It is an alteration of vision due to the fact that the eye is larger than normal, which causes the image to form in front of the retina, reaching it blurred. Typically causes blurred distance vision with good near vision.

It can be mild-moderate myopia (up to 4-5 diopters) or high myopia (from 6 diopters).

The presence of a family history of myopia is a risk factor for having this ametropia, as is the fact of doing long hours of work closely or getting very close while writing.