Common Pediatric Eye Diseases

8/21/14

In the third of this series, Buddy Russell, from the Emory University Eye Center, provides a great overview of common pediatric eye diseases.

Some Conditions Frequently Seen in Pediatrics

A basic understanding of some of the conditions that may be present in pediatric patients is important to not only know what they are but also understand well enough to explain to the parent or caregiver. The following is intended to be an overview of some of those conditions and not a complete explanation.Girl with eye chart-common pediatric eye diseases

  1. Nystagmus – Nystagmus is a vision condition in which the eyes make repetitive, uncontrolled movements, often resulting in reduced vision. These involuntary eye movements can occur from side to side, up and down, or in a circular pattern. As a result, both eyes are unable to hold steady on objects being viewed. Unusual head positions and head nodding in an attempt to compensate for the condition may accompany nystagmus. Most individuals with nystagmus can reduce the severity of their uncontrolled eye movements and improve vision by positioning their eyes to look to one side. This is called the “null point” where the least amount of nystagmus is evident. To accomplish this they may need to adopt a specific head posture to make the best use of their vision. The direction of nystagmus is defined by the direction of its quick phase (e.g. a right-beating nystagmus is characterized by a rightward-moving quick phase, and a left-beating nystagmus by a leftward-moving quick phase). The oscillations may occur in the vertical, horizontal or torsional planes, or in any combination. The resulting nystagmus is often named as a gross description of the movement, e.g. downbeat nystagmus, upbeat nystagmus, seesaw nystagmus, periodic alternating nystagmus. Having nystagmus affects both vision and self-concept. Most people with nystagmus have some sort of vision limitations because the eyes continually sweep over what they are viewing, making it impossible to obtain a clear image. If a refractive error is found, contact lenses may be the most effective way of obtaining best-corrected vision.
  2. Strabismus – Strabismus is any misalignment of the eyes. It is estimated that 4% of the U.S. population has strabismus. Strabismus is most commonly described by the direction of the eye misalignment. Common types of strabismus are esotropia (turn in), exotropia (turn out), hypotropia (turn down), and hypertropia (turn up). Eye misalignment can cause amblyopia in children. When the eyes are oriented in different directions, the brain receives two different visual images. The brain will ignore the image from the misaligned eye to avoid double vision, resulting in poor vision development of that eye. Also, an eye that sees poorly tends to be misaligned. The goal of strabismus treatment is to improve eye alignment, which allows for better work together (binocular vision). Treatment may involve eyeglasses, contact lenses, eye exercises, prism, and / or eye muscle surgery.
  3. Amblyopia – Amblyopia, sometimes called a “lazy eye,” occurs when one or both eyes do not develop normal vision during early childhood. Babies are not born with 20/20 vision in each eye but must develop it between birth and 6-9 years of age by using each eye regularly with an identical focused image falling on the retina of each eye. If this does not occur in one or both eyes, vision will not develop properly. Instead, vision will be reduced and the affected eye(s) are said to be amblyopic. This common condition, affecting up to 4% of all children, should be diagnosed and treated during infancy or early childhood to obtain optimum three-dimensional vision and to prevent permanent vision loss. What causes amblyopia?
      • Misaligned eyes (strabismus)
        Misaligned eyes are the most common cause of amblyopia. When both eyes are not aimed in exactly the same direction, the developing brain “turns off” the image from the misaligned eye to avoid double vision and the child uses only the better eye — the dominant eye. If this persists for a period even as short as a few weeks, the eye will not connect properly to the visual cortex of the brain and amblyopia will result.
      • Unequal refractive error (anisometropia)
        Unequal refractive error is an eye condition in which each eye has a different refractive error and therefore both eyes cannot be in focus at the same time. Amblyopia occurs when one eye (usually the eye with the greater refractive error) is out of focus because it is more nearsighted, farsighted or astigmatic than the other. Again, the brain “turns off” the image from the less focused eye and this eye will not develop normal vision. Because the eyes often look normal, this can be the most difficult type of amblyopia to detect and requires careful vision screening of acuity measurements at an early age. Treatment with glasses or contact lenses to correct the refractive error of both eyes, sometimes with part-time patching of the better seeing eye, is necessary in early childhood to correct the problem.
      • Obstruction of or cloudiness (deprivation)
