(From Pediatric Directions, Issue 39)
Convergence insufficiency and accommodation are conditions that affect reading abilities in children. Difficulties with either will interfere with the physical act of reading, but not with decoding. Treatment of these conditions will allow a child to read more comfortably for longer periods of time, but will not directly improve decoding or language comprehension. The reported incidence of convergence insufficiency is between 2.4 and 8.3 percent of the general population.
Research has shown that most reading disabilities are not caused by altered visual function. This can be exemplified by the majority of children with reading issues who excel at playing video games. These games require intense visual perception, visual processing, attention, concentration, eye movements, convergence, accommodation and hand-eye coordination. It follows that if these issues were a major cause of reading disability, children with these issues would also struggle with, or object to, prolonged videogame activities1.
Pediatricians and ophthalmologists often evaluate children who are experiencing learning and reading difficulties. Studies have shown that between 5 and 17 percent of children have learning disabilities in any number of areas, including speaking, reading, listening, spelling, writing, reasoning, concentrating and problem solving. These disabilities are complex, multifactorial and often require complex solutions. Many practitioners and parents are anxious to find solutions because of the importance of early detection. Using evidence-based treatment is essential to obtain best possible outcomes.
The importance of these issues was addressed in a joint policy statement by the American Academy of Pediatrics, the American Academy of Ophthalmology, the American Association for Pediatric Ophthalmology and Strabismus, and the American Association of Certified Orthoptists. Being familiar with the information in this policy statement is vital in helping the physician and parents understand how to effectively deal with these issues. For instance, approximately 80 percent of people with learning disabilities have dyslexia. Dyslexia is a primary reading disorder that results from a written word processing abnormality in the brain. Symptoms include difficulties with accurate sight word recognition, poor spelling and word decoding. These issues are typically unexpected as dyslexic children are very bright in other areas, such as math and science. There is a strong genetic component to dyslexia as it occurs in 40 percent of the siblings, children or parents of an affected individual. However, dyslexia also occurs in those without a family history.
It is important to correctly identify dyslexia as it is often confused with other secondary forms of reading difficulty caused by mental retardation, experiential or instructional deficits, and hearing and visual deficits. Studies suggest the pathophysiology behind dyslexia seems to stem from the dyslexic individual utilizing different parts of the brain than normal individuals when reading. The good news is these dyslexia-specific brain abnormalities have been shown to improve after successful phonologically based intervention.
Another frequently encountered issue is problems with eye movements known as saccades. A saccade is a short duration, high velocity, small jumping eye movement used for reading. Children with dyslexia frequently have abnormal saccades. These abnormalities resolve when reading content is adjusted for their ability. Decoding comprehension rather than a primary problem with oculomotor control is responsible for slow reading and abnormal saccades. Thus, the abnormal saccadic pattern seen in readers with dyslexia is a symptom and not a cause of the dyslexia. In addition, children with dyslexia often lose their place while reading because of their struggle to decode a letter or word combination and not because of a visual tracking problem.
Diagnosing and Treating Convergence Insufficiency
Convergence insufficiency is an ocular condition seen clinically, which can cause reading issues in children. The disorder is characterized by the inability to comfortably maintain binocular eye alignment (focus) at near. As cited earlier in this article, the reported incidence of convergence insufficiency is between 2.4 and 8.3 percent of the general population.
Case Study: Convergence Insufficiency
A 9-year-old female was referred to Nationwide Children’s Ophthalmology Department in 2008, with complaints of reading difficulty, blurred vision, headaches and double vision when reading. She had been having these symptoms for several months and it was affecting her reading and writing at school. After a complete dilated ophthalmological exam, she was diagnosed with severe convergence insufficiency. She was given reading glasses and was to return for a follow-up visit at one month.
At her follow-up visit, the patient reported that she was wearing her glasses at school and when doing her homework. Her complaints of blurred vision had slightly improved with the glasses but she was still having headaches and double vision (at near). Ophthalmologists re-evaluated her objective clinical measures and compared to her initial exam, they were still reduced. She was prescribed home-based computer orthoptic exercises. Her progress was monitored online. Patients can also monitor their progress at home with a printable progress report, which can be brought in with each follow-up visit. The eye exercise program works to improve fusional vergences (which are typically reduced in a child with convergence insufficiency) and they are done for six minutes/day.
She was also given convergence exercises, which help improve a patient’s near point of convergence and are done three times/day. She began to show significant improvement with her symptoms and objective clinical measures at her follow-up visits. After three months of performing her home-based orthoptic exercises, her objective clinical measures improved to within normal limits and her symptoms were resolved completely. Her reading also improved, and she was no longer having headaches or double vision when she read. She continued her home exercise regimen for another three months even though her clinical measures and symptoms had improved to avoid any regression or recurrence of symptoms.
Learn more about what Nationwide Children’s ophthalmologists are doing regarding convergence insufficiency and other ocular indications.
David L. Rogers, MD, is a member of the Department of Ophthalmology at Nationwide Children’s. Dr. Rogers graduated from Wright State University School of Medicine in 2002. He then went on to complete his residency in ophthalmology and subsequently a fellowship in pediatric ophthalmology and adult strabismus at Indiana University School of Medicine. His clinical interests include pediatric and adult strabismus, pediatric cataract, glaucoma and low vision. He has a strong interest in clinical research. His research interests include telemedicine for retinopathy of prematurity (ROP), pediatric vision screening, pediatric cataract and outcomes in strabismus surgery.
Angela Serna, BAppSc(Orthoptics), MPH, is an orthoptist at Pediatric Ophthalmology & Associates at Nationwide Children’s. She graduated from the University of Sydney, Australia with a Bachelor of Applied Science in Orthoptics (Hons) in 1999. She has worked in a pediatric ophthalmology setting for the past 12 years both in Australia and Columbus, Ohio. She completed her public health master’s degree program at The Ohio State University in 2007. She has a strong interest in clinical research and teaching. Her research interests include convergence insufficiency and strabismus.
J AAPOS. Jun;15(3);230-3. Epub 2011 Jun 12. The effect of surgical preparation technique on the bacterial load of surgical needles and suture material used during strabismus surgery. Rogers DL, Chheda L, Ford C, Marcon M, Fellows RR, Rogers GL, Bremer DL, McGregor ML, Golden RP, Cassady CB.
J AAPOS. 2011 Apr; 15(2):140-3. Epub 2011 Mar 31. Treatment of sumptomatic convergence insufficiency with a home-based computer orthoptic exercise program. Serna A, Rogers DL, McGregor ML, Golden RP, Bremer DL, Rogers GL.