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Archive for November, 2012

Glasses and headaches: confusion for all!

Does your child wear glasses? If so, has he or she ever complained of headaches that improved or were eliminated with a change of prescription glasses or wearing a pair of glasses for the first time? That would be very rare, at least according to a “study” presented at the meeting of the American Academy of Ophthalmology.

This study from the Albany Medical Center in New York believes that vision problems or eye are rarely the cause of recurrent headaches in children, although headaches usually strike while the child is doing schoolwork or other visual tasks.

Photo: www.visionhelp.wordpress.com

If this sounds suspicious to you, it should.

The biggest problem: the study was retrospective. Scientists agree that only prospective studies (see below) constitute real scientific evidence. This press release claims clear evidence that vision or eye problems are rarely the cause of headaches, and that there is no correlation between the need for glasses and headaches. And what kind of study is it? A retrospective study!

Prospective studies usually have fewer potential sources of bias and confounding than retrospective studies. For this reason, retrospective investigations are often criticised.

There seems fishy, does it not? Of course! This is another effort by the association of ophthalmologists in the United States to convince the public that glasses are prescribed unnecessarily. The press release highlights the hope that this study will help to reassure parents that most cases of headaches in children are not associated with vision or eye problems, and that most headaches will disappear with time, even if the headaches usually strike while the child is doing schoolwork or other visual tasks. My eye!

A statement of this nature has broad implications, and it intended (?) to assure parents that headaches are not likely to be causes by use of vision. The authors prefer to direct the public to a pediatrician that will decide if a visual examination is necessary rather than consult an optometrist!

The burden of proof for such claims is on the investigators, because it runs counter to gold standard published research.  Acknowledged by all parties to be one of the best studies ever published jointly by Optometry and Ophthalmology regarding children’s visual symptoms, the CITT noted that 32% of all children with convergence insufficiency (CI) reported headaches occurring fairly often or always while reading or doing close work.  Given that the prevalence of CI occurs to a greater degree in the population studied than strabismus, amblyopia, and high ametropia combined, and that no provision is made in vision screenings by pediatricians or school nurses to detect the condition, this study stands to confuse rather than clarify the role of vision conditions regarding headaches in children.

Photo : http://www.freedigitalphotos.net/

The authors report that 13.9% (22 children) of their population experienced headaches associated with visual tasks.  This means that 86.1% (136 children of a total of 158) of their population had a headache type for which visual input was not a factor, and therefore a severely skewed population in which one would not expect to find that glasses had more than a chance influence.

The authors did not even look at reasons for the disappearance of headaches in children over time. We must understand that headaches are mostly caused by the use of near vision (reading, writing, video games, etc.), often there is an eye alignment problem or a focusing problem. If the problem persists, the visual system will make significant concessions to solve the problem. Most of the time, as an adaptation to visual stress, we will see the child becoming myopic. Headaches do not go away without other visual problems appearing. But the authors did not take this into account…

It is unfortunate that a study so scientifically questionable has made ​​so many headlines everywhere…

Here is the link to the study:

http://www.aao.org/newsroom/release/20121112a.cfm

Adapted from the VisionHelp Blog: http://visionhelp.wordpress.com/

Vision Problems of Children with Individualized Education Programs

Much of learning is associated with visual cues, so children with vision-related problems may find it difficult to keep up with their peers in an academic setting. In order to assess the relationship between success in an academic setting and vision-related problems, we compared the prevalence of vision-related problems between children with Individualized Education Programs (IEPs) to population-based samples from the literature.

An IEP is a written statement that includes a child’s present levels of academic achievement and functional performance, measurable academic and functional goals, alternate assessments aligned to alternate achievement standards (if necessary), and a description of necessary special education services, supplementary aids, and accommodations. An IEP is written by a team of professionals that may include school psychologists, teachers, school nurses, speech and language teachers, and medical specialists in order to set measurable goals and establish a guide for the child’s special learning needs.

Eye care professionals completed a visual examination on children with an IEP. The prevalence of a variety of conditions exhibited by children with IEPs was compared to prevalence rates reported in the literature.

Data were analyzed for 255 children reported to have an IEP. The average age of the children was 9.6 years.