        Obstruction of or cloudiness in the normally clear eye tissues may also lead to amblyopia. Any disorder that prevents a clear image from being focused can block the formation of a clear image on the retina and lead to the development of amblyopia in a child. This often results in the most severe form of amblyopia. Examples of disorders that can interfere with getting a clear image on the retina are a cataract or cloudy lens inside the eye, a cloudy and or irregular shaped cornea, or a droopy upper eyelid (ptosis) or eyelid tumor.It is not easy to recognize amblyopia. A child may not be aware of having one normal eye and one with reduced vision. Unless the child has a misaligned eye or other obvious external abnormality, there is often no way for parents to tell that something is wrong. In addition, it is difficult to measure vision in very young children at an age in which treatment is most effective.To treat amblyopia, a child and their caregiver must be encouraged to use the weaker eye. This is usually accomplished by patching the stronger eye. This covering of the stronger eye with an adhesive patch, an cclude contact lens or temporary surgery often proves to be a frustrating and difficult therapy. Patching will often continue for weeks, months, or even years in order to restore normal or near normal vision and maintain the improvement in the amblyopic eye. Occasionally, blurring the vision in the good eye with eye drops or lenses to force the child to use the amblyopic eye treats amblyopia. In some cases, cataract surgery or glaucoma surgery might be necessary to treat form deprivation amblyopia. Patching may be required after surgery to improve vision, and glasses or contact lenses may be required to restore appropriate focusing.Surprising results from a nationwide clinical trial in 2005 show that many children age seven through 17 with amblyopia may benefit from treatments that are more commonly used on younger children.
        Treatment improved the vision of many of the 507 older children with amblyopia studied at 49 eye centers. Previously, eye care professionals often thought that treating amblyopia in older children would be of little benefit. The study results, funded by the National Eye Institute (NEI), appear in the April issue of Archives of Ophthalmology.
  4. Congenital Cataract – A congenital cataract, or clouding of the crystalline lens is present in 2-3 per 10,000 live births of children. The presence of a visually significant cataract in a child is considered an urgent disorder. The resultant form deprivation of vision requires immediate surgery to remove the obstruction, prompt optical correction and amblyopia therapy in unilateral cases. Until the 1970s, it was generally believed that there was no means of restoring the vision in an eye with a unilateral congenital cataract. However, subsequent studies demonstrated that excellent visual results could be obtained with early surgical treatment coupled with optical correction with a contact lens and patching therapy of the fellow eye. However, treatment results continue to be poor in some infants with unilateral congenital cataracts due to a delay in treatment or poor compliance with contact lens wear or patching therapy of the fellow eye. The Infant Aphakia Treatment Study (IATS) was designed to compare the visual outcomes in children 1 to 6 months of age with a unilateral congenital cataract randomized to optical aphakic correction with contact lenses or an intraocular lens (IOL). Children randomized to IOL treatment had their residual refractive error corrected with spectacles. Children randomized to no IOL had their aphakia treated with a contact lens. In previous publications we have shown that the visual results are comparable for these two treatments at 1 year of age, but significantly more of the infants randomized to IOL implantation required additional intraocular surgeries.
  5. Accommodative Esotropia – Accommodative esotropia refers to a crossing of the eyes caused by farsightedness. Accommodative esotropia is a type of strabismus. Children who are farsighted easily and automatically focus on objects at distance and near through accommodation. As a result, a child who is farsighted usually does not have blurred vision. However, in some children who are farsighted, this accommodative effort is associated with a reflex crossing of the eyes. Accommodative esotropia can begin anywhere from 4 months to 6 years of age. The usual age of onset is between 2 and 3 years of age.Full-time use of the appropriate hyperopic glasses prescription or contact lenses will often control the esotropia. When wearing the correction, the child will not need to accommodate and hence the associated eye-crossing reflex will disappear. However, after removing the prescribed correction, the crossing will reappear, perhaps even more than before the child began wearing the correction. Sometimes the correction will only cause the crossing to disappear when the child views a distant object. However, when gazing at near objects, crossing may persist despite the use of the correction. In these circumstances, a bifocal lens is often prescribed to permit the child to have straight eyes at all viewing distances. One potential advantage of contact lenses compared to spectacles when correcting hyperopic powers is the decrease in accommodative demand. The increased effort to converge the eyes with spectacles requires one to over come the resultant base out prism when viewing a near object.

