We induced and evaluated different levels of retinal-image degradation using Bangerter foils and fog filters. We found increased straylight and an important deterioration in visual performance, assessed by means of visual acuity, contrast threshold, and visual discrimination capacity. Bangerter foils induced forward scattering levels comparable to those observed in mature to severe cataracts, with an important impact of halos and starbursts. Fog filters induced lower levels of intraocular scattering, although luminous veils and circular halos were reported. The visual disturbance index positively correlated with intraocular scattering and straylight. Our results show retinal-image quality has an important influence on night-vision performance.

Purpose: Myopia has emerged as a significant public health concern. Effective methods have now been developed to delay its onset and progression. However, this information may not be reaching parents, and they are key players in terms of implementing the necessary preventive measures. This study investigated parental awareness of myopia, its implications and the strategies available for controlling it. Methods: A self‐administered online survey was distributed to parents of children 6–16 years of age. To be eligible to respond, their child had to be myopic or at risk of developing myopia due to family history. Results: A total of 330 parents completed the survey, of which 321 were included for analysis. Sixty‐seven percent of respondents had at least one myopic son/daughter, and most were between −1.00 and −1.75 D. Among parents of myopic children, 20.9% thought that their child's myopia progressed moderately. Sixty‐seven percent of parents had a significant level of concern about the progression of the myopia and felt that it was caused mainly by the use of electronic devices and genetics. A generalised linear model showed that parental concern was significantly predicted by the perception of evolution ( p < 0.001) and the number of known health‐related consequences ( p < 0.001). Almost 40% of parents were unaware of the existence of myopia control strategies. Relatives and eye care practitioners are the main sources of information. The most well‐known myopia control strategy was myopia control soft contact lenses (29.2%), although the option that most parents would opt for was spectacles with peripheral defocus lenses (47.1%). The selection of a contact‐lens‐based myopia control method correlated significantly with the age of the children ( p < 0.001). Conclusions: Society in general and parents in particular need more information about myopia, its consequences and the options available for its control. Eye care practitioners play an important role in this issue.

Mental health concerns have emerged at the university level, with the psychological well-being of students being increasingly affected. This cross-sectional study investigated the proportion of university students having anxiety, and its effects on their visual function and symptomatology. We included 41 students (26.1 ± 4.8 years), and their visual function was assessed through several tests to produce a general visual performance index (VPI). The visual symptomatology was studied using the Conlon Visual Discomfort Survey and the Quality of Vision (QoV) questionnaire. The students were classified into two groups according to the Generalized Anxiety Disorder Screener (GAD-7) test (“no anxiety” and “anxiety” groups). The visual function evaluation indicated significantly worse VPI in the anxiety group (p = 0.047). These students also showed significantly higher scores in the Conlon survey (p = 0.004) and two subscales of the QoV questionnaire: symptom severity (p = 0.041) and symptom bothersomeness (p = 0.013). Moreover, the multiple linear regression model showed a significant association between visual discomfort according to the Conlon questionnaire and the level of anxiety (r = 0.405; R² = 0.164; B = 0.405; p = 0.012). It is important to study the influence of psychological factors on vision, not only for refractive error, but also for binocular and accommodative disorders.

