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Near work activity was estimates as risk factor of refractive error. This study aimed to analyze the association between near work activity and visucal acuity in junior high school students in Jatinangor. This study used cross-sectional method. Total of 147 subjects were screened for visual impairment and assessed for near work activities. Result showed total diopter-hours and time spent for each near work activity was less in group with visual acuity ≥ 6/18 than < 6/18 with no significant difference, except for playing games (p=0.018). In conclusion, near work activity does not have impact on visual acuity, except for playing games.

Convergence plays a fundamental role in the performance of near visual tasks. We measured the effect of two levels of convergence on anterior scleral thickness and shape in emmetropes, low to moderate myopes and high myopes.Forty-five healthy young adults aged between 18 and 35 years including 15 emmetropes, 15 low/moderate myopes, and 15 high myopes were recruited. Anterior segment optical coherence tomography and eye surface profilometry were used to evaluate the anterior scleral thickness (nasal only, n = 42) and shape (n = 40), before and during two visual tasks involving 9° and 18° convergence, in those participants with complete and reliable data.Convergence led to a thickening of the total anterior eye wall (5.9 ± 1.4 μm) and forward movement (10 ± 2 μm) of the nasal anterior scleral surface (both p 0.001). Larger changes were found at 18° than at 9° convergence and in more peripheral nasal scleral regions. There was a significant association between total wall thickening and forward movement of the scleral surface. Refractive group was not a significant main effect, but there were significant interactions between refractive group and the thickness changes with convergence in different scleral regions.During convergence, the biomechanical forces acting on the eye lead to nasal anterior scleral thickening and forward movement of the nasal scleral surface.

Purpose.In the paper, we describe and discuss the results of epidemiological studies concerning myopia carried out in Poland.Materials and Methods. Results from the examination of 5601 Polish school children and students (2688 boys and 2913 girls) aged 6 to 18 years were analyzed. The mean age was 11.9 ± 3.2 years. Every examined student had undergone the following examinations: distance visual acuity testing, cover test, anterior segment evaluation, and cycloplegic retinoscopy after instillation of 1% tropicamide, and a questionnaire was taken.Results. We have found that (1) intensive near work (writing, reading, and working on a computer) leads to a higher prevalence of myopia, (2) watching television does not influence the prevalence of myopia, and (3) being outdoors decreases the prevalence of myopia.Conclusions. The results of our study point to insufficiency of accommodation contributing to the pathogenesis of myopia.

We hypothesize that the typically narrower palpebral apertures of East Asian eyes in combination with the narrowing of this aperture during down-gaze combine to reduce light levels and image contrast in the inferior retina during near work, thus creating peripheral deprivation in these eyes that could generate deprivation myopia in children culturally encouraged to perform near work.We photographed the right eyes of 53 Chinese children during down-gaze (from 10 to 40 degrees) from the fixation point and the primary gaze position. From these images, we determined the size and shape of the effective foveal and superior field entrance pupil at different down-gaze angles. By using an eye model with typical levels of off-axis higher-order aberrations, we quantified the impact of eyelid and eyelash vignetting of the pupil on both retinal illuminance and image quality using Visual Strehl Ratio (VSOTF), and the non-visually weighted Strehl Ratio (SROTF).The effective aperture for the superior visual field is vignetted during down-gaze by lids and lashes, producing reductions in retinal illuminance of 30% and60% at 20 and 40 degrees, respectively. However, the aperture vignetting effect on peripheral image modulation is small, with neural and aberration changes dominating image quality in the superior field during down-gaze.Occlusion of the pupil by eyelid and eyelashes during down-gaze is unlikely to produce significant superior field deprivation in East Asian eyes.

The purpose of this study is to examine the potential relationship between tonic accommodation (TA), near work induced TA-adaptation and the steady state closed-loop accommodation response (AR). Forty-two graduate students participated in the study. Various aspects of their accommodation system were objectively measured using an open-field infrared auto-refractor (Grand Seiko WAM-5500). Tonic accommodation was assessed in a completely dark environment. The association between TA and closed-loop AR was assessed using linear regression correlations and t -test comparisons. Initial mean baseline TA was 1.84 diopter (D) (SD ± 1.29 D) with a wide distribution range (−0.43 D to 5.14 D). For monocular visual tasks, baseline TA was significantly correlated with the closed-loop AR. The slope of the best fit line indicated that closed-loop AR varied by approximately 0.3 D for every 1 D change in TA. This ratio was consistent across a variety of viewing distances and different near work tasks, including both static targets and continuous reading. Binocular reading conditions weakened the correlation between baseline TA and AR, although results remained statistically significant. The 10 min near reading task with a 3 D demand did not reveal significant near work induced TA-adaptation for either monocular or binocular conditions. Consistently, the TA-adaptation did not show any correlation with AR during reading. This study found a strong association between open-loop TA and closed-loop AR across a variety of viewing distances and different near work tasks. Difference between the correlations under monocular and binocular reading condition suggests a potential role for vergence compensation during binocular closed-loop AR.

