Search

Purpose: To investigate the relationship between digital screen time and the development and progression of myopia during the 2019 coronavirus disease (COVID-19) pandemic. Methods: Children aged 7–18 years who had regular refractive measurement follow-ups before and after the COVID-19 pandemic were included in the study. They were divided into two groups according to their initial refractive status, emmetropic and myopic. The relationship between spherical equivalent refraction (SER) changes and digital screen time before and after the pandemic was analyzed. Results: A total of 255 children were included in the study. During the pandemic in the emmetropic group, digital screen time increased by 5.98 ± 2.13 h/day, and the mean SER decreased from − 0.02 to − 0.55 D (p < 0.001). During the pandemic in the myopic group, the digital screen time increased by 6.25 ± 2.36 h, and the mean SER decreased from − 1.82 to − 2.72 D (p < 0.001). A significant correlation was found between the increase in digital screen time and the change in SER in the emmetropic and myopic groups (r = − 0.261, p = 0.015, r = − 0.269, p = 0.001, respectively). Conclusion: Increased digital screen time during the COVID-19 pandemic is associated with a myopic shift in emmetropic children and myopic progression in myopic children. As a result of COVID-19, increasing cases of myopia should be addressed as a public health concern. [ABSTRACT FROM AUTHOR]

Purpose: This paper discusses the accommodative relaxation of myopic adults using a simple double-mirror design. This optical design can extend the viewing distance to 2.285 m and can magnify the image up to 3.386 times, and it results in the accommodative relaxation of a single human eye. By using this optical design, accommodative relaxation may improve eye fatigue and, furthermore, it may delay the progression of myopia. Method: This study recruited 32 subjects with an average age of 20.8 ± 0.95 years old. After an examination of their refractive status, disposable contact lenses with a corresponding refractive error were fitted, and the dynamic accommodative response and change in pupil size were measured by using an open-field autorefractor. The subjects gazed at two different viewing distances. First, they gazed at a real object, which was placed 0.4 m in front of them. Second, the subjects gazed at a virtual image through a double-mirror system at a distance of 2.285 m. The dynamic accommodative responses and pupil size data were collected under these two viewing distance conditions. Results: When the subjects gazed at a real object that was 0.4 m away, or a virtual image that was 2.285 m away, the mean value of the accommodative response was 1.69 ± 0.31 D or 0.11 ± 0.05 D, and the pupil size was 3.79 ± 0.49 mm or 4.09 ± 0.72 mm, respectively. The accommodative response decreased, and the pupil size increased when using the double-mirror system, and therefore, accommodative relaxation can be achieved by using this new optical design. Conclusions: In the present study, we first successfully proposed a simple optical design to relax the accommodation, and the fluctuations of the accommodation response were stable, with an extended viewing distance of 2.285 m. This design may be applied for the improvement of visual function in applications such as the reduction of asthenopia and the control of myopia. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the association between potential risk factors for myopia and its progression in young adult Taiwanese men. Methods: A survey of male military conscripts (aged 18-24 years) was conducted from February 2010 to March 2011 in Taiwan. Participants underwent comprehensive eye examinations, including measurements of axial length and corneal radius by optical biometry and non-cycloplegic autorefraction. Participants also provided self-reported progression of myopia and information regarding potential risk factors, including age, parental myopia, educational level, close work, outdoor activities, and urbanization. Results: Of 5145 eligible participants, 5048 (98.11%) provided refraction and questionnaire data; 2316 (45.88%) of the 5048 also had biometric measurements. The prevalence of myopia was 86.1% in this group, with a mean refractive error of −3.66 diopters (D). Of the 5048 participants, 1376 (27.3%) had experienced progression of their myopia during the past year. There were trends for a higher prevalence of myopia among older participants ( p = 0.014), those with a history of parental myopia ( p < 0.001), higher levels of education ( p = 0.001), increased time spent reading ( p < 0.001), less time outdoors ( p = 0.003), and higher levels of urbanization ( p = 0.010). However, only parental myopia, close work, and higher urbanization levels were significantly associated with self-reported progression of myopia. Conclusion: Older age, parental myopia, higher educational level, close work, fewer outdoor activities, and higher urbanization level were associated with the prevalence of myopia in Taiwanese men. [ABSTRACT FROM AUTHOR]

The article provides information on a medical study related to progression of myopia in medical students due to genetic predisposition. Topics discussed include visual stress arising from refractive errors and nonsignificant growth of refractive power, degeneration during glaucoma, and genetic syndromes.