Evaluación de la Agudeza Visual Dinámica: una aplicación al contexto deportivo

The importance of vision in life is unquestionable. It is because of this that optometry, as a science of vision focused in measurement and analysis of visual function, has been developing techniques and instruments to evaluate its functionality in various contexts.Sport has become a social phenomenon, as evidenced by an increasing trend towards active participation, both professionally and recreationally. In order to enhance athletic performance, many have looked towards the sciences (medicine, biomechanics, psychology) for answers. With the specialization of sports vision, optometry has been particularly useful. The importance of the science of vision relating to sports is easily justified by considering that, in general, vision plays a dominant role in athletic success since the majority of external stimuli that athletes have to react to come through the visual system.One of the most critical areas that Sports Vision incorporates is the specific screening of visual capacities related to sports performance. If we consider the dynamic characteristics of most sporting modalities that generally involve constant environmental changes, sudden and fast movements of players and ball, speed, etc., we have to accept the premise that action sports require visual performance evaluation that is different from normal vision testing, since routine testing only samples static vision. Assessment of specific sports-related visual abilities includes peripheral vision, visual reaction time or dynamic visual acuity. In reference to the evaluation of dynamic visual acuity, defined as the ability to resolve a target under conditions of relative motion between the observer and the test stimulus, it must be noted that methods developed to date for its measurement have not been, in general, psychometrically validated, and are too cumbersome and unwieldy to find a place in clinical practice or in field situations. This lack of proper equipment explains much the difficulty of establishing objective, precise and reliable measurements of a visual skill, considered, not only from the sporting context but also from road safety or aircraft operating, as one of the most predictive of real-world task performances, especially in dynamic conditions."Additionally, the need to improve our daily work giving visual attention to elite athletes in the Olympic Training Centre in Sant Cugat del Vallés has led us to develop this doctoral dissertation, with the design of the DinVA 3.0., a computer assisted test for the measurement of dynamic visual acuity. The efficacy of our instrument has been supported by four experimental studies. The first three, included into the psychophysics context, have allowed us to find the legitimacy of the DinVA test measurement by establishing its construct validity, as well as internal and temporal consistency. The last experiment is a differential study where we compared the results of dynamic visual acuity obtained by a sample of elite water polo players and a group of totally sedentary students of Optometry.The obtained results have shown that speed, contrast and direction of displacement of the stimulus significantly affect dynamic visual acuity, supporting the construct validity of the DinVA3.0.Additionally, we have verified that our instrument to measure dynamic visual acuity has a high degree of internal validity, as well as a high test-retest reliability of the obtained measures.Finally, we have been able to establish that athletic training seems to improve dynamic visual acuity.In conclusion, with this doctoral dissertation we aim at offering both, clinicians and researchers, a standardized and typified instrument that allows a solid and specific measure of dynamic visual acuity depending on the application context. It is easy to use, offers the possibility of training, and does not require more equipment than something so common and ubiquitous as a computer.Postprint (published version

Repeatability and reproducibility of Cobra HD fundus camera meibography in young adults with and without symptoms of dry eye

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 0.89 for both eyelids, examiners and experimental sessions.Conclusions: The Cobra HD fundus camera demonstrates good repeatability, reproducibility and low WSV, and is a reliable clinical instrument for meibography.Peer ReviewedPostprint (published version

Topical review of the relationship between contact lens wear and meibomian gland dysfunction

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 ReviewedPostprint (author's final draft

Topical review: optometric considerations in sports vs. e-sports

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 ReviewedPostprint (author's final draft

Dynamic Visual Acuity

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

Effective Visual Field Rehabilitation in Homonymous Hemianopia by Attaching Binocular Prisms to Lenses