To investigate the effects of no correction versus full correction on myopia progression in Chinese children over a period of 2 years. Myopia was defined as cycloplegic spherical equivalent (SE) of ≤ −0.50 D. Uncorrection was defined as no spectacles worn, and full correction was defined as when the value of SE subtracted from the dioptric power of the child’s current spectacles was less than 0.5 D. Ocular examinations included visual acuity, cycloplegic autorefraction, axial length and vertometer measurements. Questionnaires were completed by parents on behalf of the children. A total of 121 myopic children, with a median age of 12.7 years, were screened from the Anyang Childhood Eye Study, with 65 in the uncorrected group and 56 in the full correction group. At 2-year follow-up, children with no correction had slower myopia progression (−0.75 ± 0.49 D vs. −1.04 ± 0.49 D, P

Background Myopia is a common ocular disease. Increasing myopia prevalence rate is posing a threat to the health and economy of the developing countries. Review of literature revealed a strong association of myopia with learned people and the possible role of environmental, nutritional, hereditary and near work in the increased prevalence of myopia. Objective to determine the prevalence of myopia among MBBS students in a private medical college and to find out the possible risk factors associated with the disease. Materials and Methods cross sectional study was conducted among the medical students of a private medical college of central Kerala using a pretested, semi structured questionnaire which was distributed to those who gave consent. The visual acuity of the students who participated was also noted using the Snellens chart. Results Out of 100 students 42 were myopes of which 38 were known cases and 4 were found out during our study. 45.33% of the female and 32% of male had myopia. Conclusion Prevalence of Myopia was found to be high among the medical students in this study. Regular eye check up is mandatory in medical students.

The recent "boom of myopia," described predominantly for East Asia, is assumed to result from increasingly demanding education programs that include extensive near work (and perhaps also extensive use of computers) and little exposure to bright light as found outdoors. Already in 1892, Hermann Cohn stated that the prevalence of myopia is related to the educational level which is related to the economic status of a country. It is not much appreciated that the rates of myopia were already high among school children in central Europe in the middle of the 19th century, as described by Hermann Cohn. From extensive research in recent times, three major approaches have emerged to interfere with myopia progression in children: (1) promoting exposure to bright light and enforce outdoor activity, (2) adapting/improving optical corrections and visual behavior to generate inhibitory signals for eye growth in the retina, and (3) applying atropine eye drops at low doses. However, Hermann Cohn had already proposed that low luminances during school work promote myopia development and requested that lighting in the classrooms needs to be at least "10 meter candles" (equivalent to an illuminance of 10 lux). Different from today, he explained the link between low light and myopia by shorter reading distances that he observed at low luminances of the reading surface (<

································································································································································································································ Purpose: The study was aimed to suggest the most effective color of the tinted lenses by evaluating the effect of the prescription with tinted lenses on the visual quality of the elderly at the age of the sixty or more. Methods: The visual acuity of fifty subjects at the age of sixty or more (17 males, 33 females with the averaged age of 71.0±6.3) were corrected to have the visual acuity at a far distance of 0.5 or more using a trial lens frame, and non-tinted, brown-tinted, and gray-tinted lenses were randomly applied on the trial frame. The minimum legibility and minimum separability were measured at a far distance in the aspect of the visual acuity and calculated as LogMAR and then, the visual acuity was compared. The stereopsis and contrast sensitivity were also estimated at a near distance in the aspect of the visual function. The participants’ preference for tinted lenses and their subjective symptoms of the visual perception and the movement were further surveyed. Results: The best minimum legibility and minimum separability was shown when wearing non-tinted lenses, and brown-tinted and gray-tinted lenses were in the next. The stereopsis and the contrast sensitivity at a near distance and the visual perception was the best when wearing brown-tinted lenses. It was surveyed that the subjective discomfort was the biggest when wearing gray-tinted lenses, and brown-tinted lenses were the best in the aspect of the subjective preference. Conclusions: As the result of this study, it was revealed that the visual acuity and visual function could be improved by the use of tinted ophthalmic lenses however, its change of visual acuity and visual function was not completely correlated with the subjective satisfaction. Therefore, the appropriate color of ophthalmic lenses should be selected in accordance with the individual visual perception and the main vision lifestyle in the elderly generation. From the present study, the use of non- or brown-tinted lens and brown- or gray-tinted lens can be recommended for distance work and near work, respectively, in the elderly generation under the illumination of about 1,000 lux.

Real and virtual three-dimensional (3D) imaging has found useful applications across different areas of health sciences and with the current rapidly progressive development stage we can expect that the use of 3D imaging soon will be a part of a daily visual load for medical personnel. To better understand the possible impact of prolonged work with 3D content on eye accommodative response and pupil size we compared two 3D imaging techniques - volumetric display that is real voxel-based system and anaglyph technique that is virtual pixel-based system. We have investigated accommodative lag and pupil responses in 38 emmetropic young adult after prolonged visual task with volumetric 3D display (n = 19) and with anaglyph 3D technique (n = 19). All participants were asked to perform relative depth perception task organized in three sessions. Accommodative response and pupil size were measured simultaneously immediately after each 10 min long session by using eccentric photorefractor (binocularly with 50 Hz frequency). We found differences in an accommodative lag and pupil size between right and left eye for the group who performed visual task on anaglyph 3D. The mean difference of accommodative lag between the right and the left eye was 0.13 ± 0.05 D (F1,36 = 2.71, P = 0.10). Slight pupil size differences between the right and the left eye was observed (F1,36 = 4.70, P = 0.04). For volumetric 3D group we did not find significant differences of accommodative lag and pupil size between both eyes. A weak negative correlation was observed between the pupil size and the accommodative lag (Spearman correlation coefficient ρ = -0.20, P ρ = -0.21, P = 0.011; anaglyph 3D ρ = -0.19, P = 0.019). It appears that prolonged near work with anaglyph 3D might cause unequal post-task accommodative response between both eyes that could force the visual system to the possible accommodation-vergence conflict. This suggest that the real 3D imaging would be more suitable for health care applications compared to virtual 3D.