Higher prevalence rates were reported for IEP patients than for samples from the literature for myopia (9 of 13 studies), hyperopia (10 of 13 studies), astigmatism (6 of 9 studies), anisometropia (myopia oy hyperopia different in each eye) (3 of 4 studies), and strabismus (6 of 6 studies). The entering distance visual acuity of IEP patients was 20/40 or worse for 23.7% of them, but 7.2% of eyes still had a visual acuity worse than 20/40 after correcting their problem. Of the children who required some form of treatment, 124 (69.3%) had better than 20/40 entrance visual acuity in both eyes.

Many of these vision problems would solely be undetected by vision screenings based on distance visual acuity, illustrating the need for comprehensive vision examinations for children who are struggling academically.

(1)   Walline JJ, Johnson Carder ED. Vision Problems of Children with Individualized Education Programs Journal of Behavioral Optometry. Volume 23/2012/Number 4.

It has been estimated that 80% of learning is obtained through vision. Although there is no scientific evidence for this statement, few disagree with the assertion. Scientists have found significantly lower achievement test scores, as well as reduced letter and word recognition, receptive vocabulary, emergent orthography, and verbal and performance intelligence quotients among children with uncorrected hyperopia. Furthermore, children with learning disabilities exhibit a greater prevalence of vision-related problems than the entire population. Certain vision problems that may affect learning, but not all, are related to refractive problems (hyperopia, astigmatism and less with myopia), so vision examinations may provide helpful information in the management of children with learning disabilities.

Source: VisionHelp Blog – Dr Fortenbacher, OD FCOVD:

Conclusion

But, what if a child with an IEP also has a vision problem? Wouldn’t that pose a risk to the child responding effectively to their IEP?   To attempt to answer this question, 3 states in the US (Illinois, Kentucky and Missouri) have mandatory eye examinations for children before Kindergarten. Only Arkansas, North Carolina, Oklahoma and Massachusetts require examinations for children who fail a school vision screening. And only Ohio and Massachusetts require examinations for children with learning difficulties. Sixteen states do not even require vision screenings for children.  Regardless of the state laws, when an eye examination has not been performed by a qualified eye doctor, the school will typically provide a vision screening to determine that vision is functioning “normally”. However, here is where problems begin to surface. Vision screenings are predominantly an eye sight test. That is, if the child’s visual acuity (eye sight) is better than 20/40 they pass the vision screening!

Even more critical to the question of the validity of a school vision screening was another startling conclusion of the team which found that out of the 179 that required treatment, 124 (69%) of the children with IEPs would have passed the school vision screening test. That is to say, nearly 70% of those children with an IEP were identified with treatable vision problems and yet would pass the vision screening because their vision problem did not affect their distant eye sight!

If you are a teacher, insist that any child who has an IEP be seen by an eye doctor who will provide a thorough vision evaluation and provide you with feedback about the results.

If you are a parent, whose child struggles in reading and learning and/or has an IEP, it is imperative that you seek help by a doctor who is thorough, enjoys working with children and either provides office-based vision therapy or will refer you to a qualified doctor who provides office-base optometric vision therapy.

WHAT IS AN IEP?

http://www.edu.gov.on.ca/eng/general/elemsec/speced/guide/specedpartee.pdf

An IEP is a written plan. It is a working document that describes the strengths and needs of an individual exceptional pupil, the special education program and services established to meet that student’s needs, and how the program and services will be delivered. It also describes the student’s progress.

An IEP should be based on a thorough assessment of the student’s strengths, interests, and needs. It should identify specific goals and expectations for the student, and should explain how the special education program will help the student achieve the goals and expectations set out in the plan. The special education program and services the IEP describes should be modified as necessary by the results of continuous assessment and evaluation.

A student’s IEP should be developed, implemented, and monitored in a collaborative manner. The educational growth of a student is best accomplished through the mutual efforts of, and close communication among, the student, the student’s parent, the school, the community, and other professionals involved with the student. The IEP provides an opportunity for all those involved with the student to work together to provide a program that will foster student achievement and success.

In summary, an IEP is…

  • a summary of the student’s strengths, interests, and needs and of the expectations for a student’s learning during a school year that differ from the expectations defined in the appropriate grade level of the Ontario curriculum;
  • a written plan of action prepared for a student who requires modifications of the regular school program or accommodations;
  • a tool to help teachers monitor and communicate the student’s growth;
  • a plan developed, implemented, and monitored by school staff;
  • a flexible, working document that can be adjusted as necessary;
  • an accountability tool for the student, his or her parents, and everyone who has responsibilities under the plan for helping the student meet his or her goals and expectations;
  • an ongoing record that ensures continuity in programming;
  • a document to be used in conjunction with the provincial report card.

