Myopia is the medical term for nearsightedness, which is a vision condition whereby one can see near objects clearly, but further away objects appear blurry.
Causes
Myopia occurs if the eyeball is too long, or the cornea is too curved. As a result, the light entering the eye is not focused correctly, focusing in front of the retina, the light-sensitive part of your eye, instead of directly on the retina, resulting in distant objects looking blurry.
Myopia may be inherited, and thus if a parent has myopia, most likely their child may have it as well.
Environmental factors and other health problems may also cause myopia. Environmental risk factors include doing work that involves focusing on close objects or greater time spent indoors.
Symptoms of myopia may also be a sign of variations in blood sugar levels in people with diabetes or perhaps an early indication of a developing cataract.
Types of myopia
Mild myopia or low myopia is the most common form of myopia in an otherwise normal eye.
More severe myopia is known as high myopia and it will usually stabilise between the ages of 20-30 years old. High myopia can be corrected with glasses, contact lenses or refractive surgery.
Degenerative myopia, also known as pathological or malignant myopia, is a rare type of myopia usually genetically inherited. The eyeball gets longer very quickly and causes severe myopia, usually by the teenage or early adult years and can get worse far into adulthood.
Those with degenerative myopia may have a higher chance of having a detached retina, abnormal blood vessel growth in the eye and glaucoma.
Symptoms
The main noticeable symptom for myopia is the blurry far distance vision.
For children, behavioral symptoms include inability to focus in class due to having trouble reading the blackboard at school.
These symptoms may become more obvious when children are between ages 8 and 12 years old. — The Health