BackgroundVarious types of near work have been suggested to promote the incidence and progression of myopia, while outdoor activity appears to prevent or retard myopia. However, there is a lack of consensus on how to interpret these results and translate them into effective intervention strategies. This study examined the association between visual acuity and time allocated to various activities among school-going children.MethodsPopulation-based survey of 19,934 students in grade 4 and 5 from 252 randomly selected rural primary schools in Northwest China in September 2012. This survey measured visual acuity and collected self-reported data on time spent outdoors and time spent doing various types of near activities.ResultsProlonged (>60 minutes/day) computer usage (-0.025 LogMAR units, P = .011) and smartphone usage (-0.041 LogMAR units, P = .001) were significantly associated with greater refractive error, while television viewing and after-school study were not. For time spent outdoors, only time around midday was significantly associated with better uncorrected visual acuity. Compared to children who reported no midday time outdoors, those who spent time outdoors at midday for 31-60 minutes or more than 60 minutes had better uncorrected visual acuity by 0.016 LogMAR units (P = .014) and 0.016 units (P = .042), respectively.ConclusionsUse of smart phones and computers were associated with declines in children's vision, while television viewing was not. Statistically significant associations between outdoor time at midday and reduced myopia may support the hypothesis that light intensity plays a role in the protective effects of outdoor time.

Myopia is the most common ocular disorder causing visual impairment worldwide. It is a public health issue in many parts of the world. Compared with Caucasian or other ethnicities, its prevalence in Asians, especially Japanese, Koreans, and Chinese, is much higher. Environmental and genetic factors play important roles in myopia development. Myopia is a multifactorial disease. Time spent outdoors, amount of near work, and educational level influence myopia onset and progression. Recent advances in modern technology and molecular biology including linkage analyses, candidate gene analysis, genome-wide association studies (GWAS), whole-exome sequencing (WES), and next-generation sequencing (NGS) have led to mapping and identifying many myopia-associated gene loci and variants. Understanding the genetic basis may help in myopia prediction and prevention. This review is to summarize recent major findings in myopia genetics with a focus in Asian populations.

Purpose To determine the myopia prevalence in Hong Kong Chinese children and their parents. Methods It was a population-based cross-sectional study. A total of 4257 children aged 6-8 years, and 5880 parents were recruited in the Hong Kong Children Eye Study. Cycloplegic autorefraction was measured for children; and non-cycloplegic autorefraction for parents. Parental educational level, children's outdoor time, and near work were collected by validated questionnaires. Results In children aged 6-8 years, 25.0% were myopic, and among them, 12.7% for the 6-year-olds, 24.4% for the 7-year-olds and 36.1% for the 8-year-old. About 0.7% of children aged 8 years were high myopia. In all age groups, boys (their myopia rate: 13.9% at 6 years, 26.7% at 7 years, and 38.3% at 8 years) were more myopic than girls (11.3% at 6 years, 22.0% at 7 years, 33.4% at 8 years). Among parents, 72.2% were myopic (mother, 73.2%; father, 70.7%) and 13.5% high myopia (mother, 12.8%; father, 14.5%). It was observed that prevalence decreased with ages and increased with education level. Conclusion There is a strikingly high prevalence of myopia in Hong Kong children aged 6-8, much higher than that of other regions of China. Of note, the prevalence of children was similar to that in 15 years ago. Furthermore, the myopia prevalence of parents is high, and it had already increased in this cohort. Prevention of childhood myopia is important, likewise for visual complications from high myopia in adults.

Technologies are in daily use, also for educational reasons and getting knowledge. Reading from screens and from papers are different. People are in need to adapt but it is slow process. It can make some different problems that affect people life quality. There is a need for solution. We offer one of the possible solutions: E-material formatting application, what improve comfort of using e-material in learning and study process and decrease near work load by adapting on individual needs. It is based on developed recommendations for user-centric and adaptive educational e-material creation and formatting. Possible technical solutions have been found.

In the present era, the full computerization of a country is necessary for the progress. The present era can be defined as “Computer Age”. It has seems that the work at the computer is very intensive & most tiring therefore countries like Germany has included computer operational work in the list of the 40 most harmful trades for the health & restricted work at the computer should not exceed 50% of the working time. In the developing countries like India where the remuneration for the work is far from satisfactory & the young generation is aspiring for more material gains which necessitate them to work overtime or have part-time jobs in addition to their legitimate work. This situation adds up to the works with the computer which badly affects their health. Computer Vision Syndrome (CVS) is the complex of eye and vision problems related to near work which are experienced during or related to computer use. CVS is characterized by visual symptoms which result from interaction with a computer display or its environment. In most cases, symptoms occur because the visual demands of the task exceed the visual abilities of the individual to comfortably perform the task. In CVS following Signs & Symptoms occurs.they are Presence of excessive debris & mucous strands in the tear film., Reduced or absence of marginal tear strip.Lusterless ocular surface - xerosis.,Lid Dry & Rough touch. And Symptoms are Itching, Burning sensation, Blurred vision, Dryness of eyes, Redness of eyes, Pricking Pain. , Foreign body Sensation, Difficulty in opening & closing the lids.For the study, we have taken Triphala Ghrita Tarpan for 7 days in three consecutive months for 30 patients in treated group and in controlled group eye exercises given like palming, eye movements for 7days in three consecutive months for 30 patients.The results are very much satisfactory in the treated group as compared to the controlled group.The details will be given in detail in full research paper.

