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Concussion in Kids: Less-Recognized Visual Changes

Here, Christina Master, MD, a pediatric sports medicine specialist at the Children’s Hospital of Philadelphia (CHOP) talks about vision issues following concussion in children.

«In our clinical and research practice here at CHOP, we have found that a number of children have visual issues after a concussion, but they’re not typically visual acuity issues. This is something we’d like to get the message out about.

The kids we see in our offices who have had a concussion often also have oculomotor issues (eye movements), whether they are related to problems with smooth pursuits (following an object), saccadic function (going from one object to another), or the vestibulo-ocular reflex function (vision and balance).

We find that they are often very sensitive to motion and vestibular stimuli, especially from busy and active environments. We also find that they have issues in school in regard to looking back and forth between a notebook, smartboard, monitor, or tablet. We’d like you to keep an eye out for these oculomotor issues. Many of them also seem to be related to binocular visual function (how the eyes function together); in particular, we notice that a convergence insufficiency can be a problem. These kids have problems focusing on objects that are far, and then transitioning from far to near and near to far again.

Photo from: https://www.todaysparent.com/kids/kids-health/concussions-hockey-problem/

As you can imagine, much of schoolwork is very visually oriented, and these issues can present problems. What we would encourage everyone to remember when assessing a child who has had a concussion is not only to look at visual acuity but also to assess oculomotor function, including smooth pursuits, saccades, and convergence. In treating these kids as they gradually return to school, it is also often helpful to recommend accommodations to allow them to have extra time, printed notes, larger-font printed materials, and, in general, extra support from a visual standpoint while their functions recover over time.

Please remember these issues when you’re evaluating kids in your office with concussion. Remember that these issues are not just about visual acuity but also include oculomotor and binocular visual issues like convergence insufficiency.»

From: http://www.medscape.com/viewarticle/876689

 

Eye Test Screens for Traumatic Brain Injury, Concussion

 

 

Photo from: https://www.washingtonparent.com/articles/1503/1503-concussions-in-kids-dr-bills-advice-for-worried-parents.php

Of the more than 340,000 cases of traumatic brain injury clinically confirmed from 2000 to 2015, mild injury accounted for 82.5%, according to US Department of Defense statistics.

However, traumatic brain injury is often only identified when moderate or severe head injuries have occurred, leaving mild cases undiagnosed, Dr Capó-Aponte and his colleagues explain in their scientific poster.

“Since approximately 30 areas of the brain and seven of the 12 cranial nerves deal with vision, it is not unexpected that the patient with traumatic brain injury may manifest a host of visual problems, such as pupillary deficit, visual processing delays, and impaired oculomotor tracking and related oculomotor-based reading dysfunctions,” Dr Capó-Aponte pointed out.
To see whether they could identify reliable biomarkers of mild traumatic brain injury that could be detected with an easily reproducible screening test, he and his colleagues looked for subtle visual changes that could be measured in the office or in the field.

From: http://www.medscape.com/viewarticle/865691

Vision and the Brain

The visual system includes 25 neocortical areas that are predominantly or exclusively visual in function, plus an additional 7 areas that are regarded as visual-association areas on the basis of their extensive visual inputs. A total of 305 connections among these 32 visual and visual-association areas have been reported. This represents 31% of the possible number of pathways if each area were connected with all others. The actual degree of connectivity is likely to be closer to 40%. The great majority of pathways involve reciprocal connections (in both directions) between areas.

From : https://www.ncbi.nlm.nih.gov/pubmed/1822724

 

Since approximately 60% of the nerve pathways are related to the processing of visual information, it is not surprising that severe visual problems occur in one or more concussions.

 

10 things you need to know about concussions

1. A concussion is a brain injury that can cause a variety of easy-to-miss symptoms. Doctors can’t “see” concussions using imaging. You don’t need to lose consciousness and a well-fitting helmet will not necessarily prevent one.

2. Symptoms can include headache, nausea, vomiting, light sensitivity, dizziness, confusion, slurred speech, poor balance, irritability, memory problems, blurred vision, sleepiness, sadness, anxiety or feeling in a fog. If you suspect a concussion, call the doctor.

