ivierre
Amblyopia is a condition where the affected eye cannot be corrected by prescription lenses, or otherwise.
I think (and I obviously will stand to be corrected by those who know for sure), that in undiagnosed, (and therefore, uncorrected) amblyopia in childhood, the neural pathways from the eye to the brain do not develop properly, so good vision is never attained in that eye.
If discovered in early childhood, methods such as surgery or eye patching are used to 'force' the brain to accept vision from the defective eye, thus preventing the deterioration in the neural pathways.