Use of digital displays and ocular surface alterations

Aunque nuestra comprensión de los efectos del uso de dispositivos electrónicos sobre la superficie ocular ha aumentado considerablemente desde el inicio de siglo, varias preguntas importantes siguen sin respuesta. Asimismo, los avances tecnológicos y la aparición de nuevas formas de dispositivos digitales hacen necesaria una investigación continua. Esta tesis doctoral presenta un total de 12 estudios independientes los cuales constituyen los pilares de este trabajo (Capítulos 4-15). En primer lugar, el Capítulo 4 tuvo como objetivo evaluar la asociación entre los factores de riesgo de la enfermedad de ojo seco (EOS) y el síndrome visual informático (SVI). Se llevó a cabo una encuesta online anónima en 851 estudiantes universitarios. Los participantes se clasificaron en dos grupos, en función de si padecían SVI (n = 628) o no (n = 222). Los resultados de este capítulo revelaron que varios factores de riesgo y condiciones de salud relacionados con el ojo seco están asociados con el SVI, por lo que las preguntas relacionadas con los factores de riesgo de la EOS pueden ser especialmente relevantes en pacientes que usan dispositivos electrónicos por períodos prolongados. Las anomalías del parpadeo constituyen uno de los principales mecanismos causantes de las alteraciones de la superficie ocular asociadas al SVI. Así pues, el objetivo del Capítulo 5 fue evaluar las diferencias en la cinemática del parpadeo durante la lectura con diferentes dispositivos electrónicos y una condición control sin dispositivo. Treinta y dos sujetos jóvenes fueron incluidos en este estudio. Se grabó el parpadeo de los participantes mientras leían en un ordenador portátil, una tableta, un libro electrónico (e-book), un teléfono móvil y durante una tarea control sin dispositivo. A juzgar por los resultados, la cinemática de parpadeo varía considerablemente entre los dispositivos y con respecto a una tarea de baja demanda cognitiva sin dispositivo. Estas diferencias probablemente se deban a la diferente forma en que se posicionan y usan las pantallas y a la demanda cognitiva de la tarea. En la actualidad existen diferentes tipos de dispositivos electrónicos y las diferencias en su naturaleza y en la forma en que se utilizan pueden condicionar su impacto sobre la superficie ocular. Teniendo en cuenta los resultados del Capítulo 5, el Capítulo 6 tuvo como objetivo comparar el impacto de dispositivos anteriores sobre la superficie ocular y la película lagrimal de 31 individuos jóvenes. El impacto más bajo se obtuvo con el teléfono móvil y el e-book, probablemente debido a un ángulo de mirada más bajo asociado con el uso del teléfono móvil y a las propiedades ópticas mejoradas del e-book. La instilación de lágrima artificial no mostró una mejora estadística en las variables de superficie ocular y película lagrimal para el mismo dispositivo, aunque atenuó los efectos del uso de la pantalla. Por otro lado, la identificación de individuos con predisposición a alteraciones de la superficie ocular con el uso de los dispositivos electrónicos puede proporcionar al especialista una ventaja considerable en el manejo de la condición. El Capítulo 7 tuvo como objetivo identificar qué parámetros de la superficie ocular y la película lagrimal son predictores del impacto del uso del ordenador sobre la superficie ocular. Para ello, se evaluó la superficie ocular de 82 estudiantes universitarios antes y después de leer con un ordenador durante 30 minutos. Los resultados mostraron que los participantes con mayores síntomas de ojo seco tenían más probabilidades de experimentar un mayor aumento de los síntomas con el uso del ordenador, mientras que un tiempo de ruptura lagrimal más largo y un mayor aumento del enrojecimiento conjuntival estaban asociados a una mayor reducción de la estabilidad lagrimal. Hoy en día los especialistas tienen una variedad de estrategias de manejo disponibles para prevenir o reducir los efectos del uso de dispositivos digitales sobre la superficie ocular. El Capítulo 8 tuvo como objetivo evaluar y comparar la efectividad de cuatro estrategias principales de manejo (instilación inicial de lágrima artificial, descanso breve, uso de un filtro de luz azul y control de parpadeo) para prevenir los efectos del uso de