3. If his head hurts, he’s off the ice, no questions asked. It doesn’t matter if he’s in the third period of a tied championship game.

4. Do not give Advil or Aspirin. Administered in large amounts, Advil and Aspirin can cause further bruising or internal bleeding. Tylenol is a safer bet; ask your doctor about proper dosages.

5. For the first 48 hours, be vigilant for signs of deterioration. Severe headache or persistent vomiting means you should go to the ER.

6. Concussion risk increases with each one. The brain is more likely to get reinjured if it hasn’t properly healed the first time. A child’s brain needs both physical and mental rest to heal (no jumping, no math problems).

7. Screens exacerbate a concussion headache. That means you have to limit the three things kids are most addicted to: TV, computer and phone.

8. If he says his head hurts, and the pain won’t go away, believe him—even if, ordinarily, your kid will do anything to skip school. The boredom of staying home and off screens will drive him—and you—so batty, there’s no way he’s faking.

9. His brain needs to rest in a dim room. This means no screens, pulling the curtains and keeping sunglasses handy. Contact teachers about making up homework in stages and catching up gradually.

10. Don’t send him back to school or sports until he’s symptom-free. Even with a mild concussion, this means no school or sports for at least a week—sometimes two.

From: https://www.todaysparent.com/kids/kids-health/concussions-hockey-problem/

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Does handwriting matter?

Not very much, according to many educators. The Common Core standards, which have been adopted in most states, call for teaching legible writing, but only in kindergarten and first grade. After that, the emphasis quickly shifts to proficiency on the keyboard.

But neuroscientists say it is far too soon to declare handwriting a relic of the past. New evidence suggests that the links between handwriting and broader educational development run deep.

Children not only learn to read more quickly when they first learn to write by hand, but they also remain better able to generate ideas and retain information. In other words, it’s not just what we write that matters — but how.

“When we write, a unique neural circuit is automatically activated,” said Stanislas Dehaene, from the Collège de France in Paris. “There is a core recognition of the gesture in the written word, a sort of recognition by mental simulation in your brain.

“And it seems that this circuit is contributing in unique ways we didn’t realize,” he continued. “Learning is made easier.”

A 2012 study led by Karin James, from Indiana University, lent support to that view. Children who had not yet learned to read and write were presented with a letter or a shape on an index card and asked to reproduce it in one of three ways: trace the image on a page with a dotted outline, draw it on a blank white sheet, or type it on a computer. They were then placed in a brain scanner and shown the image again.

The researchers found that the initial duplication process mattered a great deal. When children had drawn a letter freehand, they exhibited increased activity in three areas of the brain that are activated in adults when they read and write: the left fusiform gyrus, the inferior frontal gyrus and the posterior parietal cortex.

By contrast, children who typed or traced the letter or shape showed no such effect. The activation was significantly weaker.

Dr. James attributes the differences to the messiness inherent in free-form handwriting: not only must we first plan and execute the action in a way that is not required when we have a traceable outline, but we are also likely to produce a result that is highly variable.

In another study, Dr. James is comparing children who physically form letters with those who only watch others doing it. Her observations suggest that it is only the actual effort that engages the brain’s motor pathways and delivers the learning benefits of handwriting.

The effect goes well beyond letter recognition. In a study that followed children in grades two through five, Virginia Berninger, a psychologist at the University of Washington, demonstrated that printing, cursive writing, and typing on a keyboard are all associated with distinct and separate brain patterns — and each results in a distinct end product. When the children composed text by hand, they not only consistently produced more words more quickly than they did on a keyboard, but expressed more ideas. And brain imaging in the oldest subjects suggested that the connection between writing and idea generation went even further. When these children were asked to come up with ideas for a composition, the ones with better handwriting exhibited greater neural activation in areas associated with working memory — and increased overall activation in the reading and writing networks.