Young myopes: go play outside?

Introduction

An early study in Australia reported that playing outdoors more could have a link with a lower prevalence of myopia in children was published in 2008 by Kathlyn Rose and colleagues (1) ; this study was impressive with the number of children involved: over 4000 children were included in the “Sydney Myopia study”, which took place between 2003 and 2005.

The authors showed that higher levels of outdoor activity (sports and leisure) were associated with more hyperopic refractions and lower myopia prevalence among students 12 years of age. Students who performed a lot of near work indoor and spent the least time playing outside showed less hyperopia and more myopia. The opposite is also true.

The same research team (2) measured the presence of myopia in two of age- and ethnicity-matched primary school children participated: 124 from the Sydney Myopia Study and 628 from the Singapore Cohort Study on the Risk Factors for Myopia.

The prevalence of myopia in 6- and 7-year-old children of Chinese ethnicity was significantly lower in Sydney (3.3%) than in Singapore (29.1%) (P< .001). The prevalence of myopia in 1 or more parents was 68% in Sydney and 71% in Singapore. Children in Sydney read more books per week (P < .001) and did more total near-work activity (P = .002). Children in Sydney spent more time.

On outdoor activities (13.75 vs 3.05 hours per week; P < .001), which was the most significant factor associated with the differences in the prevalence of myopia between the 2 sites.

They then examined teenage children (3) (1249 participants) in the Singapore Cohort study Of Risk factors for Myopia (SCORM), during 2006.

The mean total time spent on outdoor activity was 3.24 h/day. The total outdoor activity (h/day) was significantly associated with less myopia. In addition, the total time spent outdoors was associated with significantly less myopia. Total sports time was also significantly associated with less myopia, but not indoor sports.

Participants who spent more time outdoors were less likely to be myopic. Thus, outdoor activity may protect against development of myopia in children, supporting recent Australian data (see above).

Other studies have followed thereafter and future research will surely come.

Other studies

In 2010, Deng (4) investigated the association of children’s refractive errors with their visual activities assessed by questionnaire in the school year and summer break (June, July, and August).

During the school year, myopes spent significantly fewer hours (8.25 ± 6.24 h/week) than non-myopes (10.95 ± 5.95 h/week) in sports/outdoor activity (p < 0.05). In addition, myopes (12.78 ± 9.28 h/week) watched more television than non-myopes (8.91 ± 5.95 h/week) (p = 0.02). No significant refractive group differences were found for other activities.

A new finding is the high number of sports/outdoor activity hours for both myopes and non-myopes during the summer break, which may contribute to slowed eye growth in all children during these 3 months.

Guggenheim (5)  followed participants in the Avon Longitudinal Study of Parents and Children (ALSPAC) who were assessed at ages 7, 10, 11, 12, and 15 years, and classified as myopic (≤-1 diopters) or non myopic.  Physical activity at age 11 years was measured objectively using an accelerometer, worn for 1 week. Time spent outdoors was assessed via a parental questionnaire administered when children were aged 8-9 years.

Time spent outdoors was predictive of incident myopia independently of physical activity level. The greater association observed for time outdoors suggests that the previously reported link between “sports/outdoor activity” and incident myopia is due mainly to time outdoors rather than physical activity.

Dharani et al. (6) analyzed the time spent outside in, using a log notes and a light meter over a period of 1 week in Singapore for 117 children aged 6-12 with and without myopia. All children wore the light meter for 1 week and parents completed the log outdoor activities for children for 7 days.

The agreement between the light meter measures and the activity logbook was poor to fair. Both instruments measure different parameters, without doubt, time spent outside and the light intensity that results, and it does not seem a useful approach to understand the different aspects of risk in future studies for myopia.

Donovan (7) has analysed seasonal variations in the myopic progression of Chinese children.

They examined a total of 85 Chinese children with myopia between -0.75 D and -3.50 D and astigmatism ≤ -1.50 D, who wore glasses to see far away. They measured refraction and the axial length of the eye at 6 month intervals. The growth rate of the right eye was defined for the first and second 6 months of the study and classified according to “summer”, “autumn”, “winter” or “spring.”