pantallas digitales sobre la superficie ocular, en una muestra de 47 individuos jóvenes. Los resultados de este capítulo evidenciaron que la instilación de lágrima artificial y el control del parpadeo son las mejores estrategias de manejo para prevenir los efectos del uso de pantallas digitales sobre la superficie ocular, mientras que el uso de un filtro de luz azul no ofrece beneficios apreciables. El uso de lentes de contacto es ampliamente reconocido como uno de los principales factores de riesgo para la EOS y, en consecuencia, para el SVI. Por ende, el Capítulo 9 tuvo como objetivo evaluar los posibles efectos sumatorios del uso de dispositivos electrónicos (ordenador y teléfono móvil) por periodos cortos y de lentes de contacto sobre la superficie ocular y la película lagrimal en una muestra de 34 adultos jóvenes. Los hallazgos de este capítulo indicaron que el uso de lentes de contacto no tiene efectos sumatorios sobre los signos y síntomas de ojo seco cuando se usan dispositivos digitales por períodos cortos y que la instilación de lágrima artificial es una estrategia eficaz para reducir el impacto del uso de dispositivos electrónicos en usuarios de lentes de contacto. Del mismo modo, el ojo seco se clasifica como el efecto adverso más común de la queratomileusis in situ asistida por láser (LASIK, del inglés laser in-situ keratomileusis), teniendo esta técnica la mayor incidencia y gravedad de EOS posoperatoria de todos los procedimientos queratorefractivos. El objetivo del Capítulo 10 fue evaluar el impacto del uso del ordenador por periodos cortos sobre la superficie ocular en personas intervenidas de LASIK, a fin de determinar si los pacientes post-LASIK tienen un mayor riesgo de ojo seco asociado al uso de dispositivos digitales. Se evaluaron los síntomas de ojo seco y la superficie ocular de 18 individuos jóvenes intervenidos de LASIK miópico y 18 controles, antes y después de realizar una tarea de 30 minutos utilizando un ordenador con y sin instilación inicial de lágrima artificial. En definitiva, el aumento de los síntomas de ojo seco y los síntomas de SVI reportados durante la tarea con el ordenador fueron similares entre ambos grupos de estudio. Los síntomas estuvieron acompañados por un empeoramiento significativo de los signos de ojo seco en el grupo LASIK. Por otro lado, la instilación de lágrima artificial fue eficaz para prevenir el empeoramiento de los signos y síntomas del ojo seco en ambos grupos poblacionales. El objetivo del Capítulo 11 fue evaluar la relación entre los síntomas oculares y la sensibilidad corneal a estímulos mecánicos y fríos en 52 usuarios frecuentes de ordenador, tras haberse reportado que períodos repetidos de estimulación de la superficie ocular por inestabilidad lagrimal pueden alterar la excitabilidad de los receptores corneales y su capacidad de respuesta a estímulos nuevos. Los umbrales de sensibilidad mecánica y al frío de la córnea central se determinaron en un ojo aleatoriamente seleccionado de cada participante utilizando el UNSW LJA (del inglés University of New South Wales Liquid Jet Aesthesiometer). Los usuarios de ordenador sintomáticos mostraron umbrales de sensibilidad al frío más bajos en comparación con los usuarios asintomáticos, lo que sugiere alteraciones en la función sensorial de la córnea en usuarios de ordenador con SVI. Asimismo, mayores síntomas de SVI, particularmente síntomas relacionados con el ojo seco, se asociaron con umbrales de excitación más bajos (hipersensibilidad) de las neuronas corneales a estímulos fríos. Teniendo en cuenta estos hallazgos, el Capítulo 12 tuvo como objetivo evaluar los posibles efectos del uso del ordenador durante periodos cortos sobre la sensibilidad de la córnea y analizar las asociaciones con posibles factores determinantes en una muestra similar de sujetos jóvenes. Las medidas de sensibilidad se tomaron antes y después de trabajar con un ordenador de sobremesa durante 1 hora en una tarea de libre elección. En base a los resultados de este capítulo, el uso del ordenador durante un periodo de una hora no tuvo ningún efecto sobre la sensibilidad de la córnea central a estímulos mecánicos y fríos. Además, los síntomas oculares y las variables demográficas no se asociaron con los cambios en la sensibilidad con el uso del ordenador. Debido al