What term is used for nearsightedness resulting from elongation of the eye?

The term used for nearsightedness caused by the elongation of the eye is myopia. This condition occurs when the eyeball is longer than normal, causing light entering the eye to focus in front of the retina rather than directly on it. As a result, objects that are close can be seen clearly, while distant objects appear blurry.

Myopia is common and can be identified by symptoms such as difficulty seeing distant objects clearly. In addition to anatomical factors like the length of the eyeball, myopia can also be influenced by genetic factors and environmental components, such as prolonged near work.

In contrast, hyperopia, or farsightedness, occurs when the eyeball is too short, causing light to focus behind the retina. Astigmatism results from an irregular curvature of the cornea or lens, leading to distorted or blurred vision at any distance. Presbyopia, on the other hand, is an age-related condition characterized by a gradual loss of the eye's ability to focus on close objects due to the hardening of the lens.

Understanding these differences is crucial for effective diagnosis and management of refractive errors.