Myopia is a vision disorder that causes difficulty in seeing objects from afar, causing blurred vision. This change occurs when the eye is larger than normal, causing an error in the refraction of the image captured by the eye, that is, the image formed becomes blurred.
Myopia has a hereditary character and, in general, the degree increases until it stabilizes around the age of 30, regardless of the use of glasses or contact lenses, which only correct blurred vision and do not cure myopia.
Myopia is curable, in most cases, through laser surgery that can correct the degree completely, but the main objective of this procedure is to reduce the dependence on correction, either with glasses or contact lenses.
Myopia and astigmatism are diseases that can be present in the same patient, and can be corrected together, with special lenses for these cases, either in glasses or contact lenses. Unlike myopia, astigmatism is caused by an irregular corneal surface, which generates irregular images. Understand better in: Astigmatism.
How to identify
The first symptoms of myopia usually appear between the ages of 8 and 12, and can get worse during adolescence, when the body grows faster. The main signs and symptoms include:
- Not being able to see very far; Frequent headache; Constant pain in the eyes; Half-close the eyes to try to see more clearly; Write with your face too close to the table; Difficulty in school to read on the board; Do not see the road signs by far; Excessive tiredness after driving, reading or doing a sport, for example.
In the presence of these symptoms, it is important to consult with an ophthalmologist for a detailed assessment and to detect which alteration in vision impairs the ability to see. Check out the differences between the main vision problems in Differences between myopia, hyperopia and astigmatism.
Myopia degrees
Myopia is differentiated in degrees, measured in diopters, which assess the difficulty that the person has to see from afar. Thus, the higher the degree, the greater the visual difficulty encountered.
When it is up to 3 degrees, myopia is considered mild, when it is between 3 and 6 degrees, it is considered moderate, but when it is above 6 degrees, it is a severe myopia.
What are the causes
Myopia happens when the eye is larger than it should be, which causes a defect in the convergence of the light rays, since the images end up being projected in front of the retina, instead of on the retina itself.
Thus, distant objects end up being blurred, while nearby objects appear normal. Myopia can be classified according to the following types:
- Axial myopia: arises when the eyeball is more elongated, with a longer than normal length. It usually causes high-grade myopia; Curvature myopia: it is the most frequent, and occurs due to increased corneal or lens curvature, which generates images of objects before the correct location on the retina; Congenital myopia: occurs when the child is born with ocular changes, causing a high degree of myopia that remains for life; secondary myopia: it can be associated with other defects, such as nuclear cataract, which causes the degeneration of the lens, after trauma or surgery for glaucoma, for example.
Already when the eye is smaller than normal, there may be another disturbance of vision, called Hyperopia, in which images are formed after the retina. Understand how it appears and how to treat hyperopia.
Myopia in children
Myopia in young children, under 8 years old, can be difficult to discover because they do not complain, since it is the only way to see that they know and, moreover, their "world" is mainly up close. Therefore, children should go to a routine appointment at the ophthalmologist, at least, before starting preschool, especially when parents also have myopia.
How the treatment is done
The treatment for myopia can be done with the use of glasses or contact lenses that help to focus the rays of light, placing the image on the retina of the eye.
However, another option is surgery for myopia, which can usually be done when the degree is stabilized and the patient is over 21 years old. The surgery uses a laser capable of molding the natural lens of the eye so that it focuses the images in the correct place, reducing the need for the patient to wear glasses.
See more useful information about myopia surgery.