cambio significativo en el índice de refracción del aire a la película lagrimal, las anomalías en la película lagrimal pueden afectar notablemente a la calidad visual. Con esta premisa en mente, el objetivo del Capítulo 13 fue evaluar y comparar exhaustivamente los cambios en la función visual y la calidad óptica y de la película lagrimal en un grupo de trabajadores que usaban el ordenador como herramienta de trabajo (n = 40) y un grupo de trabajadores sin ordenador (n = 40) a lo largo de una jornada laboral normal. Según los resultados de este capítulo, aunque la agudeza visual se mantuvo sin cambios, varios aspectos de la función y la calidad visual disminuyeron durante un día de uso del ordenador. Estos cambios estuvieron acompañados de una mayor sintomatología de ojo seco y alteraciones de la película lagrimal, las cuales probablemente jugaron un papel fundamental. El SVI está muy influenciado por la demanda visual y la duración de la tarea. A los usuarios frecuentes de dispositivos digitales a menudo se les recomienda seguir la regla 20-20-20 (apartar la mirada de la pantalla durante al menos 20 s a un objeto distante situado a una distancia de al menos 20 pies tras 20 minutos de trabajo continuo), aunque con evidencia científica limitada. El objetivo del Capítulo 14 fue evaluar los beneficios visuales de tomar descansos regulares basados en esta popular regla de ergonomía visual. Para ello, se descargó en los ordenadores portátiles de 29 usuarios de ordenador sintomáticos un software informático (eyeblink, https://www.blinkingmatters.com/), modificado por el desarrollador para este estudio, que utilizaba la cámara web del ordenador para evaluar los descansos del usuario, la mirada y el parpadeo, y el cual emitía recordatorios personalizados de descansos basados en la regla 20-20-20. El SVI, la visión binocular y la superficie ocular se evaluaron antes y después de seguir la regla durante dos semanas y una semana tras su interrupción. Los resultados de este capítulo indicaron que la regla 20-20-20 es una estrategia eficaz para reducir los síntomas de SVI y ojo seco, aunque dos semanas no fueron suficientes para mejorar considerablemente la visión binocular o los signos de ojo seco. Por último, teniendo en cuenta los cambios globales en la educación y en los patrones de uso de la tecnología que surgieron tras el brote de coronavirus (COVID-19), el Capítulo 15 tuvo como objetivo evaluar los posibles efectos de cambiar a un formato de educación online sobre los síntomas de ojo seco y los factores de riesgo de la EOS. Para ello se llevó a cabo una encuesta online, transversal y anónima en 812 estudiantes universitarios. En general, asistir a clases online se asoció de forma independiente con tener síntomas de ojo seco. A pesar de una menor prevalencia de factores de riesgo de EOS, un mayor uso del ordenador estuvo detrás de la mayor sequedad ocular reportada por los estudiantes online.Although our understanding of the effects of digital display use on the ocular surface has increased considerably since the turn of the century, several major questions remain unanswered. Likewise, technological advances and the appearance of new forms of digital displays demand continuous research. This thesis presents a total of 12 independent studies that constitute the chapters of this work (Chapters 4-15). In the first place, Chapter 4 aimed to explore the association between digital eye strain (DES) and dry eye-related lifestyle and demographic factors. For this purpose, an anonymous online survey was carried out on 851 university students. Participants were classified into DES (n = 628) or non-DES (n = 222). The results of this chapter revealed that several dry eye-related risk factors and health conditions are associated with DES. Therefore, clinicians should acknowledge the relevance of triaging questions and dry eye disease (DED) risk factors when dealing with patients who view screens for extended periods. Blinking abnormalities make up one of the main DES-inducing mechanisms. Accordingly, the aim of Chapter 5 was to assess the differences in blinking kinematics between reading on different digital displays and a non-device control condition. Thirty-two young individuals were included in this study. The blinks of the participants were recorded while