Purpose: To assess binocular visual performance by means of binocular summation on visual function after inducing monocular forward scattering, and to study the influence of interocular differences on ocular parameters. Methods: Seven young healthy subjects were recruited. Four Bangerter foils and five fog filters were used to induce monocular forward scattering. To analyse the impact of the scatter, visual acuity, contrast sensitivity, visual discrimination capacity and distance stereoacuity were measured binocularly with the filter placed over the dominant eye. Additionally, interocular differences were calculated for four ocular parameters: the Objective Scatter Index (OSI), Strehl ratio (SR), modulation transfer function cut‐off (MTF cut off) and straylight (log[s]). Binocular summation was determined for these visual functions. Results: A statistically significant deterioration in visual acuity, contrast sensitivity and stereoacuity was seen for all of the filter conditions with respect to the natural state (baseline), with the largest change being recorded for the Bangerter foils. Similarly, the interocular difference for the three retinal image quality parameters (OSI, SR and MTF cut‐off) and log(s) increased significantly for the Bangerter foil condition, but not for the fog filters (except log(s)). Binocular summation declined gradually with the Bangerter foils, but not for the fog filters. Statistically significant correlations were found, that is, the greater the interocular differences, the lower the binocular summation of the visual functions and the greater the distance stereoacuity. Conclusion: Increased forward scattering in the dominant eye resulted in interocular differences, which reduced the overall binocular visual performance, including the binocular summation of several visual functions and distance stereoacuity. The results suggest that marked interocular differences in ocular parameters should be avoided in cases of ocular pathology, amblyopia and emmetropisation procedures (such as refractive surgery) or a monovision correction for presbyopia.

Purpose: Cannabis is the most widely consumed illicit drug worldwide. It has been suggested that cannabis could generate blurred vision during reading tasks. The goal of this study was to objectively assess the acute effects of smoking cannabis on the dynamics of ocular accommodation. The influence of other factors, including target distance and the direction of accommodation, as well as personal characteristics, were also analysed. Methods: Nineteen young people who were occasional cannabis users participated in the study (mean age 22.53 [3.12] years). Their usage profiles were evaluated by means of the Cannabis Use Disorders Identification Test‐revised (CUDIT‐r). The dynamics of the accommodative response were evaluated using an open‐field auto refractor (Grand Seiko WAM‐5500). The participants completed two different experimental sessions, one week apart, and in random order (baseline session and after smoking cannabis). During these sessions, the amplitude of the response (D), mean velocity (D/s), peak velocity (D/s), response time (s), accommodative lag (D) and accommodation variability (D) were measured. Results: The results indicated that cannabis use had a significant main effect on the mean accommodation/disaccommodation velocity ( F _1,13 = 7.21; p = 0.02; = 0.396). Cannabis consumption also interacted significantly with other factors. Response time showed a significant two‐way interaction between condition × target distance ( F _1,13 = 11.71; p = 0.005; = 0.474) and condition × accommodation direction ( F _1,13 = 8.71; p = 0.01; = 0.401). For mean velocity, two‐way interactions were found between condition × age ( F _1,13 = 6.03; p = 0.03; = 0.354), condition × CUDIT‐r score ( F _1,13 = 6.03; p = 0.03; = 0.356) and condition × target distance ( F _1,13 = 7.20; p = 0.02; = 0.396). Conclusions: These findings suggest that cannabis use can alter the accommodation process, although further studies should be carried out to explore the role of attention deficits. According to these results, certain daily activities that depend on an accurate accommodative function may be affected by cannabis use.

The aim of this study was to analyse the relationship between fine motor skills (FMSs) and visual performance. Thirty young participants with normal binocular vision performed five fine motor tasks: Purdue, Grooved, and O’Connor pegboards, a needle threading task, and a water pouring task, which were characterised by the time taken to complete the task, the number of pegs inserted, the error made in pouring the water, and the volume spilled. To evaluate visual performance, near visual acuity, near contrast sensitivity (CS), and disability glare were assessed. Fine motor skills and visual performance were assessed under monocular and binocular viewing conditions. An overall visual performance score (OVPS) and an overall fine motor skills score (OFMSS) were calculated. All visual functions measured binocularly were better than in monocular conditions, and all FMSs tasks were performed worse monocularly than binocularly (p < 0.001), except for the error made in the water pouring task (p = 0.024). There was a positive correlation between OVPS and OFMSS (rho = 0.329; p = 0.010). The regression model showed that the OFMSS can be predicted by age and CS at 21.3%. Individuals with normal binocular vision and better near visual function exhibit superior fine motor abilities. CS stands out as the visual function that has the greatest bearing on the performance of FMSs.