How is myopia corrected?
Myopia can be corrected by spectacle lenses or by contact lenses. Partial correction or control can also be achieved by drugs or surgery. (A) Spectacle lenses: Myopia is corrected by using minus or diverging lenses. Usually a full spectacle correction is givn for distance if the myopia is mild or moderate (upto 5 dioptres). Myopia of greater degree is always undercorrected. Various authorities now also advocate a much lower separate power for reading. This serves in controlling excessive progression of the power of myopia, specially in children. (B) Contact lenses: These have the advantage of normally maintaining the size of the object when viewed unlike spectacles which cause an apparent decrease in the size of the object. Contact lenses, in certain selected cases, certainly do seem to have an excellent capacity to control the myopia which otherwise may be progressing at a rapid pace. They do not seem to have much effect on degenerative or congenital myopia but are now recommended by