Samples of handwriting by young children. Dr. James found that when children drew a letter freehand, they exhibited increased activity in three significant areas of the brain, which didn’t happen when they traced or typed the letter. Credit Karin James

It now appears that there may even be a difference between printing and cursive writing — a distinction of particular importance as the teaching of cursive disappears in curriculum after curriculum. In dysgraphia, a condition where the ability to write is impaired, usually after brain injury, the deficit can take on a curious form: In some people, cursive writing remains relatively unimpaired, while in others, printing does.

Dr. Berninger goes so far as to suggest that cursive writing may train self-control ability in a way that other modes of writing do not, and some researchers argue that it may even be a path to treating dyslexia. A 2012 review suggests that cursive may be particularly effective for individuals with developmental dysgraphia — motor-control difficulties in forming letters — and that it may aid in preventing the reversal and inversion of letters.

Two psychologists, Pam A. Mueller of Princeton and Daniel M. Oppenheimer of the University of California, Los Angeles, have reported that in both laboratory settings and real-world classrooms, students learn better when they take notes by hand than when they type on a keyboard. Contrary to earlier studies attributing the difference to the distracting effects of computers, the new research suggests that writing by hand allows the student to process a lecture’s contents and reframe it — a process of reflection and manipulation that can lead to better understanding and memory encoding.

Reflection: Instead of giving a computer for continuous use to children with academic difficulties, such as dysgraphia, the child may have to be trained to write as well as he can (while using his computer) instead of giving up! Motor training can only help the child to write better. But as today, things that do not require any effort seem to take precedence. So, it is up to you, parents, to lead this battle!

From:
Karin H. James KH, Engelhardt L. The effects of handwriting experience on functional brain development in pre-literate children. Trends in Neuroscience and Education. Volume 1, Issue 1, December 2012, Pages 32–42

British study examines mobile phone effects on children

Photo JPL-blogueBritish scientists launched a major government-commissioned study on Tuesday into the effects of mobile phone usage on the developing brains of children.

About 2,500 children from London will be tested at the age of 11 and 12 and then again two years later, to assess how their cognitive abilities develop in relation to their changing use of phones and other wireless technologies.

blogue - fillette-iPhone

 Source : http://cypressinternalmedicine.com/wp-content/uploads/2011/11/photo-1.jpg

Professor Patrick Haggard, deputy director of the Institute of Cognitive Neuroscience at University College London, said it was the “largest follow-up study of its kind in adolescents worldwide”.

The World Health Organisation says there is no convincing evidence that mobile phones affect health, but existing data only goes back about 15 years.

In the study, the children will undertake classroom-based computerised tasks to measure cognitive abilities such as memory and attention.

“Cognition is essentially how we think, how we make decisions and how we process and recall information,” said Dr Mireille Toledano of Imperial College London, the principal investigator on the study.

Participants and their parents will also be asked questions about how they use mobile phones and other devices, and other aspects of their lifestyle.

An estimated 70 percent of all 11- to 12-year-olds in Britain now own a mobile phone, rising to 90 percent by the age of 14, according to the researchers.

The Study of Cognition, Adolescents and Mobile Phones (SCAMP) is being carried out by Imperial College London at the commission of the British Department of Health.

Letters were sent out to 160 different schools inviting them to enrol pupils, and tests will begin at the start of the new school year in September.

Imperial College is already involved in a separate international study, called Cosmos, into the possible long-term health effects of mobile phones on 290,000 adults in five European countries.

Video Displays and Dry Eye in Children

Photo JPL-blogueSource: http://www.practiceupdate.com/journalscan/9378

In a population of Korean children in grades 5 and 6 (ages 9–11), the authors compared symptoms and use of video display terminals in those with dry eye disease (9.7%, as determined by ophthalmic exam) with children without clinically determined dry eye. The risk factors for dry eyes in this population were related more to smartphone use (including mean duration of use, as reported by questionnaire) than to either computer or television viewing.

Blogue - Apple Addict

Photograph from Thomas PLESSIS (T.P Photographie)
                               With permission
                     http://www.thomas-plessis.com

 

The authors remind to keep the possibility of dry eye, which seems to be related to increased smartphone use, in mind in this population.