reading on a laptop computer, tablet, electronic reader (e-reader), and smartphone and in a non-device control condition. Judging by the results, blinking kinematics seem to vary considerably between displays and with respect to a non-device, low-demanding control condition. These differences could probably be attributed to differences in the way the displays are set up and used and the cognitive demand of the task at hand. Nowadays, numerous new kinds of digital displays have been developed and the differences in their nature and the ways in which they are set up and used may condition their impact on the ocular surface. Bearing in mind the results of Chapter 5, Chapter 6 aimed to compare the impact of the aforementioned digital displays on the ocular surface and tear film of 31 young individuals. According to the findings of this chapter, the lowest impact was obtained with the smartphone and the e-reader, probably due to a lower gaze angle associated with smartphone use and to the enhanced optical properties of the e-reader. The instillation of artificial tears did not show a statistical improvement in ocular surface and tear film variables for the same device, although it attenuated the effects of display use. On a different note, effective identification of individuals with a predisposition to the disruption of their ocular surface following display use can provide the practitioner with a considerable advantage in managing the condition. Chapter 7 aimed to identify which ocular surface and tear film characteristics are relevant predictors of the impact of computer use on dry eye signs and symptoms. For the purpose, the ocular surface of 82 undergraduate students was assessed at baseline and after they had read on a computer for 30 minutes. According to the results of this chapter, participants with greater dry eye symptoms were more likely to experience a greater increase in symptomatology following computer use, while a longer tear break-up time and a greater increase in conjunctival redness with computer use were associated with a greater reduction in tear stability. Nowadays, clinicians have a range of management strategies available to reduce or prevent the effects of digital display use on the ocular surface. Chapter 8 aimed to assess and compare the effectiveness of four main management strategies (instillation of artificial tears, taking a brief break, using a blue light screen filter, and blink control) for preventing the short-term effects of digital display use on dry eyes, in a sample of 47 young individuals. The results of this chapter showed that the instillation of artificial tears and blink control were the best management strategies for preventing short-term effects of digital display use on dry eyes, while using a blue light filter did not offer any benefits. Contact lens (CL) wear is widely recognised as one of the main risk factors for DED and consequently for DES. Accordingly, Chapter 9 aimed to evaluate the potential additive effects of short-term display use (computer and smartphone) and CL wear, in addition to the benefits of artificial tear instillation, on the ocular surface and tear film in a sample of 34 young volunteers. The findings of this chapter showed that CL wear has no additive effects on signs and symptoms of dry eye when using digital devices for short periods and that the instillation of artificial tears is an effective strategy for reducing the impact of display use in CL wearers. Similarly, dry eye is categorized as the most common adverse effect of laser in situ keratomileusis (LASIK) surgery, with this technique having the highest incidence and severity of postoperative DED of all kerato-refractive procedures. The aim of Chapter 10 was to assess the impact of short-term computer use on the ocular surface of individuals after LASIK in order to determine whether post-LASIK patients are at an increased risk of digital display-induced dry eye. The dry eye symptoms and ocular surface of 18 post-myopic LASIK, young individuals and 18 controls were evaluated before and after performing a 30-minute task on a computer with and without initial instillation of artificial tears. Overall, the increase in symptoms of dry eye and the symptoms of DES reported during the computer task were comparable between both