 

Buddy Russell - pediatric contact lensesBuddy Russell, FCLSA, COMT
Associate, Specialty Contact Lens Service
Emory University Eye Center

Treatment Options For Children

8/19/14

Here is part two in Buddy Russell’s series; this one focusing on contact lenses as a treatment option for children.

We Are Not Born With Good Vision

The human visual system at birth is poorly developed, but rapidly becomes the remarkable combination of nerve tissue, muscles and optics that provide us with the sense of vision. Those babies born with “perfect” eyes have only the opportunity to develop normal vision. The information processed by the eyes is sent directly to the brain and is interpreted as vision.Toddler looking through glasses - treatment options for children During the first few weeks, the child sees shapes, lines and space between objects. The child’s visible world is most usable within 8-14 inches of his/her eyes. During this time, the eyes may appear to wander. After about a month or so, the normal child’s eyes will appear more coordinated and they start to show more interest in looking at objects. It is usually in the third month that a child who has normal eyes can fix and follow on a near object. The growth of the eye is a dynamic process, influenced by genetics and the environment.
Early detection of any eye problem is key to treating the disorder. The prevalence of vision problems in children is higher than you might think. For example:

  • 1 in 10 children are at risk from undiagnosed vision problems
  • 1 in 25 will develop strabismus
  • 1 in 30 will be affected by amblyopia
  • 1 in 33 will show significant refractive error
  • 1 in 100 will exhibit evidence of eye disease
  • 1 in 20,000 children have retinoblastoma

As a result of his granddaughter and her eye problem, former President Jimmy Carter initiated a program in 2002 called InfantSEE. This program allows children to have an eye exam at a very young age at no charge to the family. Participating eye doctors provide a more thorough exam than the busy pediatrician. As a result, there is a greater opportunity to detect and treat eye disorders that may otherwise go undetected.

“Have to” Contact Lenses

Fitting pediatric patients is not usually about routine visits and patients who want to wear contact lenses. It is about critical and often urgent situations and patients who have to wear contact lenses. The more common medical indications for contact lenses can be categorized into three groups; anisometropia, irregular corneal astigmatism and “large” refractive errors.

Anisometropia

One of the more common conditions potentially leading to a permanent loss of vision in a young patient is anisometropia. This difference in the refractive errors of the two eyes can lead to suppression of the less clear image. As a result of the non-focused eye, the brain of a young patient simply turns off the blurred eye. Early detection is key to successful treatment. Following the diagnosis of this problem being present, simply correcting the refractive error may be enough. However, it has been reported that as little as one diopter difference between the two eyes corrected with spectacles and the resultant anisokonia, can lead to foveal suppression impacting stereopsis and depth perception. The use of a contact lens or contact lenses alters the effective image size due to the vertex distance being zero compared to either the magnification or minification of the image size due to the vertex distance with spectacles. One of the most severe examples of this condition would be a child with a unilateral congenital cataract and managed with spectacles postoperatively.

Irregular Corneal Astigmatism

Whether acquired or congenital, the presence of irregular corneal astigmatism of the anterior curve of the cornea is best managed with a contact lens. This condition is to be considered urgent if the patient is of a young age. The eye may forever loose the opportunity to be corrected as the resultant amblyopia develops over a short period of time. By neutralizing the corneal irregularities with a contact lens, the eye of a young child will hopefully gain enough vision improvement to avoid the potential permanent loss.
Obviously, patching the better eye may also be necessary if the treated eye’s vision is not as correctable as the unaffected eye. The length of time the child is to be patched is to be determined by the pediatric ophthalmologist or optometrist, as this area of treatment is sometimes controversial. The factors that are considered include the level of vision obtained, age of the child and the condition of the other eye.