It is not uncommon for children between the ages of 9 and 11 — the population studied here — to exhibit potential signs of dry eye, which might include frequent blinking. Parents of children in this age range might also notice frequent or deep blinking behaviors that can be associated with tics or spasmodic blinking due to stress or anxiety.

The authors provide evidence that some of the signs and symptoms of ocular or visual discomfort can be associated with dry eyes. However, the jury is out on correlation or causation because the rate of dry eye signs was significantly greater in children with more smartphone use. The authors note that other visual factors have been reported as potentially associated with sustained smartphone use, such as accommodative issues and transient myopia. Because dry eye disease is not widely recognized as a potential problem in this age range, it adds to considerations in differential diagnosis of visual and ocular problems in childhood.

Two-hundred eighty-eight children were classified in either a dry eye disease group or control group according to the diagnostic criteria of dry eye disease. The results of ocular examinations, including best-corrected visual acuity, slit-lamp examination, and tear break-up time, were compared between groups. The results of questionnaires concerning video display terminal use and ocular symptoms were also compared.

Twenty-eight children were included in the dry eye disease group and 260 children were included in the control group. Gender and best-corrected visual acuity were not significantly different between the two groups. Smartphone use was more common in the dry eye disease group (71%) than the control group (50%) (P = .036). The daily duration of smartphone use and total daily duration of video display terminal use were associated with increased risk of dry eye disease (P = .027 and .001, respectively), but the daily duration of computer and television use did not increase the risk of dry eye disease (P = .677 and .052, respectively).

The results showed that smartphone use is an important dry eye disease risk factor in children. Close observation and caution regarding video display terminal use, especially smartphones, are needed for children.

Study source: JH Moon, MY  Lee, NJ Moon. Association Between Video Display Terminal Use and Dry Eye Disease in School Children. J Pediatr Ophthalmol Strabismus 2014 Mar 01;51(2)87-92.

Researchers recommend increasing time spent outdoors during school

Photo JPL-blogueDecidedly, studies on myopia and vitamin D or activities spent outside keep coming!

Results of a study involving 2,000 first-grade students prompted the researchers to suggest mandatory targets for the amount of time children spend outside during school hours.

Ian G. Morgan, PhD, of the Research School of Biology, Australian National University, Canberra, and the Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China, reported results of the Guangzhou Outdoor Activity Longitudinal Study here at the Association for Research in Vision and Ophthalmology meeting.

“The prevalence of myopia in East Asia has increased dramatically in the last 50 years, and a slower increase has been seen in Europe and North America,” Morgan said in his presentation.

The prevalence of high myopia, considered to be at least -6 D, is 20% in East Asia, he said, and prevention becomes essential.

The researchers recruited more than 2,000 first-grade students in 12 primary schools in Guangzhou. The school had been involved in previous studies, so records on visual acuity assessment dating back 20 years were available for children from this school, Morgan said.

One 45-minute class of outdoor activity was added at the end of the day, and children in the control group went home at the normal time, he said. The two groups of children were matched for prevalence of myopia, mean spherical equivalent and axial length.

Over the 3-year period, cumulative incident myopia was 39.5% in the control group and 30.4% in the intervention arm, a reduction of 23%, according to the study abstract.

“Differences in axial length did not quite reach statistical significance,” Morgan said. “It seemed to indicate that by increasing the amount of time outdoors, we were able to lower the level of incident myopia and prevalence of myopia. This is apparently a dose-response relationship.”

“We, therefore, recommend that myopia control programs based on increased time outdoors be developed in primary schools, at least in countries with currently high prevalence rates for myopia, with evidence-based mandatory targets for the amount of time children spend outdoors,” the authors concluded in their abstract.

 ?

Morgan asked: “Is the mechanism brighter light and increased dopamine release outdoors, or is it increased UV exposure outdoors? Evidence from animal studies favor the light-dopamine hypothesis, but a clinical trial of vitamin D needs to be done.”