study groups. Symptoms were accompanied by a significant worsening of dry eye signs in the LASIK group. In parallel, the instillation of artificial tears was effective in preventing the worsening of dry eye signs and symptoms in all cases. Repeated periods of ocular surface stimulation by tear film instability may alter the excitability of corneal receptors and their responsiveness to new stimuli. Accordingly, the aim of Chapter 11 was to evaluate the relationship between ocular symptoms and corneal sensitivity to mechanical and cold stimuli in 52 frequent computer users. Mechanical and cold sensation thresholds were determined at the central cornea of the randomly selected eye of each participant using the University of New South Wales Liquid Jet Aesthesiometer (UNSW LJA, UNSW, Sydney, Australia). Symptomatic computer users exhibited lower cold sensation thresholds compared to asymptomatic users, which suggests alterations in the corneal sensory function among computer users with DES. Likewise, greater symptoms of DES, particularly dry eye related symptoms, were associated with lowered excitation thresholds (hypersensitivity) of the corneal neurons to corneal cooling. Considering these findings, Chapter 12 aimed to evaluate the potential effects of short-term computer use on the sensitivity of the cornea to various stimuli and analyse associations with possible determinants in a similar sample of subjects. Sensitivity measurements were taken before and after working on a desktop computer for 1 hour in a freely chosen task. The results of this chapter indicate that short-term computer use had no effect on the sensitivity of the central cornea to mechanical and cold stimuli. Additionally, ocular symptoms and demographic variables were not associated with the changes in sensitivity following computer use. Due to the significant refractive index change from air to tear film, abnormalities to the tear film can impact visual quality in a significant way. Based on this premise, the aim of Chapter 13 was to thoroughly assess and compare the changes in visual function and optical and tear film quality in a group of computer workers (n = 40) and a group of non-computer workers (n = 40) throughout a normal working day. According to the results of this chapter, while visual acuity remained unchanged, several aspects of visual function and quality of vision declined over a day of intense computer use. DES is highly influenced by the visual demand and the duration of a given task. Based on this principle, frequent screen users are often advised to follow the 20-20-20 rule (look away from the screen for at least 20 s to a distant scene at least 20 feet away after every 20 minutes of continuous work), although with limited evidence. Accordingly, the aim of Chapter 14 was to evaluate the visual benefits of taking regular breaks based on this popular rule of visual ergonomics. To test the study hypothesis, bespoke computer software (eyeblink, https://www.blinkingmatters.com/), modified for the study by the developer, which employs the laptop webcam to assess user breaks, eye gaze and blinking, and which emits personalized reminders of breaks based on the 20-20-20 rule, was downloaded onto the laptops of 29 symptomatic computer users. DES, binocular vision and dry eye were assessed before and after two weeks of using the reminders and one week after the discontinuation of the strategy. The results of this chapter indicate that the 20-20-20 rule is an effective strategy for reducing DES and dry eye symptoms, although 2 weeks was not enough to considerably improve binocular vision or dry eye signs. Finally, considering the global changes in education and technology use patterns following the coronavirus (COVID-19) outbreak, the last study presented in this work, and described in detail in Chapter 15, aimed to assess the potential effects of switching to an online lecture format on dry eye symptoms and DED risk factors. For this purpose, an anonymous cross-sectional online survey was carried out on 812 university students. Largely, attending online lectures was independently associated with having dry eye symptoms. Despite a lower prevalence of DED risk factors, higher computer use is probably the reason behind the greater ocular dryness reported by online students

