We have already covered most of the common ocular disorders in isolation and with regard to the specific eye structures affected. Nonetheless, we feel we should explain a bit more about amblyopia now.
What is amblyopia then and why does it come to be?
Although the exact mechanism of amblyopia development remains obscure…
In short, as you probably know so far, it is a disorder that ensues as the result of inappropriate vision development during early years of one’s life. As such, and by definition, it is characterised as decreased visual function without any noticeable pathologies. As simple and as alluring as this definition might sound, is it really true? Well, to a certain extent it is. People generally like to think that we comprehensively understand everything, being the big bang, the theory of relativity, the world’s economy, the action of certain medications and so on and so forth.
The truth is though, that we do not. The best we can do is to assume to a certain degree of confidence how particular things might be. Which, in reality, is totally fine and until someone comes up with a better explanation, perfectly adequate. Something similar applies to amblyopia as well. While it may be true that with all the available examination tools we have got, we do not find anything that could explain decreased vision in amblyopia, it does not mean that there is nothing wrong. Much out there is still beyond our current understanding, and exact pathophysiology of amblyopia is no exception. Whereas we do know that there is something wrong with the brain in amblyopia, we do not know exactly what it is. For that reason, as of today, we are still unable to address amblyopia more directly, more effectively if you wish.
… we can still treat it effectively!
Nonetheless, it is not all bad though. As long as amblyopia is treated early in its course, it is indeed one of the easiest and most effectively treated conditions we can treat. There is however, plenty of research which prove that amblyopia might actually be treated even better and more importantly, at much older ages. For now, all that remains experimental in animal models, but there is certainly hope that we will get some of it into clinical practice in the next few decades. We shall cover it briefly in the next blog!
Back to amblyopia now, why does it come to be then? In a nutshell, there is an imbalanced input from the two eyes in one’s early life. In other words, the image that one retina gets is much clearer than the image the other retina gets. As a consequence, the brain prefers the higher quality image from one retina (one eye). Therefore, the input from the worse eye is attenuated in the brain, which is why that eye becomes amblyopic.
We will go into further details still on that in the next blog. The conditions that can lead to the development of amblyopia are (a) deprivation, most commonly congenital cataract; (b) strabismus or squint and (c) unequal refractive power of the two eyes, which is called anisometropia.
Amblyopia treatment is then usually divided into (a) treatment of the cause and (b) treatment of the amblyopia itself. Treatment of the cause depends on the cause. It can either be cataract extraction for congenital cataract, correctly prescribed refractive correction for anisometropia, or surgery/prisms for strabismus. Treatment of the amblyopia itself on the other hand involves patching or various vision therapies such as our Amblyoplay.
In the next blog we will go into further neurophysiological details of amblyopia and will cover the potential mechanisms of how amblyopia could be treated pharmacologically. Stay tuned!