EXCELerated Vision

MFBF treatment for amblyopia shows patching alone is not enough

MFBF is a technique we use to accelerate vision development through office-based treatment of our patients with amblyopia. This latest research (October 2010), from Current Biology, shows that this MFBF(monocular fixations in a binocular field) treatment methods are evidenced based in Neuroscience. Read more in this interesting VisionHelp Blog post written by Dr. Leonard Press.

Research Support for MFBF Amblyopia Optometric Vision Therapy

The significance of this research is that occlusion therapy (eye patching) the "good eye", when utilized as the sole treatment, does not address critical aspects of binocular vision development for patients with amblyopia.

Dr. Fortenbacher has previously blogged on this topic and explains why eye patching alone is not enough to treat amblyopia. Parents need to be aware of this advancement in amblyopia treatment which is based on solid research. If you have a child who has amblyopia and the only treatment recommended is an eye patch, consider finding a doctor who will provide office-based vision therapy and the MFBF technique.   

Read Dr. Fortenbacher's previous VisionHelp post here: Amblyopia treatment – Eye patching alone is no longer the standard of care

Amblyopia treatment – Eye patching alone is no longer the standard of care

Amblyopia, other wise known as "lazy eye",  is the most common cause of preventable blindness in children. While the loss of vision usually occurs in one eye, rarer forms of bilateral amblyopia do exist. This type of  "blindness" occurs in approximately 2 out of 100 healthy children.   In amblyopia the loss of vision is not from a disease of the eye but rather the lack of development of the visual brain. Therefore, by definition, a child with amblyopia has healthy eyes, yet the brain can not see.

Therefore, the cause of amblyopia is not due to a disease process. Instead the cause of amblyopia is when there is interference in the infant's binocular visual development.  This means that amblyopia occurs when the visual brain of the baby stops developing normally from the lack of proper "two-eyed" visual input.  As a result, even with healthy eye structure, the child is not able to see clearly from the affected eye.  So, a child with amblyopia will typically have 20/20 eye sight in one eye and the other eye will be poor.  The severity of the amblyopia will be measured by how poor the eye sight is in the affected eye. In addition to poor sight, the child with amblyopia will also have "stereo blindness" or poor depth perception. This only adds to the visual difficulty since the child who is "stereo blind" will not be able to experience the benefits of three dimensional vision.

There can be many causes for amblyopia. But, the underlying mechanism for amblyopia is when something prevents a developing child from seeing with both eyes simultaneously. The most common causes are strabismus (eye teaming failure, such as crossed eyes) and unequal refractive error (example: high farsightedness in one eye while the other eye is normal). 

Debunking old myths and practices:

Over the years amblyopia was thought to be only treatable if caught before age 6. This myth has been disproven. Current research shows that amblyopia can be treated even in 18 year olds. More research needs to be done, but what we know is that there is "plasticity" in the human visual brain at nearly any age. I have personally successfully treated amblyopes well into their 60's.

A commonly prescribed form of treatment for  amblyopia, yet insufficient by today's standards (based on Clinical Practice Guidelines), is what is called "occlusion therapy". Occlusion therapy or "patching" is where the patient wears an eye patch on the "good eye" for typically hours at a time during their waking hours. While the research shows that a child's visual brain will show improvement in their amblyopic eye sight with a patching regimen, this "old school" approach (when used alone) can be very difficult and disruptive for the developing child to handle. It creates visual disorientation and confusion in spatial judgements. This in turn creates frustration and often emotional upset in the patient. Furthermore,  unilateral patching therapy only teaches a patient how to be a "one eyed person" since it does not address the underlying cause for the amblyopia which is the lack of  binocular (two-eyed) vision development. 

Therefore today's "best practices" approach for the treatment of amblyopia involves  a combination of monocular and binocular training of the visual brain through office-based vision therapy. This is done with a vision therapist  under the direct supervision of a Doctor of Optometry along with prescribed home-oriented visual activities to complement the weekly or bi-weekly in-office procedures.

This treatment approach yields the best outcomes, often resulting in normalization of eye sight in the amblyopic eye and the development of stereo vision (3-D vision) for the child. Eye patching alone is no longer the standard of care.

Read more about Amblyopia from the College of Optometrists in Vision Development (COVD). Click here!

Read about the Clinical Practice Guidelines established by the American Optometric Association. Click here!

Dan L. Fortenbacher, O.D., FCOVD

The Benefit of "Two-Eyed" Vision...The Ability to See 3-D!

A common question asked by parents of children with strabismus ("crossed-eyes") is, "What is my child seeing?"

My answer is, "It is not what they are seeing, it is what they are not seeing".