Presbyopia and the aging eye: Existing refractive approaches and their potential impact on dry eye signs and symptoms

Every part of the human body is subject to aging, including the eye. Increased prevalence of dry eye disease with age is widely acknowledged: aging threatens ocular surface homeostasis, altering the normal functioning of the lacrimal functional unit and potentially leading to signs and symptoms of dry eye. Parallelly, two additional degenerative processes take place within the crystalline lens, leading to presbyopia and cataractogenesis. With continuously increasing life expectancies both conditions are expected to impact society further. Correction strategies for presbyopia and cataracts either directly or indirectly challenge ocular surface additionally. On one hand, contact lens presbyopic correction has gained many adepts in recent years. Contact lenses disturb the normal structure of the tear film and interact negatively with the ocular surface eventually initiating the closed loop of inflammation vicious circle, similarly to dry eye. On the other hand, cataract and corneal refractive surgeries sever corneal nerves and disrupt corneal epithelium and ocular surface, further inducing dryness. In the present review we address the invasive nature of the different contact lens and refractive surgery correction strategies. In addition, we deeply discuss how contact lenses, cataract surgery and various types of corneal refractive surgical strategies play a role in inducing/worsening signs and symptoms of dryness in an aging population

Changes in visual function and optical and tear film quality in computer users

Purpose: To assess changes in visual function and optical and tear film quality in computer users.Methods: Forty computer workers and 40 controls were evaluated at the beginning and end of a working day. Symptoms were assessed using the Quality of Vision questionnaire (QoV), 5-item Dry Eye Questionnaire (DEQ--5) and Symptom Assessment in Dry Eye version II (SANDE II). Tear film quality was evaluated using the Medmont E300 dynamic corneal topography tool to measure the tear film surface quality (TFSQ), TFSQ area and auto tear break- -up time (TBUT). Optical quality was assessed by measuring high, low and total ocular aberrations with a Hartmann-Shack wavefront sensor. Visual performance was assessed by measuring photopic and mesopic visual acuity, photopic and mesopic contrast sensitivity and light disturbance.Results: Poorer DEQ-5, QoV and SANDE II scores were obtained in computer workers at the end of the working day compared with controls ( p = 0.19) or ocular aberrations were observed (p >= 0.09). Additionally, both light disturbance ( p = 0.07). In contrast, control subjects exhibited no decrease in any variable during the day.Conclusions: While visual acuity remained unchanged, several aspects of visual function and quality of vision decreased over a day of computer use. These changes were accompanied by greater dry eye symptoms and tear film changes, which are likely to have played a fundamental role. The present study provides insight into new metrics to assess digital eye strain.Conselleria d'Educacio, Investigacio, Cultura i Esport de la Generalitat Valenciana, Grant/Award Number: GV/2018/059; Spanish Ministry of Universities, Grant/Award Number: FPU17/0366

Comparison of the influence of corneo-scleral and scleral lenses on ocular surface and tear film metrics in a presbyopic population

PURPOSE: To assess and compare the effect of the corneo-scleral lenses (C-ScL) and scleral lenses (ScL) on tear film parameters and central corneal thickness (CCT) in healthy presbyopic subjects. METHODS: Thirty subjects wore two contact lenses (CLs), randomly assigned, of neutral power, but of different diameters, 12.7mm (C-ScL) and 18mm (ScL) and being equal in the others parameters: material (HS100) and centre thickness (0.29mm). At baseline, 20min after insertion and at 8h, the tear meniscus area (TMA) and CCT was measured (with optical coherence tomography) as well as tear osmolarity. RESULTS: TMA revealed statistical differences for both lenses at 20min (p<0.001), and also at 8h (p=0.003), being greater for the C-ScL. CCT showed statistical differences for both lenses at 20min (p=0.002), and also at 8h (p=0.001), being lower for the C-ScL. Osmolarity did not reveal statistical differences at 20min (p=0.29), while it was statistically different at 8h (p=0.03), being lower for the C-ScL. CONCLUSIONS: C-ScL lead to a lesser reduction in the TMA and a lower induced hypoxic stress than the ScL. Osmolarity levels remained within normal values across the day with no clinical difference between lenses. Both designs can represent a good optical platform for correcting presbyopia as well as protecting the ocular surface by vaulting the cornea

The effects of breaks on digital eye strain, dry eye and binocular vision:Testing the 20-20-20 rule

