The ocular surface and blinking in children

Background: Ocular surface characteristics in children have not been as well investigated as in adults. Children’s digital device usage is rapidly increasing, and smartphones are the most commonly used device. The ocular surface impacts are unknown in children. In adults, use of digital devices induces ocular symptoms, adversely impacts blinking, and disrupts ocular surface homeostasis. Although blinking is integral to a healthy ocular surface, this is yet to be characterised in children, including the effects of digital devices. This thesis aims to characterise the ocular surface of children including blinking and to examine the impact of smartphone use on ocular surface homeostasis in children. Methods: The literature on ocular surface (symptoms, clinical indices, tear film function, blinking) of healthy children was reviewed and a meta-analysis of tear film stability and tear secretion was conducted. Cross-sectional studies of healthy school-aged children were conducted to examine the utility of commonly used adult-validated dry eye symptom questionnaires (SANDE, OSDI, NRS, OCI, DEQ-5, IOSS), and to characterise ocular surface clinical indices. This included blinking which was measured in situ using a novel eye tracking headset (Pupil Labs GmbH, Germany). The impact of one hour smartphone gaming on the ocular surface (including symptoms and blink parameters) of this paediatric population was examined with an intervention study. Blinking was also examined in situ under different conditions and tasks (reading from hard copy and on digital devices, conversation, walking) using the eye tracking headset in healthy adults. Repeatability of blink measurements (blink rate and interblink interval) in adults using the eye tracking headset was determined. Results: Ocular symptoms, tear film function and blinking were sparsely reported in children. The pooled mean by tear stability measurement methods in the meta-analysis were higher than previously reported in healthy adults while the pooled mean for tear secretion by methods were within the expected normal range for adults. Six existing dry eye questionnaires could be successfully used in paediatric eye care, and their repeatability was mostly comparable to that reported previously in adults. More time and assistance were at times required for younger children and specific terms such as ‘gritty’ and ‘foreign body sensation’ were not always well understood by younger children. The DEQ-5 and IOSS are recommended for use in younger age children. Blinking was associated with greater tear volume and worse meibomian gland expressibility but not digital device use, age, sex, or symptoms in children. One hour smartphone gaming led to increased symptoms of dryness, discomfort, and tiredness but did not impact tear film function. Blinking was rapidly reduced by a third within the first minute of gaming and this effect remained unchanged throughout one hour of gaming (p<0.001). Blink rate was consistently slower during all reading tasks compared to conversation (p≤0.002) and walking (p≤0.03), irrespective of task complexity, screen brightness, working distance or device used. Blinking could be reliably measured using a wearable eye tracking headset; the coefficient of repeatability for blink rate was ±12.4 blinks/min. Conclusions: This study established that existing dry eye questionnaires can be reliably used in children to examine the impact of challenges such as digital device use. An eye tracking headset reliably measured blink rate in situ in adults and detected differences in blinking during various real-life tasks. It was successfully used in children to measure blinking in situ showing an immediate and sustained slowing of blinking, evident after up to one hour of smartphone gaming. An hour of smartphone gaming worsened ocular comfort in children but did not appear to disturb the tear film. Given the ubiquitous use of smartphones by children, future work should examine whether effects reported herein persist or get worse over the longer term, potentially causing cumulative damage to the ocular surface. Blink amplitude and relationships with ocular surface clinical indices and digital device use may be explored using the methods established in this study

Photoaversion in inherited retinal diseases: clinical phenotypes, biological basis, and qualitative and quantitative assessment

Severe light sensitivity is a feature common to a range of ophthalmological and neurological diseases. In inherited retinal diseases (IRDs) particularly, this may be accompanied by significant visual disruption. These symptoms are extremely debilitating for affected individuals and have significant implications in terms of day-to-day activities. Underlying mechanisms remain to be fully elucidated. Currently, there are many assessments of photoaversion (PA), however, all have limitations, with quantitative measurement in particular needing further evaluation. To understand the complexities associated with photoaversion from different pathologies, qualitative and quantitative assessments of the light aversion response must be standardized. There is no treatment to date, and strategies to alleviate symptoms focus on light avoidance. With respect to IRDs, however, gene therapy is currently being investigated in clinical trials and promising and further treatments may be on the horizon. The better characterization of these symptoms is an important end point measure in IRD gene therapy trials

Mobile Technology in Allergic Rhinitis : Evolution in Management or Revolution in Health and Care?

Smart devices and Internet-based applications (apps) are largely used in allergic rhinitis and may help to address some unmet needs. However, these new tools need to first of all be tested for privacy rules, acceptability, usability, and cost-effectiveness. Second, they should be evaluated in the frame of the digital transformation of health, their impact on health care delivery, and health outcomes. This review (1) summarizes some existing mobile health apps for allergic rhinitis and reviews those in which testing has been published, (2) discusses apps that include risk factors of allergic rhinitis, (3) examines the impact of mobile health apps in phenotype discovery, (4) provides real-world evidence for care pathways, and finally (5) discusses mobile health tools enabling the digital transformation of health and care, empowering citizens, and building a healthier society. (C) 2019 American Academy of Allergy, Asthma & ImmunologyPeer reviewe

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