The average increase of 6 months was -0.31 ± 0.25 D for the summer, -0.40 ± 0.27 D for the fall, -0.53 ± 0.29 D for the winter, and -0.42 ± 0.20 D in the spring (p <0.001). The increase in axial length was 0.17 ± 0.10 mm for the summer, 0.24 ± 0.09 mm for autumn, 0.24 ± 0.09 mm for the winter, and 0.15 ± 0.08 mm for the spring (p <0.001). In addition, data for summer and winter were different from each other for the progression of myopia and axial elongation.

Myopia progression in summer months was approximately 60% of that seen in winter, and axial elongation was likewise significantly less in summer. It is unclear whether more time spent outdoors in summer vs. winter is a contributing factor, or the difference in progression rates is a result of “seasonal” variations in the intensity or amount of close work performed.

Jones-Jordan (8) has also investigated the association between myopia progression and time spent outdoors and in various visual activities.

Their results indicate that the number of hours of reading for pleasure per week was not significantly associated with annual myopia progression, nor were the other near activities. The magnitude of effects was clinically small.

Despite previous associations between time spent outdoors and the risk of developing myopia, these authors were unable to obtain the same results …

Conclusion:

One of the surprises of recent research is the importance of how the increased time spent outdoors helps prevent myopia. At present, it seems that 14 hours per week or more outside are significantly effective in reducing the progression of myopia.

Why this surprising relationship? Here are some suggestions:

• Exposure to sunlight increases the production of vitamin D (vitamin D is produced by the skin, using sunlight)? But a study showed that blood concentrations of this vitamin is not significantly different in children who spend more time outdoors than others…

• Exposure to sunlight increases the production of chemicals in the retina such as dopamine which controls the growth of the eye?

• Children often look away when they play outside?

• Exposure to beneficial microorganisms (production of serotonin, which is part of the signaling system in the retina of the eye to counter the growth of the eye)?

We know it is not sports and physical activities are involved. The benefits are possible for the children to play outside without organized sport activity.

References:

(1) Rose KA, Morgan IG, Ip J, Kifley A, Huynh S, Smith W, Mitchell P.Outdoor activity reduces the prevalence of myopia in children. Ophthalmology. 2008 Aug;115(8):1279-85.

(2) Rose KA, Morgan IG, Smith W, Burlutsky G, Mitchell P, Saw SM. Myopia, lifestyle, and schooling in students of Chinese ethnicity in Singapore and Sydney. Arch Ophthalmol. 2008 Apr;126(4):527-30.

(3) Br J Ophthalmol. 2009 Aug;93(8):997-1000. Epub 2009 Feb 11. Outdoor activity and myopia in Singapore teenage children. Dirani M, Tong L, Gazzard G, Zhang X, Chia A, Young TL, Rose KA, Mitchell P, Saw SM.

(4) Deng L, Gwiazda J, Thorn F. Children’s refractions and visual activities in the school year and summer. Optom Vis Sci. 2010 Jun;87(6):406-13.

(5) Mutti DO, Marks AR. Blood levels of vitamin D in teens and young adults with myopia. Optom Vis Sci. 2011 Mar;88(3):377-82.

(6) Dharani R, Lee CF, Theng ZX, Drury VB, Ngo C, Sandar M, Wong TY, Finkelstein EA, Saw SM. Comparison of measurements of time outdoors and light levels as risk factors for myopia in young Singapore children. Eye (Lond). 2012 Jul;26(7):911-8. doi

(7) Donovan, L, Sankaridurg, P, Ho, A. Chen, X. Lin, Z. Thomas, V. Smith, E L. III, Ge, J. Holden, B. Myopia Progression in Chinese Children is Slower in Summer Than in Winter.  Optometry & Vision Science. 89(8):1196-1202, August 2012.

(8) Jones-Jordan LA, Sinnott LT, Cotter SA, Kleinstein RN, Manny RE, Mutti DO, Twelker JD, Zadnik K; for the CLEERE Study Group.Time Outdoors, Visual Activity, and Myopia Progression in Juvenile-Onset Myopes. Invest Ophthalmol Vis Sci. 2012 Oct 15;53(11):7169-7175.