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Childrens' vision-testing device could catch problems

According to figures reported by the University of Tennessee, even though 85 percent of a child’s learning is vision-related, about 80 percent of American children have never had their eyes tested before starting kindergarten.

Even when tests are performed, they are usually only capable of detecting no more than a couple of conditions.

Unfortunately, this means that vision-related learning disabilities such as dyslexia can be missed, and may not be noticed until they are well established.

Now, however, researchers at U Tennessee’s Space Institute have developed a new type of vision-testing system for young children, that could catch a variety of vision problems while they’re still reversible.

The device, known as the Dynamic Ocular Evaluation System (DOES), is reportedly inexpensive, kid-friendly, and only takes about a minute to learn how to use.

It was invented by Ying-Ling Ann Chen, a research assistant professor in physics. She was assisted by Lei Shi, a post-doctoral research associate in laser application, and Jim Lewis, a professor emeritus in physics.

"Vision screening is important at an early age to detect several different causes of vision disorders," said Chen.

"The few children that do get screened today aren't being screened adequately. For instance, many current screening methods do one eye at a time and studies show young eyes will accommodate significantly, and this causes inaccurate results."

Children using DOES simply sit and watch a three-minute cartoon, or play a computer game. No scary eye dilation is necessary, nor are any verbal responses from the child - this point is particularly important, as children taking eye tests are sometimes simply too young to know what their vision should be like, so what they tell clinicians can be misleading.

As the cartoon begins, a three-second procedure uses infra-red light to assess the child's ocular alignment, and checks for binocular refractive risks, high-order aberrations, ocular scattering, and significant neural problems.

This is followed by dynamic tests for less significant signs of abnormal ocular alignment, neural responses, and amblyopia (lazy eye).


The researchers plan on adding more tests, that would use the child's vision to check for mental problems including attention deficit hyperactivity disorder, post-traumatic stress disorder, autism, and dyslexia.

All of the data and images are digitally recorded, and can be sent electronically to specialists if needed.

Chen and her U Tennessee colleagues hope that DOES could someday become a standard piece of equipment in pediatrician's offices.

"By not testing our youth, we are potentially missing the window for effective treatment for a lot of conditions," she stated.

Playing Outdoors Helps Children see further

A new analysis of recent eye health studies shows that more time spent outdoors is related to reduced rates of nearsightedness, also known as myopia, in children and adolescents.

Myopia is much more common today in the United States and many other countries than it was in the 1970s. In parts of Asia, more than 80 percent of the population is nearsighted.

The analysis suggests that more exposure to natural light and/or time spent looking at distant objects may be key factors.

The analysis was led by Dr. Justin Sherwin of the University of Cambridge.

The data included in the analysis was drawn from eight carefully selected studies on outdoor time and myopia in children and adolescents, representing 10,400 participants in total.

Dr. Sherwin’s team concluded that for each additional hour spent outdoors per week, the chance of myopia dropped by approximately two percent.

Nearsighted children spent on average 3.7 fewer hours per week outdoors than those who either had normal vision or were farsighted.

Though the reasons aren’t yet clear, the protective effect appears to result from simply being outdoors rather than performing a specific activity.

Two of the eight studies examined whether children who spent more time outdoors were also those who spent less time performing near work, such as playing computer games or studying, but no such relationship was found in either study.

The amount of time spent on near work is of interest to researchers as another potential cause for the recent uptick in nearsightedness.

“Increasing children’s outdoor time could be a simple and cost-effective measure with important benefits for their vision and general health” said Dr. Khawaja.

“If we want to make clear recommendations, however, we’ll need more precise data. Future, prospective studies will help us understand which factors, such as increased use of distance vision, reduced use of near vision, natural ultra violet light exposure or physical activity, are most important.”

Video Games: A Cure for Lazy Eye - Amblyopia

At the American Academy of Opthalmology's annual meeting in Orlando, Florida, a team led by Somen Ghosh of the Micro Surgical Eye Clinic in Kolkata, India, reported that video game therapy improved the visual acuity of 10- to 18-year-olds with amblyopia, or "lazy eye".

This comes hot on the heels of similar findings from a study of adults with the condition, published in PLoS Biology by a team led by Roger Li and Dennis Levi of the University of California, Berkeley.

Even more impressive results may be on the horizon, as video games are combined with another approach, known as "perceptual learning".

Amblyopia occurs when the neural connections from one eye to the brain fail to develop normally. Over time, the brain reacts by ignoring the blurry input from this "weaker" eye.

The condition can be treated in childhood by patching the good eye and using visual training exercises to build the faulty neural connections - but the dogma has until recently been that little can be done after about the age of nine.

The idea of using video games stemmed from the discovery that expert gamers have unusually strong visual skills.

Subsequent studies have shown that action games can improve contrast sensitivity in people with normal vision.

Ghosh's studies involved children and teenagers with amblyopia who received the standard treatment of patch, eyeglasses and visual exercises, with or without supplementary treatments.

Even the group given just the basic treatment showed some improvement after one year - but those who were also instructed to play first-person shooter or driving games each day did noticeably better.



In adults, some of the best results in treating amblyopia have not used computer games, but instead trained people to distinguish blurry grey patterns known as Gabor patches.

In 2004, a team led by Uri Polat of Tel Aviv University showed that this perceptual learning resulted in two-fold improvements to sufferers' contrast sensitivity.

But even Polat, who has recently applied a similar approach to treating the natural deterioration in close vision that happens with age, concedes that the exercises are a bit boring for teens.

So what about combining perceptual learning with gaming? That's now being tried by Levi's lab, in collaboration with a team led by Daphne Bavelier of the University of Rochester in New York.

The researchers have embedded Gabor patches into a modified version of the first-person shooter Unreal Tournament, which they are now testing as a treatment for amblyopia.

"You have to shoot at the patches," Bavelier explains. "If you don't they transform into nasty bots that are really difficult to kill.

New reactive eye test may detect learning disabilities, early Alzheimer's

New reactive eye test may detect learning disabilities, early Alzheimer's

Two-year-old Jakeson Bowlby has a bull's eye sticker on his forehead that helps a computer system track the movement of his eyes.

He sits in a high chair and watches a video, but instead of Toy Story or another favourite, researchers at Queen's University show him a high-definition video that is part of a new test to assess brain function in toddlers. It jumps quickly from one image to another -- kangaroos sitting under a tree, kids playing soccer, buses and cars zooming by.

How quickly children can zero in on the kangaroos and follow the ball or the vehicles is a measure of how well their brains are directing the movement of their eyes, says Queen's neuroscientist Doug Munoz. He has devoted nearly two decades to documenting how eye control is related to abnormal brain function, both in children and adults.

His work is part of a broad investigation involving labs around the world which, over the last two decades, has laid the groundwork for relatively simple tests that could soon be used to detect everything from learning disabilities to the early onset of Parkinson's or Alzheimer's disease.

Munoz's latest project is aimed at the high chair set, a way to screen youngsters for problems that may make it difficult for them to learn in school. He and his colleague, Laurent Itti at the University of Southern California, have preliminary evidence that shows their "free viewing" test can identify children with attention deficit hyperactivity disorder and fetal alcohol spectrum disorder.