From:

http://www.healio.com/optometry/optics/news/online/%7B5f21032e-c14c-4e33-96c2-345d7beaa63a%7D/researchers-recommend-increasing-time-spent-outdoors-during-school

New study finds vitamin D may be related to myopia in adolescents

Photo JPL-blogueRecently, researchers in South Korea have found that vitamin D levels may relate to severity of myopia.

Previous research has found that spending more time outdoors may help protect against developing myopia. This has led some researchers to speculate that vitamin D may play a role in myopia, as outdoor sun exposure is the main way for humans to produce vitamin D.

In the present study, researchers at the Catholic University of Korea in Seoul, South Korea looked at data from a national sample to determine if vitamin D relates to myopia. They used data from the Korea National Health and Nutrition Examination Survey (KNHANES). KNHANES is an ongoing population-wide survey that collects data on health and nutritional status of people in South Korea.

The researchers looked at data from 2,038 people aged 13 to 18 years old who had participated in KNHANES. The researchers examined their vitamin D levels, and noted whether they had myopia, and how severe their myopia was.

They wanted to know if vitamin D levels were related to the prevalence and severity of the condition. Of the 2,038 participants, 80.1% had myopia and 8.9% had very severe myopia. The researchers found that vitamin D levels were related to severity of myopia. This means lower vitamin D levels were related to more severe myopia among the participants.

“We found a significant association between low serum [vitamin D] concentration and myopia in Korean adolescents aged 13 to 18 years,” the researchers stated.

The researchers called for efforts to raise vitamin D levels among children through supplementation and outdoor activity in order to prevent the development of myopia.

To be followed…

Source:  http://www.vitamindcouncil.org/

Myopia: a world tour

Photo JPL-blogueThe eye’s shape depends on growth that occurs primarily during infancy, and to a lesser extent through adolescence. We think that growth is ruled in part by genetic instructions that humans have evolved over many millennia; if the genetic blueprint is defective, eyesight can certainly suffer. But growth of the eye also depends heavily on external cues — what scientists call visual feedback. The bombardment of light, with its colors and contrasts, and use of the eyes (reading, computer work, etc.) help guide proper or improper eye growth.

Scientists are now convinced that something about the visual environment and the use of the eys in this environment has changed drastically in recent decades, and those changes are driving the onslaught of nearsightedness seen in teens and young adults. From the early 1970s to the turn of the century, myopia prevalence in the United States rose from 25 percent to nearly 42 percent among people ages 12 to 54, a substantial shift in just one generation. The rate among U.S. young adults is 38 percent, up from 28 percent in the 1970s. On the other side of the globe, myopia rates in Singapore, which has gone from a sleepy port city to a center for international commerce, have risen from 43 percent among military conscripts (all young men) in the late 1980s to more than 80 percent today.

Myopia

Meanwhile, older generations haven’t experienced a sharp rise in the disorder. The rate in people over age 40 inChina and the United States is at about one-fourth.

Rural vs urban life

Studies suggest that rates of nearsightedness differ in ethnically related populations living in rural versus urban areas (data from country to country may not be comparable). City living appears to have a detrimental effect on visual problems (I. Morgan and K. Rose/Progress in Retinal and Eye Research 2005).

Because such increases also have not shown up in rural areas, scientists think the trend reflects new behaviors among young urbanites. With more people moving to cities, the trend is likely to worsen. For some, nearsightedness will be a mere inconvenience. But others, who develop high-degree myopia, will have worsening vision over time and a greater risk of cataracts, glaucoma or a detached retina later in life. Of those young men in Seoul and students in Shanghai who are nearsighted, roughly one in five already has high-degree myopia.

Vie rurale et urbaine

This graph shows the prevalence of myopia in China, Vietnam, India and Nepal whether people live in a rural or urban area. We see that the people who live in rural areas (with a school system probably more demanding) have a higher prevalence.

“There will be an epidemic of pathological myopia and associated blindness in the next few decades in Asia,” says Seang-Mei Saw, a physician and epidemiologist at the National University of Singapore.

The new wave isn’t genetic, Morgan says. “The gene pool can’t change that much in a generation, not even in several,” he says.