The purpose of this study was to investigate the relationships among working hours, near work time, and perceived stress. In total, data of 3,776 workers from the Korea National Health and Nutrition Examination Survey VI were examined. The workers' working hours per week, daily near work time, and complaints of perceived stress were analyzed in conjunction with other sociodemographic and occupation-related variables. Multivariate logistic analysis found that workers with 3 and ≥4 hours of near work were more likely to report high perceived stress than were the reference group who had

Acute acquired comitant esotropia secondary to smart-phone use is a newly described phenomenon. This case report describes a boy with acute acquired comitant esotropia due to prolonged smartphone use who had improvement in binocular function after cessation of near work for several weeks. [ J Pediatr Ophthalmol Strabismus . 2018;55:e42–e44.]

Background: Unlike the usual skeletal muscles, ciliary muscles responsible for focusing the crystalline eye lens and extraocular muscles responsible for convergence eye movements appear resistant t ...

The aim was to determine the characteristics of near work-induced transient myopia (NITM) in asymptomatic Indian subjects and the influence of target size and contrast.Two studies were conducted: First, 24 myopes and 24 emmetropes viewed four targets (N8 and N12 with 50 and 90 per cent contrasts) placed at 0.2 m for five minutes. The refractive status was assessed objectively, before and after carrying out the near task, with the Grand Seiko WAM-5500 open-field autorefractor under monocular viewing conditions. Second, a different group of 24 myopes and 24 emmetropes viewed a N12 target with 90 per cent contrast for 60 minutes with pre- and post-refractive state measurements repeated as above. NITM was defined as the difference between pre-task and post-task distance refraction.In the first study, myopes demonstrated an initial post-task myopic shift of 0.21 D, whereas emmetropes demonstrated a small hyperopic shift of 0.07 D (p 0.001). The myopes demonstrated a decay time constant of 6.07 seconds. There was no effect of target size or contrast on the magnitude of the NITM or the decay time constant (p 0.05). In the second study, myopes showed a NITM of 0.31 D, which was significantly greater than emmetropes (p 0.001). The myopes demonstrated a decay time constant of 8.16 seconds.The magnitude of the NITM was higher in myopes compared to emmetropes for both five minute and 60 minute viewing time. The NITM decayed slightly faster than that found in previous literature for some other ethnic groups. Potential reasons for these findings are discussed.

OBJECTIVE: When workers experience domestic violence (DV) at home, impacts are felt in the workplace; however, little research is available on this topic. METHODS: We conducted an online survey regarding the impacts of DV at work. RESULTS: A total of 8429 people completed the survey. More than a third of respondents reported experiencing DV; among them, more than a third reported that DV affected their ability to get to work, and more than half reported that it continued at or near work. Most reported that DV negatively affected their performance. Almost all respondents, regardless of DV experience, believed that it impacts victims' work lives. CONCLUSIONS: This research identifies the scope and impact of DV on workers and workplaces. The data should assist governments, unions, and employers to enact and evaluate proactive practices to address the impact of DV in the workplace. Language: en

Aim To investigate if trapezius muscle activity increases over time during visually demanding near work. Methods The vision task consisted of sustained focusing on a contrast-varying black and white Gabor grating. Sixty-six participants with a median age of 38 (range 19–47) fixated the grating from a distance of 65 cm (1.5 D) during four counterbalanced 7-min periods: binocularly through −3.5 D lenses, and monocularly through −3.5 D, 0 D and +3.5 D. Accommodation, heart rate variability and trapezius muscle activity were recorded in parallel. Results General estimating equation analyses showed that trapezius muscle activity increased significantly over time in all four lens conditions. A concurrent effect of accommodation response on trapezius muscle activity was observed with the minus lenses irrespective of whether incongruence between accommodation and convergence was present or not. Conclusions Trapezius muscle activity increased significantly over time during the near work task. The increase in muscle activity over time may be caused by an increased need of mental effort and visual attention to maintain performance during the visual tasks to counteract mental fatigue.

Purpose. To investigate the effects of atropine on choroidal thinning induced by hyperopic retinal defocus. Methods. Ten young adults with myopia (−1.00 D to −5.00 D) viewed a video at 6 metres for 60 minutes on successive days. On day 1, one eye (control) was distance corrected with a contact lens; the other (experimental) eye wore a contact lens imposing 2.00 D of hyperopic retinal defocus. Sub- and perifoveal choroidal thickness (SFCT, PFCT) were monitored with optical coherence tomography. On day 2, the procedure was repeated but the experimental eye had received one drop of 0.5% atropine 22 hours earlier. Results. On day 1, eyes exposed to hyperopic defocus developed progressively thinner choroids (SFCT (baseline) = 253 ± 32 μm versus SFCT (40 mins) = 244 ± 31 μm, p=0.004), whereas SFCT and PFCT in control eyes did not change (p>0.17). On day 2 (22 hours after instilling atropine), baseline SFCT and PFCT were not different to day 1 (p>0.05) and hyperopic defocus failed to thin the choroid (max change in SFCT = +2 ± 2 μm, p=0.36). Conclusions. Atropine abolished choroidal thinning induced by hyperopic defocus without changing baseline choroidal thickness. The results suggest that atropine inhibits signals associated with hyperopic defocus, for example, from lag of accommodation during near work. This trial is registered with ACTRN12617001519347.