PURPOSE: To evaluate the benefits on the eyes of taking breaks based on the 20-20-20 rule. METHODS: Bespoke computer software using the laptop webcam to assess user breaks, eye gaze and blinking, and emitting personalized reminders of breaks based on the 20-20-20 rule, was downloaded onto the laptops of 29 symptomatic computer users. Digital eye strain (DES), binocular vision and dry eye were assessed before and after two weeks of using the reminders and one week after the discontinuation of the strategy. Binocular measurements included visual acuity, accommodative posture, stereopsis, fixation disparity, ocular alignment, accommodative facility, positive/negative vergences and near point of convergence. Symptoms were evaluated using the computer vision syndrome questionnaire, ocular surface disease index (OSDI), and symptom assessment in dry eye questionnaire (SANDE) versions one and two. Dry eye signs were assessed by measuring tear meniscus height, conjunctival redness, blink rate and incomplete blinking, lipid layer thickness, non-invasive keratograph break-up time, corneal and conjunctival staining and lid wiper epitheliopathy. RESULTS: A decrease in the duration of computer work and the duration of breaks, along with an increase in the number of breaks taken per day was observed as a result of the 20-20-20 rule reminders (p ≤ 0.015). No changes on any binocular parameter were observed after the management period (p ≥ 0.051), except for an increase in accommodative facility (p = 0.010). Dry eye symptoms and DES decreased with the rule reminders (p ≤ 0.045), although this improvement was not maintained one week after discontinuation (p > 0.05). No changes on any ocular surface and tear film parameter were observed with the rule reminders (p ≥ 0.089). CONCLUSIONS: The 20-20-20 rule is an effective strategy for reducing DES and dry eye symptoms, although 2 weeks was not enough to considerably improve binocular vision or dry eye signs

Systemic, environmental and lifestyle risk factors for dry eye disease in a mediterranean caucasian population

Objectives: To assess systemic, environmental and lifestyle risk factors for dry eye disease (DED) in a Mediterranean Caucasian population. Methods: A cross-sectional study was performed on 120 Caucasian participants aged between 18 and 89 years (47.0 ± 22.8 years). Medical history, information regarding environmental conditions and lifestyle, Ocular Surface Disease Index, Dry Eye Questionnaire-5, non-Invasive (Oculus Keratograph 5 M) breakup time, tear film osmolarity and ocular surface staining parameters were assessed in a single clinical session to allow DED diagnosis based on the guidelines of the Tear Film and Ocular Surface Society Dry Eye Workshop II Diagnostic Methodology Report. A multivariate logistic regression model was constructed including those variables with a p-value less than 0.15 in the univariate analysis. Results: A prevalence of 57.7 % for DED was found. No age differences were found between those with and without DED (U = 1886.5, p = 0.243). Nevertheless, the DED group had more females (X2 = 7.033, p = 0.008). The univariate logistic regression identified as potential risk factors for DED the following: female sex, sleep hours per day, menopause, anxiety, systemic rheumatologic disease, use of anxiolytics, daily medication, ocular surgery, poor diet quality, more ultra-processed food in diet, not drinking caffeine and hours of exposure to air conditioning per day. Multivariate logistic regression revealed that hours of sleep per day, menopause and use of anxiolytics were independently associated with DED (p ≤ 0.026 for all). Conclusions: DED is associated with systemic, environmental and lifestyle risk factors. These findings are useful to identify potentially modifiable risk factors, in addition to conventional treatments for DED

Systemic, environmental and lifestyle risk factors for dry eye disease in a mediterranean caucasian population