What the child with a crossed eye is not seeing is 3-D or stereo vision. In other words they are missing out on a quality of vision experience that is often difficult to put into words, but, in general means the ability to see the volume of space that exists between objects in our environment.

Surgery to correct crossed eyes may offer a cosmetic solution to crossed eyes, but surgery alone does not automatically provide the patient with stereo vision. However, office-based vision therapy is an effective treatment to not only help the patient acquire straight eyes, but also develop the brain's to gain the ability to see...3D!

Recently, Joe Palca (childhood photo above) columinist of National Public Radio, covered this in more detail with a personal perspective. Click here to read the article and even better to hear the audio story!

Dan L. Fortenbacher, O.D., FCOVD

Vision Therapy for Amblyopia...Building a house with more than just a hammer

Lazy eye or amblyopia, is the #1 cause of preventable and reversible blindness in children. Amblyopia can be caused by a variety of eye conditions, but the most common reasons why a child develops amblyopia is due to eye teaming failure (strabismus) or significant unequal refractive error between the two eyes. In either case, the reason behind the cause of amblyopia is due to an interference with the vision from each eye reaching the brain. Since humans are not born with 20/20 acuity, good vision must gradually develop naturally during infancy and toddler-hood. However, if something gets in the way of that normal sight development, then the result can be poor vision in one eye...amblyopia.

One interesting fact is that amblyopia is a diagnosis that is universally understood among eye care professionals as a condition that responds to vision therapy. The most common form of vision therapy for amblyopia is patching or occlusion therapy. Yes, patching therapy is an example of a "passive" form of vision therapy! The rational behind using occlusion therapy is that by patching the "good eye" you "force" the amblyopic eye to begin to do the work of seeing. So, occlusion therapy is the most universally accepted form of vision therapy in the eye care community. However, patching has many limitations as a stand alone treatment.

Patching can be accomplished with using a "black patch" to occlude the "good" eye or it can be in the form of a bandage that tapes over the good eye so that the child can not peek around the eye-wear frame. Patching can also be done pharmacologically, ie with a special eye drop called Atropine that will temporarily prevent the good eye from focusing by interfering with the focusing muscle of the eye.

But, it is important to know that "stand alone" occlusion therapy can bring about other signficant problems. First it is important to understand that when you cover up one eye in a child who does not see clearly in the other eye, that alone is very disruptive to that child's spatial orientation, motor development and coordination. To find out for your self put on someone else's glasses that results in you experiencing blurred vision and then cover one eye and walk around your house. How does that feel? Now imagine you are a young child and just learning how to coordinate you body and learn in the classroom and now you must wear a cover on your good eye. Do you think you would be very happy?

The second problem with patching is that it reinforces the child to be a one-eyed person. In other words, occlusion therapy does not teach a patient with strabismus how to see with two eyes since it reinforces the use of only one eye.

Third, using patching therapy alone is the equivalent of having only 1 tool in a tool box to build a house.

For example, if you set out to build a house and the only tool you had in your tool box was a hammer, then you most likely would only be able to hit nails. What type of house would you be able to build with just a hammer and nails?? A house that was not very well built or functional.

The same is true in when working with a patient with amblyopia. While occlusion therapy has been prescribed by optometrists and ophthalmologists for over 100 years in the treatment and management of amblyopia, as a stand alone treatment it often leaves the patient with an incompletely developed visual system where there is a lack of "two-eyed" vision and poor or no depth perception.

While there is a place for occlusion in the treatment of amblyopia, it is a passive form of treatment and it must be judiciously prescribed and monitored. But, most importantly, the child with amblyopia represents a patient with a complex binocular vision problem that requires more than the limitations of patching the "good eye"!

Active office based vision therapy guided by the doctor and vision therapist (in conjunction with appropriate lenses, prisms and when appropriate occlusion) is the proven treatment for children with amblyopia in the 21st century. Active vision therapy builds binocular vision, depth perception and function of the visual system. This is the "glue" to maintain your child's vision after treatment.

If your child has been diagnosed with amblyopia don't settle for a treatment plan that involves just an eye patch, just like you would not expect the builder of your home to have only a hammer as the only tool in his tool box.

Your child's doctor may begin with the judicious application of occlusion treatment as a starting point, for possibly a couple hours per day for a few weeks and monitor your child's progress. It will also be important for you to ask your doctor if he or she doesn't mention it in the beginning, who they would recommend your child to see for vision therapy to help with development of their binocular vision. It could make a difference that will affect their entire life.

Good binocular vision (with depth perception) means success for the patient recovering from amblyopia. That is what active vision therapy brings to child with amblyopia. A whole toolbox full of tools to build a complete and functional "visual home".

Dan L. Fortenbacher, O.D.,FCOVD