Large Refractive Errors

The optics of spectacle correction in high powers have inherent properties that include distortion, prismatic effect and minification / magnification. For instance, the decrease in image size when one views an object through high minus spectacles may result in less vision. This decrease in image size may impact the opportunity to fully develop normal vision in a young child. The smaller image size that is due to the vertex distance of spectacles may be better managed with a contact lens that has a vertex distance of zero thus providing a larger image. This larger image size often increases best-corrected vision.

“Fitting” the Caregiver

Arguably, the most important factor with young children having a good outcome is the parents / caregivers. The technical challenges that exist in these cases are secondary to the ability the fitter must possess to effectively explain and train the person or persons that will take care of the child outside of the office. They must be your partner in the child’s treatment. They must understand the urgency of the situation, they must understand the seriousness of the problem, they must be trained to properly apply, remove and care for the lens / lenses, they must also follow any and all instructions concerning the child. Many of these parents struggle with feelings of nervousness, guilt and sadness. My strategy is to be sensitive to their feelings but not let them feel sorry for themselves too long as the clock is ticking. I provide verbal instructions, written instructions, videos, my email address and a 24-hour phone number. I welcome the caregiver to ask any question at any time. I do my best to let them know that I do care and that I want them and their child to be successful. I am tough on them. There is no good excuse not to do as I have instructed them to do.

When the child and the parent / caregiver are convinced that I am confident in my ability and they know that I do care, the partnership develops as we walk the path together. I want the child to know that they are coming to see me. I want them to know I will reward their cooperation with all phases of the visit. This positive reinforcement may be in the form of a piece of candy, a small toy or just a sticker when the child allows me to see their eye, measure their cornea or intraocular pressure or they just tell me what they can see. Kids love to please us just like they love to please their parents. Reward them for it. Whether you consider this approach bribery or positive reinforcement, it works.

Buddy Russell - pediatric contact lensesBuddy Russell, FCLSA, COMT
Associate, Specialty Contact Lens Service
Emory University Eye Center

Pediatric Contact Lenses

8/14/14

Because August is Children’s Eye Health Month we are pleased to present a four-part series on pediatric vision issues and contact lenses by Buddy Russell, FCLSA, COMT. With over thirty years experience fitting contact lenses, Buddy is currently an associate of the specialty contact lens service at Emory University Eye Center in Atlanta, Georgia. Buddy is a clinical instructor in Emory’s Ophthalmic Technology Program and teaches students and ophthalmology resident’s contact lens technology. 

Child refractive exam - pediatric contact lensesHe is a licensed dispensing optician, a Fellow member of CLSA and has been certified by JCAHPO as a Certified Ophthalmic Medical Technologist. He lectures at national and international meetings on contact lens related topics. Buddy has written articles for a number of publications, two chapters for CLSA’s advanced training manual and is a peer reviewer for the Cornea publication. He is also a contributing editor for CLSA’s Eyewitness journal. His current areas of research include pediatric aphakia and keratoconus. He joined the faculty at TVCI in 2006.

The first article will examine that pediatric contact lenses for children go beyond vision correction, the second will explore lenses as a treatment option, the third will look at a variety pediatric eye conditions and the final post will discuss the contact lens fitting challenges you face when you work with children.

Introduction

Working with the pediatric patient and their caregivers / family can be challenging, rewarding, fun, and yet sometimes frustrating. Many of these cases often include factors that are unique to the young patient. In addition to the technical challenges of obtaining the objective data, the fear of uncertainty is often present. The uncertainty of the unknown can either paralyze you or motivate you to step up and simply do what must be done.

