyes (p<0.001 and p=0.003, respectively). Significant differences (all p<0.001) were found in SAGT, [SAGT – CT] and DL among meridians. Changes in these parameters with keratoconus onset and progression were similar in all meridians. Conclusion: Considering the results from the three meridians under investigation, it may be concluded that keratoconus onset has an impact on the anterior segment as a whole and not only on corneal structures. The DL distance is a useful parameter to describe limbal changes in keratoconus., Postprint (author's final draft)

Purpose: This study presents a two-degree customized animated stimulus developed to evaluate smooth pursuit in children and investigates the effect of its predetermined characteristics (stimulus type and size) in an adult population. Then, the animated stimulus is used to evaluate the impact of different pursuit motion paradigms in children. Methods: To study the effect of animating a stimulus, eye movement recordings were obtained from 20 young adults while the customized animated stimulus and a standard dot stimulus were presented moving horizontally at a constant velocity. To study the effect of using a larger stimulus size, eye movement recordings were obtained from 10 young adults while presenting a standard dot stimulus of different size (1° and 2°) moving horizontally at a constant velocity. Finally, eye movement recordings were obtained from 12 children while the 2° customized animated stimulus was presented after three different smooth pursuit motion paradigms. Performance parameters, including gains and number of saccades, were calculated for each stimulus condition. Results: The animated stimulus produced in young adults significantly higher velocity gain (mean: 0.93; 95% CI: 0.90-0.96; P = .014), position gain (0.93; 0.85-1; P = .025), proportion of smooth pursuit (0.94; 0.91-0.96, P = .002), and fewer saccades (5.30; 3.64-6.96, P = .008) than a standard dot (velocity gain: 0.87; 0.82-0.92; position gain: 0.82; 0.72-0.92; proportion smooth pursuit: 0.87; 0.83-0.90; number of saccades: 7.75; 5.30-10.46). In contrast, changing the size of a standard dot stimulus from 1° to 2° did not have an effect on smooth pursuit in young adults (P > .05). Finally, smooth pursuit performance did not significantly differ in children for the different motion paradigms when using the animated stimulus (P > .05). Conclusions: Attention-grabbing and more dynamic stimuli, such as the developed animated stimulus, might potentially be useful for eye movement research. Finally, Peer Reviewed, Postprint (author's final draft)