Postprint (published version

Effects of transient blur and VDT screen luminance changes on eyeblink rate

Purpose A study was designed to evaluate the efficacy of three different strategies aiming at increasing spontaneous eyeblink rate (SEBR) during computer use. Methods A total of 12 subjects (5 female) with a mean age of 28.7 years were instructed to read a text presented on a computer display terminal during 15 min. Four reading sessions (reference and three “blinking events” [BE]) were programmed in which SEBR was digitally recorded. “Blinking events” were based on either a slight distortion of the text characters or on the presentation of a white screen instead of the text, with or without accompanying blinking instructions. All BE had a duration of 20 ms and occurred every 15 s. Participants graded the intrusiveness of each BE configuration, and the number of lines participants read in each session was recorded. Results Data from 11 subjects was analysed. A statistically significant difference in SEBR was encountered between the experimental configuration consisting on a white screen plus blinking instructions (7.8 blinks/min) and both reference (5.2 blinks/min; p = 0.049) and white screen without blinking instructions (4.8 blinks/min; p = 0.038). All three BE had superior levels of intrusiveness than reference conditions, although the performance of participants (line count) was not compromised. Conclusions The joint contribution of white screen and blinking instructions has been shown to result in a short term improvement in blinking rate in the present sample of non-dry eye computer users. Further work is necessary to improve the acceptance of any BE aiming at influencing SEBR.Preprin

Comitant strabismus etiology: extraocular muscle integrity and central nervous system involvement—a narrative review

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 implications CNS etiology has on strabismus treatment.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature.Peer ReviewedPostprint (published version

Apuntes de psicología en atención visual

2012/201

Estudio de la función visual de una población de deportistas de élite

En el contexto de la optometría deportiva encontramos una cierta controversia sobre si las prestaciones visuales de los deportistas son superiores a las de la población sedentaria. La mayor parte de los estudios en este campo se han dirigido a analizar las habilidades visuales específicas de cada disciplina deportiva. En el presente trabajo hemos evaluado los aspectos más básicos de la función visual (anamnesis, agudeza visual, refracción, acomodación, binocularidad y dominancia oculomanual) de una muestra de 536 deportistas de élite de 17,4 ± 3,7 años, residentes en el CAR de Sant Cugat del Vallès, para determinar su nivel de desarrollo y compararlo, por una parte, entre los participantes de las diversas modalidades deportivas estudiadas y, por otra, con la población sedentaria, a partir de datos previamente publicados. Los resultados obtenidos muestran que el 28 % de los deportistas evaluados presentaba síntomas visuales y/o oculares y un 18,3% utilizaba neutralización óptica para el deporte. Respecto a la refracción, el 78,4 % era emétrope, el promedio del ojo derecho se sitúa en –0,15 ± 1,05 D. En cuanto al punto próximo de convergencia y la flexibilidad acomodativa, un 95,6 % y un 70,8%, respectivamente, superan los valores normativos. En algunas modalidades como el golf se invierten los porcentajes de dominancia oculomanual determinados para la población en general. La comparación entre deportes evidencia la superioridad visual de los pentatletas por encima del resto. There is some controversy in sports optometry over whether the visual performance of athletes is better than that of the sedentary population. Most of the studies in this field have involved analysing the specific visual skills of each sport. In this paper we have evaluated the most basic aspects of visual function (anamnesis, visual acuity, refraction, accommodation, binocularity and hand-eye dominance) of a sample of 536 elite athletes aged 17.4 ± 3.7 years resident at the High Performance Centre in Sant Cugat to determine their level of development and compare it firstly with participants in the various sports studied and secondly with the sedentary population using previously published data. The results show that 28% of the athletes tested had visual and/or eye symptoms and 18.3% used optical neutralisation for sport. With respect to refraction 78.4% presented emmetropia with the average of the right eye at -0.15 ± 1.05 D. As for the near point of convergence and accommodative flexibility, 95.6% and 70.8% respectively exceeded the regulatory values. In some sports such as golf the hand-eye dominance percentages for the general population are reversed. The comparison between sports evidences the visual superiority of pentathletes above the rest.Postprint (published version