Amblyopia is usually caused by one of the following visual abnormalities, anisometropia, visual deprivation, or strabismus. Those were already thoroughly discussed in our previous posts, so follow the links above should you be interested. In the current blog, we will talk about a special form of strabismus referred to as microstrabismus or microtropia and its impact on vision and resulting amblyopia.
Microstrabismus is defined as the deviation of the eye less than 5° with the accompanied reduced or absent stereovision. Proper strabismus is usually evident with the naked eye and those kids are therefore soon referred to as an ophthalmologist for an evaluation. In microstrabismus, on the other hand, the eye deviation is usually very hard to spot and the condition often remains undiagnosed for a long time. Hence it is likely that amblyopia will commence in the ever so slightly deviating eye. Another problem that usually arises with amblyopia caused by microstrabismus is the lack of foveal fixation in the deviating eye – eccentric fixation. The image that falls onto the retina of the deviating eye is slightly offset which can make treatment challenging.
Treatment of amblyopia due to microstrabismus
Treatment of amblyopia induced by microstrabismus addresses several aspects, among which is the restoration of foveal fixation (directly in the fovea), stereovision, and normal visual acuity. These are usually achieved by a combination of patching, special exercises aimed to reduce eccentric fixation, as well as vision training in some instances.