As a colleague from Wisconsin noted in her practice’s blog recently, a comment I made to a reporter might be misconstrued as discouraging adults from undertaking amblyopia therapy. I’ve been at this game for a long time now, 35 years to be precise, and dealing with the media is always a double edged sword. So let’s review the hullabaloo.
Some chap seeking his 15 minutes of fame claimed that hair styles in which girls combed their hair over one eye might induce amblyopia, or “lazy eye”. Naturally that attracted some attention, because parents often admonish children to get their hair out of their face. When a reporter contacted me to see what I thought about this rather sensationalist warning issued about the potential damage caused by abberant hair styles, I told him that the notion was basically preposterous. It has no basis in vision science or in common sense, and here’s why.
There’s a fundamental difference between the ability to improve amblyopia once it has developed, and the ability to induce amblyopia once a visual system has matured. For the latter to occur, there has to be some steady source of uncompensated blur in one eye, at all distances, for all waking hours, over a considerable length of time. Hair-blyopia hardly fits the bill for several reasons. One is that the comb-it-over-one-eye-style doesn’t deprive the brain of input from one eye during all waking hours. I don’t have enough hair to try it but if you do, demonstrate it to yourself. If you comb your hair over one eye, there will be visual angles at which you still get input equally from both eyes, such as looking downward. Add to that the likelihood that at some point during the day, upon awakening or before bed, that your hair will be out of your eye. After all this is a fashion statement, and when in the privacy of your own home chances are your brain will tell you to knock it off.
This is quite different from the notion of adults being able to put in consistent effort to learn how to use an amblyopic eye more effectively. Or, as one of the world’s leading researchers on the topic noted in his award winning lecture at the American Academy of Optometry last year, it is indeed possible to teach old dogs new tricks. You can download the article here. Dr. Levi makes my point quite well. On page 828 he notes that clinicians are well aware that ambylyopia does not develop after age 6 to 8 years. This suggests that there is a “sensitive period” for the development of amblyopia. However a sensitive period for the development of amblyopia does not equate to a critical period for the treatment of amblyopia, as Dr. Levi explains.
This old dog has only one small bone to pick with Dr. Levi regarding his otherwise excellent article detailing perceptual learning and excitation/inhibition balance in amblyopia therapy. He notes (page 835) that the idea of using a computer game to enhance visual skills in amblyopia is far from new. He’s right about that, but for some reason chose not to cite any references supporting the use of computerized therapy in Optometry. My colleague, Dr. Jeffrey Cooper, wrote an article a few years ago detailing the use of computerized therapy for a variety of visual problems including amblyopia. Heck, 30 years ago I wrote and edited a series of papers on the use of computerized therapy for VT, and one of my favorite pieces in there was written by Dr. Bill Ludlam on computerized therapy for amblyopia. The bound volume is still available through OEPF.
So who can argue with the notion that any publicity that gets the public talking about amblyopia concerns is a good thing? Not me. In fact, I give Dr. Levi credit for packaging tried and true principles of optometric vision therapy that have been around for years into a research paradigm that supports its efficacy. Here is a nice resource that quotes me accurately on the subject, and includes an article by Dr. Martin Birnbaum and his Residents at the SUNY College of Optometry dating back to 1977 citing a number of case studies demonstrating that there is no proven upper age limit for the treatment of amblyopia. Dr. Levi’s gift is that with his impeccable research and didactic credentials he is making amblyopia therapy fun. You can view a YouTube clip showing his collaborations on “Lazy Eye Shooter”, and how he’s moving toward making amblyopia therapy a wholesome family game. On the one hand it would be nice for developmental and behavioral ODs to get a little more respect for our persistence in utilizing these valuable principles over the past 30 or 40 years. Our predecessors were incredible visionaries. On the other hand, let’s enjoy watching contemporary researchers remove the brakes on plasticity, congratulate them on their discoveries, and utilize their applications. After all, there’s no such thing as bad plasticity.