The prevalence of myopia has increased worldwide in recent decades and now is endemic over the entire industrial world. This increase is mainly caused by changes in lifestyle and behavior. In particular, the amount of outdoor activities and near work would display an important role in the pathogenesis of the disease. Several strategies have been reported as effective. Spectacles and contact lenses have shown only slight results in the prevention of myopia and similarly ortokerathology should not be considered as a first-line strategy, given the high risk of infectious keratitis and the relatively low compliance for the patients. Thus, to date, atropine ophthalmic drops seem to be the most effective treatment for slowing the progression of myopia, although the exact mechanism of the effect of treatment is still uncertain. In particular, low-dose atropine (0.01%) was proven to be an effective and safe treatment in the long term due to the lowest rebound effect with negligible side effects.

Purpose. To investigate the prevalence and related factors for myopia in school-aged children in the Economic and Technological Development Zone of Qingdao, Eastern China. Methods. A total of 4890 (aged 10 to 15 years) students were initially enrolled in this study. 3753 (76.75%) students with completed refractive error and questionnaire data were analyzed. The children underwent a comprehensive eye examination. Multiple logistic regression models were applied to assess possible factors associated with myopia. Results. The prevalence of myopia increased as the children’s grade increased (χ2=560.584, P<0.001). Low myopia was the main form of myopia in adolescent students (30.22%). With the growth of age, students spent significantly more time on near work (P=0.03) and less time on outdoor activity (P<0.001). In multivariate models, only the following variables were significantly associated with myopia: age, two myopic parents, outdoor activity time, and continuous near work without 5 min rest. Conclusions. The prevalence of myopia increased as the grade increased. Age, two myopic parents, and continuous near work time without 5 min rest were risk factors for myopia. Outdoor activities had protective effect for myopia.

Worldwide, and especially in Asia, myopia is a major vision-threatening disorder. From AD 1600 on, to prevent myopia, authors warned against near work without sufficient pauses. There was an abundance of theories about the causes of myopia, the most common one being the necessity of extra convergence on nearby work with thickened extraocular muscles and elevated intraocular pressure. Ocular tenotomies against myopia were in vogue for a while. Axial lengthening of the eye in myopia was mentioned around 1700, but it took 150 years to become accepted as the most prevalent sign of high myopia. In 1864, a lucid concept of myopia and other ametropias arose through a clear separation between accommodation and refraction. Posterior staphyloma was known around 1800 and its association with myopia became evident some 30 years later. There still seems to be no generally accepted classification of myopia and particularly not of degenerative or pathologic myopia. This review focuses on myopia from 350 BC until the 21st century and on the earliest writings on the histology of eyes with posterior staphyloma. A proposal for myopia classification is given.

Post-task refraction shifts were evaluated with eccentric photorefraction technique to better understand response of visual system and eye accommodation to sustained near work with 3D image formed by volumetric display.

Objective: To evaluate the association between sleeping time and myopia in children. Methods: The data from 15316 Chinese schoolstudents aged 6 to 18 years from 19 randomizedschools in Beijing cityincludingthe cycloplegicrefractor and the possible genetic, environmental and behavioral habitrisk factors (parental myopia, parental education, reading or writing distance, hours of sports,hoursof watching TV or using computer, and hours of sleeping)were evaluated to explore the key risk factors for myopia. Univariate and multiplelogisticregression analysis were performed, and receiver operator characteristic (ROC) curves generated. Differences among the areas under ROC curves were compared using the method of multiple comparison with the best. Results: After controlling for age, gender, parental myopia, father’s education, reading or writing distance, hours of sports, hours of watching TV or using computer per day, hours of studying per day, myopia was associated with short sleeping time (lowest time span) versus long sleeping time (highest time span) (odds ratio=3.37; 95%CI 3.07-3.70). Controlling for the same factors, children with shorter sleeping time had significantly more myopic refractions (-1.69D for children with the shortest sleeping time compared with -1.29D for children with the longest sleeping time per day). Aanlysis of the areas under the ROC curves showed five variables with predictive values better than chance: age, sleeping time, reading or writing distance, hours of studying, and parent’s myopia. Conclusion: Sleeping time may be an independent risk factor of myopia, and this relationship may not be explained merely by increased hours of studying or hours of watching TV. An interesting observation is that sleeping time may be an important risk factor for myopia compared with other near work factors. The complexity of the relationship between sleeping time and myopia need additional studies to clarify any cause-effect relationship.

Highway workers frequently work in close proximity of live traffic in highway work zones, traffic accidents therefore have devastating effects on worker safety. In order to reduce the potential for such accidents, methods involving use of advisory signs and police presence have been used to mitigate accident risks and improve safety for highway workers. This research evaluates the magnitude of the speeding problem in highway work zones and the effects of four levels of police presence on improving work zone safety. Speed data were collected in six different work zone locations in northern and southern California and used to determine the magnitude and nature of speeding problem in highway work zones. In addition data were collected over 11 test-days in four work zones with four levels of police presence: radar speed display with police decal and lighting, passive use of a police vehicle with radar speed display, passive use of a police vehicle without radar speed display, and active police speed enforcement near work zones. This paper analyzes this data using statistical methods to evaluate the effectiveness of these different methods of speed control on the safety of the work zone. Four Measures of Effectiveness (MOE) were used in this evaluation consisting of average speed reduction, speed variance, 85th percentile speed, and proportion of high speed vehicles. The results indicate that all levels of police presence provided statistically significant improvements in one or more of the MOEs.