The other behavioral change that may not mesh well is near work. Human forebears didn’t read, and even those who chipped arrow points or did other fine work probably didn’t do it all day, every day. Frequent near work arrived with civilization; in many societies, it came about in the last century or two. A lot of myopia develops during childhood, and there may be some science behind the stereotypical bookworm with thick glasses. Myopia can also show up in adulthood, depending on the quantity of near work done. This is called occupational myopia.

Recent work by several researchers argues that “reading, writing and computer work will contribute to myopia, and that children who regularly spend much time on computers have a higher risk of myopia.”

 A world tour…

Source: Epidemiology (http://en.wikipedia.org/wiki/Myopia)

The global prevalence of refractive errors has been estimated from 800 million to 2.3 billion. The incidence of myopia within sampled population often varies with age, country, sex, race, ethnicity, occupation, environment, and other factors. Variability in testing and data collection methods makes comparisons of prevalence and progression difficult.

The prevalence of myopia has been reported as high as 70–90% in some Asian countries, 30–40% in Europe and the United States, and 10–20% in Africa. Myopia is less common in African people. In Americans between the ages of 12 and 54, myopia has been found to affect African Americans less than Caucasians.

Asia

In some parts of Asia, myopia is very common. Singapore is believed to have the highest prevalence of myopia in the world; up to 80% of people there have myopia, but the accurate figure is unknown. China’s myopia rate is 31%: 400 million of its 1.3 billion people are myopic. The prevalence of myopia in high school in China is 77.3%, and in college is more than 80%. However, some research suggests the prevalence of myopia in India in the general population is only 6.9%.

Europe

A recent study involving first-year undergraduate students in the United Kingdom found 50% of British whites and 53.4% of British Asians were myopic.

United States

Myopia is common in the United States, with research suggesting this condition has increased dramatically in recent decades. In 1971-1972, the National Health and Nutrition Examination Survey provided the earliest nationally representative estimates for myopia prevalence in the U.S., and found the prevalence in persons aged 12–54 was 25.0%. Using the same method, in 1999-2004, myopia prevalence was estimated to have climbed to 41.6%.

Australia

In Australia, the overall prevalence of myopia (worse than −0.50 diopters) has been estimated to be 17%. In one recent study, less than one in 10 (8.4%) Australian children between the ages of four and 12 were found to have myopia greater than −0.50 diopters. A recent review found 16.4% of Australians aged 40 or over have at least −1.00 diopters of myopia and 2.5% have at least −5.00 diopters.

Epidemic myopia in Asia

Source: http://blogs.discovermagazine.com/80beats/2012/05/12/why-are-90-of-asian-schoolchildren-nearsighted-from-doing-what-youre-doing-now/#.UTNmJ5aEXjY (Why Are 90% of Asian Schoolchildren Nearsighted? From Doing What You’re Doing Now –  By Sarah Zhang)

The sheer prevalence of nearsightedness, or myopia, among Asian schoolchildren (in Singapore, China, Taiwan, Hong Kong, Japan, and Korea) is stunning: 80 to 90% according to a recent review in the journal Lancet. In comparison, that number is just 20 to 30% in the UK. Myopia has also been on the rise in both Asia and Europe over the past few years.

In Singapore, myopia has shot up in the last 30 years among all three major ethnic groups—Chinese, Indian, and Malay—which highly suggests a environmental cause. Singaporean schoolchildren who read more than two books per week were also more likely to have myopia. How one reads physically, may have an impact too: ultra-orthodox Jewish boys, who study the Torah intensely and at a close distance while swaying, have higher myopia numbers than the girls, who don’t. Together, these observational studies suggest that high myopia rates in Asian schoolchildren are likely related to their intense educational systems.


Singapour

Change in prevalence of myopia among three ethnic groups in Singapore. The following numbers Figures are approximate and are taken from the illustration above.

                                       China             India              Malaysia

1987-1992                     48%                29%                  25%

1996-1997                     80 %              70%                  65%

2009-2010                     85%               75%                  70%

Also adapted from : http://www.sciencenews.org/view/feature/id/347738/description/Urban_Eyes – By Nathan Seppa