Objectives: To assess systemic, environmental and lifestyle risk factors for dry eye disease (DED) in a Mediterranean Caucasian population. Methods: A cross-sectional study was performed on 120 Caucasian participants aged between 18 and 89 years (47.0 ± 22.8 years). Medical history, information regarding environmental conditions and lifestyle, Ocular Surface Disease Index, Dry Eye Questionnaire-5, non-Invasive (Oculus Keratograph 5 M) breakup time, tear film osmolarity and ocular surface staining parameters were assessed in a single clinical session to allow DED diagnosis based on the guidelines of the Tear Film and Ocular Surface Society Dry Eye Workshop II Diagnostic Methodology Report. A multivariate logistic regression model was constructed including those variables with a p-value less than 0.15 in the univariate analysis. Results: A prevalence of 57.7 % for DED was found. No age differences were found between those with and without DED (U = 1886.5, p = 0.243). Nevertheless, the DED group had more females (X2 = 7.033, p = 0.008). The univariate logistic regression identified as potential risk factors for DED the following: female sex, sleep hours per day, menopause, anxiety, systemic rheumatologic disease, use of anxiolytics, daily medication, ocular surgery, poor diet quality, more ultra-processed food in diet, not drinking caffeine and hours of exposure to air conditioning per day. Multivariate logistic regression revealed that hours of sleep per day, menopause and use of anxiolytics were independently associated with DED (p ≤ 0.026 for all). Conclusions: DED is associated with systemic, environmental and lifestyle risk factors. These findings are useful to identify potentially modifiable risk factors, in addition to conventional treatments for DED

The effects of breaks on digital eye strain, dry eye and binocular vision: Testing the 20-20-20 rule

PURPOSE: To evaluate the benefits on the eyes of taking breaks based on the 20-20-20 rule. METHODS: Bespoke computer software using the laptop webcam to assess user breaks, eye gaze and blinking, and emitting personalized reminders of breaks based on the 20-20-20 rule, was downloaded onto the laptops of 29 symptomatic computer users. Digital eye strain (DES), binocular vision and dry eye were assessed before and after two weeks of using the reminders and one week after the discontinuation of the strategy. Binocular measurements included visual acuity, accommodative posture, stereopsis, fixation disparity, ocular alignment, accommodative facility, positive/negative vergences and near point of convergence. Symptoms were evaluated using the computer vision syndrome questionnaire, ocular surface disease index (OSDI), and symptom assessment in dry eye questionnaire (SANDE) versions one and two. Dry eye signs were assessed by measuring tear meniscus height, conjunctival redness, blink rate and incomplete blinking, lipid layer thickness, non-invasive keratograph break-up time, corneal and conjunctival staining and lid wiper epitheliopathy. RESULTS: A decrease in the duration of computer work and the duration of breaks, along with an increase in the number of breaks taken per day was observed as a result of the 20-20-20 rule reminders (p ≤ 0.015). No changes on any binocular parameter were observed after the management period (p ≥ 0.051), except for an increase in accommodative facility (p = 0.010). Dry eye symptoms and DES decreased with the rule reminders (p ≤ 0.045), although this improvement was not maintained one week after discontinuation (p > 0.05). No changes on any ocular surface and tear film parameter were observed with the rule reminders (p ≥ 0.089). CONCLUSIONS: The 20-20-20 rule is an effective strategy for reducing DES and dry eye symptoms, although 2 weeks was not enough to considerably improve binocular vision or dry eye signs

Effects of cataract surgery on blinking

Phacoemulsification cataract surgery significantly altered the blinking pattern of patients, with a reduction in the blink rate and an increase in the percentage of incomplete blinks, although blinking kinematics remained unvaried

Test B-Y glare

El material es un archivo ejecutable, que permite instalar una aplicación para evaluar un índice de estés frente al deslumbramiento, comparando medidas de agudeza visual previa y posterior al deslumbramiento con una fuente de luz externa (600 luxes). Las medida de agudeza visual se realiza con una tarea de discriminación de orientaciones (el paciente debe describir la orientación de una letra E de Snellen), con estímulos modulados a lo largo de la dirección azul-amarillo de l modelo de Boynton. Los estímulos incluidos en la aplicación no son configurables, y están calculados asumiendo los datos de caracterización colorimétrica de un monitor particular, y por tanto, el programa sólo puede proporcionar datos orientativos sobre los pacientes cuando se usa en otro dispositivo. Se incluye una pequeña base de datos, de pacientes jóvenes, con la que comparar a los distintos sujetos problema. El programa está todavía en proceso de desarrollo y validación.Este test se ha desarrollado gracias a la financiación proporcionada por el Vicerectorat de Polítiques de formació i Qualitat Educativa de la Universidad de Valencia