Myopia is the most common cause of refractive error in children. It is the most common ocular disorder worldwide. Apart from genetic factors, age and environmental factors have also been found to be closely associated as predictors of myopia. A comprehensive literature search was on online platforms using terms Myopia review, onset, progression, treatment, control, updates, bifocals, Atropine, and Orthokeratology. All the relevant articles published in English in last 10 years were analyzed and included. Excessive near work and prolonged screen usage have been proven as definite risk factors apart from genetics. Role of Vitamin D and outdoor activities are still having a controversial stand. Myopia treatment has come a long way from glasses/contact lenses to advanced minimally invasive refractive procedures such as femtosecond-assisted procedures and small incision lenticule extraction. With tremendous improvement in technology and increased dependence on digital devices, control of myopia progression remains a big challenge. Use of bifocals, progressive glasses, rigid contact lenses, and soft bifocals lenses have been studied widely. These all measures seem to do well in initial years, but long-standing results are not encouraging. The results with low-dose atropine have been convincing, but long-term follow-up results are still awaited.

Purpose: To investigate the changes occurring in the axial length, choroidal thickness and anterior biometrics of the eye during a 10 minute near task performed in downward gaze. Methods: Twenty young adult subjects (10 emmetropes and 10 myopes) participated in this study. To measure ocular biometrics in downward gaze, an optical biometer was inclined on a custom built, height and tilt adjustable table. Baseline measures were collected after each subject performed a distance primary gaze control task for 10 mins, to provide wash-out period for prior visual tasks before each of three different accommodation/gaze conditions. These other three conditions included a near task (2.5 D) in primary gaze, and a near (2.5 D) and a far (0 D) accommodative task in downward gaze (25°), all for 10 mins duration. Immediately after, and then 5 and 10 mins from the commencement of each trial, measurements of ocular biometrics (e.g. anterior biometrics, axial length, choroidal thickness and retinal thickness) were obtained. Results: Axial length increased with accommodation and was significantly greater for downward gaze with accommodation (mean change ± SD 23 ± 13 µm at 10 mins) compared to primary gaze with accommodation (mean change 8 ± 15 µm at 10 mins) (p < 0.05). A small amount of choroidal thinning was also found during accommodation that was statistically significant in downward gaze (13 ± 14 µm at 10 mins, p < 0.05). Accommodation in downward gaze also caused greater changes in anterior chamber depth and lens thickness compared to accommodation in primary gaze. Conclusion: Axial length, choroidal thickness and anterior eye biometrics change significantly during accommodation in downward gaze as a function of time. These changes appear to be due to the combined influence of biomechanical factors (i.e. extraocular muscle forces, ciliary muscle contraction) associated with near tasks in downward gaze.

Introduction: The American Ophthalmological Association defines CVS as that “complex of eye vision problems related to near work which are experienced during or related to computer use.” The most prevalent ophthalmologic symptoms associated are headache, dryness of eyes, watering, eye strain, redness, grittiness, blurring of vision which are often overlooked but are preventable at the same time. According to American Journal of Ophthalmology, 70-75% of computer workers have eye problems which are the most frequently related health problems. We have conducted this study to assess the asthenopic symptoms occurring in computer workers. Method: This study was done on 330 people working at Bhopal and symptoms related to CVS were studied during the pre and post interventional period of 3 months. Result: The intervention was able to decrease asthenopic complaints of computer workers to 46.5%. Conclusion: There was a significant decrease in the asthenopic symptoms following intervention but limited results were achieved due to inadequate infrastructure in work place, non-compliance of the subjects, limited time of intervention

Purpose To compare light intensity and near-visual tasks objectively between rural and urban children. Methods Clouclip, a wearable device, was applied to assess metrics of these two factors in 78 fifth-grade students from an urban and from a rural school. Results The light intensity experienced by urban students was found significantly lower both in the school period (614.05 ± 178.77 vs. 918.41 ± 257.81 lux, P < 0.001) and on the weekend (444.53 ± 216.65 vs. 882.21 ± 536.67 lux, P < 0.001). The duration of exposure to bright light (>1000 lux) was also substantially shorter for urban students. Although no significant difference was found in near work–related behaviors during the school period and the weekend, for the after-school period the urban students had a shorter average viewing distance (30.94 ± 4.14 vs. 34.81 ± 3.93 cm, P < 0.001), a longer accumulated duration of near work (2.25 ± 0.53 vs. 1.95 ± 0.46 hours, P = 0.010), a greater time ratio of near work (56% ± 14% vs. 49% ± 14%, P = 0.045), and a greater time ratio of excessively close near work (49% ± 13% vs. 40% ± 12%, P = 0.001). Conclusions Our data indicate there were substantial differences in light exposure and near-work metrics between the two regions. The correlation between these differences and the discrepancy in regional myopia prevalence needs further investigation. Translational Relevance The objective quantification of these metrics might help explain the varied myopia prevalence among regions.

Purpose :To evaluate the efficacy of two non-surgical interventions of vision improvement in children.Methods :A prospective, randomized, pilot study to compare fogging method and the use of head mounted 3D display. Subjects were children, between 5 to 15 years old, with normal best corrected visual acuity (BCVA) and up to -3D myopia. Subjects played a video game as near point work, and received one of the two methods of treatments. Measurements of uncorrected far visual acuity (UCVA), refraction with autorefractometer, and subjective accommodative amplitude were taken 3 times, at the baseline, after the near work, and after the treatment.Results :Both methods applied after near work, improved UCVA. Head mounted 3D display group showed significant improvement in UCVA and resulted in better UCVA than baseline. Fogging group showed improvement in subjective accommodative amplitude. While 3D display group did not show change in the refraction, fogging group’s myopic refraction showed significant increase indicating the eyes showed myopic change of eyes after near work and treatment.Discussion :Despite our lack of clear knowledge in the mechanisms, both methods improved UCVA after the treatments. The improvement in UCVA was not correlated to measured refraction values.Conclusion :UCVA after near work can be improved by repeating near and distant accommodation by fogging and 3D image viewing, although at the different degrees. Further investigation on mechanisms of improvements and their clinical significance are warranted.

