Amblyopia’s personal story and how the latest research is shaping a path for better results in patient care

It’s especially important to you If you have a child or grandchild diagnosed with it. It’s important to you if you, yourself have grown up with it. It is important to you if now you have to live with it. And certainly when given a choice you want the best medical treatment for it. However, if you are like most who have lived with it you have probably experienced the most common approach in treating it.  A treatment that has been around for nearly 300 years and has stood the scrutiny of clinical research as being effective at improving it in patients who comply with treatment before age 10,  albeit with the many negative side effects and often limited results. Therefore, “it” can become personal.

What is it? Dr. Press and I have written several posts on the VisionHelp blog that expands on this topic.  Why? Because it is a serious vision problem, the number one cause of preventable and potentially reversible unilateral blindness in children and affects over 10,000,000 children and adults in the US, 2-4% worldwide. It’s name most commonly comes with a pejorative associated with being lazy.  The “it”, typically referred to as “Lazy Eye“,  but correctly known as  Amblyopia, is the only medical condition that has “lazy” associated with a health problem and yet there is nothing lazy about “it”!

While Amblyopia’s cause is  fully researched and understood as a disruption in binocular vision at an early age,  the current standard of care involves a monocular form of treatment called occlusion/patching therapy. Additionally there has been a surge of new research that shows Amblyopia to be far more complex than just diminished sight in one eye. Furthermore, the latest research shows that there is a superior way to treat  Amblyopia  that is faster, has better results, and without the negative associations compared to patching. In turn, this has the potential to establish a new standard for Amblyopia treatment that will result in improved patient outcomes without the untoward  side effects of occlusion and not limited by age. Yes, even adults can be successfully treated!

Therefore , the reason for this latest “chapter” on the topic of Amblyopia is because now we will begin to take a look at some of the latest research that exposes Amblyopia to be far more complex than just diminished sight in one eye. There are many parts to the Amblyopia puzzle, that when better understood, help to identify how to more effectively treat the condition than ever before.

But, before we delve into the details of research let’s begin with a true story about one of my patients, a child with Amblyopia who for the sake of this post, I’ve changed his name to James.

At the time when I first saw James he was almost 7 years old.  His parents brought him to my office as a referral from his occupational therapist who had concerns about his paper pencil abilities  and other fine and gross motor skills.  James had been originally diagnosed by his previous eye doctor with Amblyopia of his left eye with a best corrected visual acuity of 20/100. His right eye could see 20/20. The cause of James’s Amblyopia was due to an unequal refractive condition (Anisometropa – left eye significantly more farsighted compared to his right eye).  James’s eye doctor started James on the standard approach for amblyopia by prescribing him glasses and then patching of the right eye plus atropine drops. This went on for one year! However, in spite of his parents effort to comply with the “gold standard” occlusion treatment, his best corrected visual acuity in his left eye remained with a severe form of Amblyopia…20/100!

But the impact of Amblyopia was much more than a loss of visual acuity for James’s life. Like most  patients with Amblyopia, James’ visual problems were far more complex than the loss of visual acuity in his one eye. James had trouble with his handwriting,  writing uphill and downhill. He had trouble with  catching or hitting a ball. He had trouble with his gross motor skills, seemed clumsy and even had trouble riding his bike. While he was a capable reader, when presented one word at a time,  James relied on using his finger and lost his place easier than normal for his age. But, equally significant, James presented with a history of frustration involving emotional outbursts. His parents expressed a major concern that James may have an “emotional disorder”.

James’s comprehensive visual assessment found not only did he have poor visual acuity in his left eye (20/100), but he had problems in visual-motor skills, visual spatial judgment, suppression of the left eye,  no depth perception, poor micro eye movement  and problems with visual perception.

So now let’s take a look at what the current research shows. Not just any research, but research of the highest caliber of scientific evidence, published in prestigious ophthalmological medical journals called a “systematic review”. In the evidence pyramid, a systematic review  is considered superior even to a randomized clinical trial. One systematic review evaluated Amblyopia’s Impact on Quality of Life in 2010 by  the Health Economics and Decision Science (HEDS), School of Health and Related Research and published in the prominent  Eye Journal in 2011.

