Myopia

Myopia or Nearsightedness is the condition of the eyes when a person sees clearly at a near distance, and at a far distance, everything is blurry. Myopia is also called a spasm of accommodation, that is, a spasm of refocusing. Usually, with myopia, the oblique muscles of the eyes are overstrained, and spasmodic and cannot unclench and refocus into the distance. Eyeball with myopia a little squeezed and extended forward. With nearsightedness -3 eyeball extended forward on 1 mm. With -6 on 2 mm.
At the same time, the straight rectus muscles of the eyes are weak and not trained and cannot contract and pull the eye back to the shape of a ball, even if the brain sends signals to do this.