We evaluate the impact of near work has on myopia and how they differ across generation. The study subjects were 201(83 males and 118 females) adults who live in Cheongju and Daejeon. Myopia was defined as more than or equal to (-)2.50D. The subjects were divided myopic and control group. The surveys and eye tests that are related to near work and refractive error were conducted and the relationship between the degree of myopia and near work was investigated. Then, the groups were divided into people in their 20s and 30s and the comparisons were made again. The survey results showed significant differences between myopic and control groups that depended on: hours spent in school and outdoor activities during high school period, degree of refractive error caused by level of exercises during the junior high school and high school years, refractive error based on the type of high schools, also hours spent in school and outdoor activities. When the same question was done on the group in their 20s and 30s, there was a different outcome in trends between the groups and refractive error depending on whether they exercised. The degree of near work is one of the environmental risk factors that affect myopia and must be considered when studying myopic progression. However, when discussing specific behavioral patterns in relations to myopia prevention, culture and visual environment of a given generation must also be considered.

To evaluate the 1-year progression of myopia and associated risk factors in second-grade primary school children.The myopia investigation study in Taipei provided semiannual visual acuity testing and cycloplegic refraction for all second-grade primary school children (mean age: 7.49 years) in Taipei who provided parental consent. A questionnaire was distributed to the participants' parents before the first and third examinations. We evaluated 1-year follow-up data for children noted to have myopia on the first examination. Multinomial logistic regression models were applied to assess risk factors associated with myopia progression. Myopia progression was categorised, based on the change in spherical equivalent (ΔSE) over 1 year, as slow (ΔSE-0.5 dioptres (D)), moderate (-1.0 DΔSE≤-0.5 D) or fast (ΔSE≤-1.0 D). Of the 4214 myopic children, data were analysed for 3256 (77.3%) who completed the 1-year follow-up evaluation.The baseline SE was -1.43±1.1 D. The average ΔSE was -0.42±0.85 D, with 46.96%, 28.50% and 24.54% of the study subjects showing slow, moderate and fast myopia progression, respectively. When compared with slow myopia progression, fast myopia progression was associated with a greater myopic SE at baseline (OR: 0.67, 95% CI: 0.61 to 0.72) and a shorter eye-object distance when doing near work (OR: 1.45, 95% CI: 1.18 to 1.78). More outdoor activity time and self-reported cycloplegic treatment were not associated with slow myopia progression.Children with fast annual myopia progression were more myopic at baseline and had a shorter reading distance. Our study results highlight the importance of having children keep a proper reading distance.

PURPOSE:To investigate the characteristics of various near work related behaviors among primary students and their associations with changes in myopia related ocular biometric parameters during one-year of follow up. METHODS:A school-based sample of 4,814 primary 1st to 4th grade students aged 6-10 years old were selected by cluster randomization based on probability proportion to size in 2013. At baseline, students together with their parents filled in a self-administered questionnaire on 9 aspects of near work related behaviors and some important covariants of myopia. A comprehensive set of eye examinations including axial length (AL) and cycloplegic refraction was conducted both at baseline and one year later. RESULTS:With the grade level increase, students did increasingly better at finding various ways to have an eye break, but they were increasingly likely to continuously do long-time near work without an eye break. Keeping a reasonable eye distance and correct hand posture for reading, writing, or watching TV became worse for the first time before grade 2, but then became better at grade 3. In contrast, selecting appropriate lighting environments or situations and keeping a balanced diet became better for the first time before grade 2, but then became worse at grade 3. At one-year follow up, the mean AL increased by 0.32 ± 0.35 mm, the ratio of AL divided by the mean corneal radius of curvature (AL/CR ratio) increased by 0.032 ± 0.054, the myopic spherical equivalent (SE) increased by -0.51 ± 0.51 diopters and the incidence of myopia was 16.0% (237/1,477). After controlling for the confounding effects of parental myopia, student's age, gender, height, daily near work time, daily outdoor activity time and all of the other near work related behaviors, keeping a reasonable distance when reading, writing and watching TV was associated with elongation of the AL [standard coefficient beta = -0.062, P = 0.004], a change in SE [beta = -0.072, P = 0.020] and incident myopia [adjusted odds ratio (aOR) = 0.90, 95% confidence interval (CI): 0.84-0.96]. Selecting an environment with adequate light for visual comfort to read and write was related to elongation of the AL [beta = -0.039, P = 0.034] and increase of AL/CR ratio [beta = -0.030, P = 0.048]. Also, not continuing to do near work for more than 30-40 minutes without an eye break was related to increase of the AL/CR ratio [beta = -0.028, P = 0.044] and a change in SE [beta = -0.064, P = 0.023]. CONCLUSION:Various near work related behaviors changed according to grade level in primary school students. Independent of hereditary factors, daily near work load and outdoor activity, near work related behaviors such as keeping an inappropriate eye distance for near work, selecting inadequate lighting environments, and continuing to do near work without an eye break were risk factors for myopic shifts.