What the researchers found was that the implications of Amblyopia and/or it’s standard methods of treatment fell into four broad categories:

Impact on Family Life, Social interactions, Activities, Feelings and Behaviors

Family Life– standard amblyopia occlusion therapy resulted in:

• Increased stress and anxiety for the parent
• Negatively impacted care giver-child relationships
• Other relationships within family also affected
  • Siblings teased or bullied the child in treatment
  • The increase in parent attention associated with the treatment

Social Interactions-standard amblyopia occlusion therapy resulted in:

• Bullying and interactions with peers is widely documented as a result of the treatment
• Feelings of isolation and noting differences between others were also documented

Activities:

• Frequently reported implications was the impact of amblyopia on career choice and educational attainment
• Immediate impact on school activities during standard treatment (occlusion while at school)
• Long term impact on adulthood career choices
• Impact on daily living activities was well documented

Feelings and Behaviors- standard amblyopia occlusion therapy resulted in:

• Feelings of low self-esteem and negative self-image commonly reported due to amblyopia alone or due to its treatment
• Depression
• Frustration
• Embarrassment

Moving beyond occlusion treatment to the actual complexities of visual problems associated with Amblyopia, in another research review researchers evaluated eye-hand coordination, walking, driving, and reading skills of children and adults with amblyopia entitled: Amblyopia and Real-World Visuomotor Tasks. Published in ophthalmology’s , S Grant, MJ Moseley. Strabismus, 2011; 19(3) 119-129, the following was concluded: “Amblyopes show a range of visuomotor impairments with the affected eye alone, but also in the binocular mode the amblyope is also slower and less accurate than normally sighted individuals.”

The following specific areas were reviewed along with the researchers conclusions:

Amblyopia and  Eye Hand Coordination:

• Amblyopic individuals, children and adults have significant deficits in movement, speed and accuracy
• Those who completed occlusion therapy in childhood with normalized “cured” visual acuity in their amblyopic eye but had reduced stereo acuity (100-3000 arc secs) had significantly more spatial errors and eye-hand coordination vs controls

Amblyopia and Walking

• While walking speed and gait are not affected by amblyopia, studies show stereo deficient amblyopes were more prone to trip when in obstacle-loaded environments
• Driving:  Stereo deficient amblyopes showed to be less prone to road traffic accidents due to earlier braking tendencies. However when stereo deficient subjects were engaged in driving in and around obstacles there was an increase risk of colliding with barriers

Amblyopia and Reading

• Deficits in micro eye movements contribute to reduced reading speed associated with central or total suppression of the amblyopic eye compared to the normal control subjects
• These deficiencies were apparent even when monocular testing with the non-amblyopic eye compared to the non amblyopic controls

Returning to our story, indeed James’s examination findings were consistent with the new research on Amblyopia. That is the loss of vision from Amblyopia for James was more than reduced visual acuity. His loss of visual acuity was only the tip of the “visual-loss” iceberg.

Just as the research shows Amblyopia results in poor depth perception due to suppression of the amblyopic eye, poor eye hand coordination and spatial judgments, poor gross motor skills, deficient micro eye movement for reading fluency and emotional consequences and reduced self esteem. This in effect was our patient James!

Furthermore,  James’s lack of response to his previous one year of occlusion therapy and all of its negative side effects suggests that occlusion treatment ultimately failed to address the fundamental cause of his condition. Yes, occlusion treatment has a role in the advanced treatment of amblyopia, but only in very specific applications of activities that require minutes of time with measurable outcomes.  What the new research shows is that a more effective approach to treating Amblyopia should begin with binocular vision development therapy coupled with perceptual learning, eye hand coordination therapy, visual processing therapy and oculomotor therapy, particularly saccadic eye movement. (more on the specifics of this in the posts soon to follow)

Using this treatment model for James over the course of 4 months resulted in the following:

His left eye improved in best corrected visual acuity to 20/40, suppression was eliminated, his depth perception  became strong (stereopsis  40″),  his gross motor abilities were good and he learned how to ride his bike, his handwriting became legible and effective, his visual perceptual abilities and oculomotor skills also became age appropriate. Of equal importance, he became a happier child and no more abnormal emotional outbursts. That, in addition to all of his other gains, made his parents very happy!

In the next VisionHelp Blog posts on Amblyopia I will show the latest swell of new research in the area of binocular vision therapy and perceptual learning that has specifically shaped the path for this advanced evidenced-based model of treatment for Amblyopia. In the meantime, we can all help keep this message alive.

On this Memorial Day 2015 and beyond, let’s make this a time to end Amblyopia for those who unnecessarily struggle with “it”! Please share this post to those family and friends, parents and grandparents who may have a child or grandchild with Amblyopia.

Dan L. Fortenbacher, O.D., FCOVD