The Definition May Vary

The definition of pediatric contact lens fitting can be different to different people. The fitter who works with the occasional twelve-year-old neophyte wearer will define pediatric fitting different from the person that works with babies on a routine basis. Pediatrics is generally defined as a branch of medical care that deals with infants, children and adolescents. The word pediatrics is derived from two Greek words (pais = child and iatros = healer), which means healer of children. Are you a “healer of children” or do you tend to feel better about someone else assuming the challenge and responsibility? This article will discuss some of the conditions, contact lens indications, fitting techniques and challenges that are present with the young patient.

Refractive Indications

What age is “appropriate “ to fit a contact lens on a child? In the absence of a medical indication, Jeff Walline, OD and his colleagues have addressed the answer to this question in the published literature. In addition, the American Academy of Optometry published a position paper in 2004 that stated that by the age of eight, a child was able to handle contact lenses and assume some degree of responsibility. We are all aware that not all eight year olds are capable of dealing with contact lenses. For that matter, not all eighteen year olds are mature enough to assume responsibility for anything. Some of the concerns that a contact lens practitioner may have in fitting these young children include the risk of safety to the child’s health, too much chair time, physical limitations, lack of hygiene, and lack of maturity. These are all legitimate concerns when you consider the child can see well with spectacles.

What does the literature reveal concerning these questions and concerns? Are the answers there?

CLIP Study

The Contact Lens In Pediatrics study compared 169 neophyte wearers in two age groups (children age 8-12 and teens age 13-17) over a period of three months. The summary of the clinical findings in the publication is that adverse events was low and the younger children took a little longer to train application and removal of the contact lenses. The more impressive outcomes from this study was determined by a tool used more frequently in child psychology referred to as the Pediatric Refractive Error Profile (PREP) survey. The PREP survey is a clinically validated quality of life instrument to assess how a child “sees” him or herself. This 26-question survey revealed that contact lenses improved the child’s self image in regards to their appearance, increased confidence in themselves while participating in activities and overall satisfaction of their form of vision correction. These findings were consistent in both age groups. More than 80% of both age groups found contact lenses easy to clean and take care of as all participants were fitted with 2-week disposable soft lenses and used a multipurpose disinfection care system.

The ACHIEVE Study

The Adolescent and Child Health Initiative to Encourage Vision Empowerment (ACHIEVE) were published in 2009. Jeff Walline, OD and his colleagues designed this study to find out the effects that glasses and contacts had on the self-perception of the child. This study examined 484 myopic children 8-11 years. The participants were randomized to spectacles (n=237) or contact lenses (n=247) and followed for three years. The children were evaluated at baseline, 1 month and every 6 months for three years by a validated psychology tool for self-perception referred to as the Self-Perception Profile for Children (SPPC). The SPPC instrument allows a 4 point self-assessment in 6 categories; scholastic competence, social acceptance, athletic competence, physical appearance, behavioral conduct and global self-worth. The participants revealed the most dramatic areas of improvement with contact lenses compared to spectacles in the areas of physical appearance, athletic competence, scholastic competence and social acceptance. Similar to the low occurrence of adverse events with contact lens wear found in the CLIP study, over the three year period there were only 13 adverse events among 9 subjects. In addition, the ACHIEVE study found very similar rates of myopic progression in both groups of patients over the three year period (1.08D spectacle group and 1.27D contact lens group).
What can we conclude from these two studies?

One is that we are in a position to not only help a young person see but we are also in a position to do it safely and assist the child by instilling more confidence in themselves at a young age that may impact them as they mature into an adult who feels good about themselves. Young children are accustomed to following rules. When properly trained, these same young patients may grow into some of the most compliant patients that we have in our practice. There are some practical considerations for prescribing contact lenses to the younger patient. Mary Lou French, O.D. has stated the three M’s are important for success; Maturity (good hygiene, good communication skills, signs of responsibility), Motivation (why do they want contacts? Does the child want them or just the mom or dad? Are they active in activities where freedom from spectacles is important?), Mom (is the mom / dad / older sibling willing to help?). Don’t let age be the deciding factor. Consider your position as one that may positively impact the young patient in how they “see” and feel about themselves.

Buddy Russell - pediatric contact lensesBuddy Russell, FCLSA, COMT
Associate, Specialty Contact Lens Service
Emory University Eye Center