Background Chinese traditional “eye exercises of acupoints” have been advocated as a compulsory measure to reduce visual symptoms, as well as to retard the development of refractive error, among Chinese students for decades. The exercises are comprised of a 5-min, bilateral eye acupoint self-massage. This study evaluated the possible effect of these eye exercises among Chinese rural students. Methods Eight hundred thirty-six students (437 males, 52.3 %), aged 10.6 ± 2.5 (range 6–17) years from the Handan Offspring Myopia Study (HOMS) who completed the eye exercises and vision questionnaire, the convergence insufficiency symptom survey (CISS) questionnaire, and had a cycloplegic refraction were included in this study. Results 121 (14.5 %) students (64 males, 52.9 %) performed the eye exercises of acupoints in school. The multiple odds ratio (OR) and 95 % confidence interval (CI) for those having a “serious attitude” towards performing the eye exercises (0.12, 0.03–0.49) demonstrated a protective effect for myopia, after adjusting for the children’s age, gender, average parental refractive error, and the time spent on near work and outdoor activity. The more frequently, and the more seriously, the students performed the eye exercises each week, the less likely was their chance of being myopic (OR, 95 % CI: 0.17, 0.03–0.99), after adjusting for the same confounders. However, neither the “seriousness of attitude” of performing the eye exercises (multiple β coefficients: -1.58, p = 0.23), nor other related aspects of these eye exercises, were found to be associated with the CISS score in this sample. Conclusions The traditional eye exercises of acupoints appeared to have a modest protective effect on myopia among these Chinese rural students aged 6–17 years. However, no association between the eye exercises and near vision symptoms was found. Electronic supplementary material The online version of this article (doi:10.1186/s12906-016-1289-4) contains supplementary material, which is available to authorized users.

In an experimental study two levels of oculomotor load were induced via optical trial lenses. Trapezius muscle activity was measured with bipolar surface electromyography and normalized to a submaximal contraction. Sixty-six subjects with a median age of 36 (range 19-47, std 8) viewed a black and white Gabor grating (5 c/deg) for two 7-min periods monocularly through a 0 D lens or binocularly through -3.5 D lenses. The effect of time was separately regressed to EMG in two different subgroups of responders: a High-Oculomotor-Load (HOL) and a Low-Oculomotor-Load (LOL) group. A linear regression model was fitted on group level with exposure time on the x-axis and normalized trapezius muscle EMG (%RVE) on the y-axis. The slope coefficient was significantly positive in the -D blur condition for only the HOL subgroup of responders: 0.926 + Time(min 1-7) × 0.088 (p = 0.002, r(2)=0.865). There was no obvious sign of this activity to level off or to stabilize. These results suggest that professional information technology users that are exposed to a high level of oculomotor load, during extended times, are at an increased risk of exhibiting an increased trap.m. activity.

Nowadays, ophthalmologists are facing a new group of patients having eye problems related to prolonged and excessive computer use. When the demand for near work exceeds the normal ability of the eye to perform the job comfortably, one develops discomfort and prolonged exposure, which leads to a cascade of reactions that can be put together as computer vision syndrome (CVS). In India, the computer-using population is more than 40 million, and 80% have discomfort due to CVS. Eye strain, headache, blurring of vision and dryness are the most common symptoms. Workstation modification, voluntary blinking, adjustment of the brightness of screen and breaks in between can reduce CVS.

Myopia is becoming a global public health problem in our society. The global progression of myopia might develop due to near work activities (reading, writing, homework, computer) and less outdoor activities. Recent studies show that beside genetic component, geography and ethnicitiy do have also an impact in the development and progression of myopia.Bangladesh Journal of Medical Science Vol.16(3) 2017 p.337-338

The current theories relating to the development and progression of myopia are related to exposure of the eye to hyperopic defocus. This paper discusses these theories and the large body of recent research investigating the evidence behind them. As both human and animal studies demonstrate, when considering the potential influence of defocus on eye growth, the duration of exposure as well as the type and magnitude of the blur are important. In addition, we must understand the defocus threshold over which an eye growth signal can be made. Investigations with respect to central defocus alone have been unable to find a unified theory due to (1) insufficient evidence showing refractive group differences in the amount of central defocus actually present and (2) unsuccessful attempts to wholely reduce myopia progression using corrective lenses. Recent research measuring peripheral blur is summarised in this paper and modelled together with previous measurements of peripheral defocus thresholds, providing an up-to-date perspective on myopia.

Background/aims To investigate the influence of a period of sustained near work upon axial length in groups of emmetropes (EMM) and myopes. Methods Forty young adult subjects (20 myopes and 20 emmetropes) were recruited for the study. Myopes were further classified as early onset (EOM), late onset (LOM), stable (SM) or progressing (PM) subgroups. Axial length was measured with the IOLMaster instrument before, immediately after and then again 10 min after a continuous 30 min near task of 5 D accommodation demand. Measures of distance objective refraction were also collected. Results Significant changes in axial length were observed immediately following the near task. EOM axial length elongated on average by 0.027±0.021 mm, LOM by 0.014±0.020 mm, EMM by 0.010±0.015 mm, PM by 0.031±0.022 mm and SM by 0.014±0.018 mm. At the conclusion of the 10 min regression period, axial length measures were not significantly different from baseline values. Conclusion Axial elongation was observed following a prolonged near task. Both EOM and PM groups showed increases in axial length that were significantly greater than emmetropes.

Twenty years of investigation into emmetropization and the development of myopia has led to several recent insights. Accommodation appears to be an important visual signal for emmetropization. Lens thinning during emmetropization and its cessation at the onset of myopia suggest that interruption of lens stretch during growth is an important part of the process of developing myopia. The ciliary muscle may play a greater role in emmetropization and myopia than previously thought. Time spent outdoors, not near work, may be the more important environmental variable in myopia. The effect of time outdoors shows an important interaction with a substantial genetic contribution to the risk of myopia.