Myopia: etiology, classification, risk factors, investigation and management

Myopia, also known as nearsightedness, is a common vision condition in which objects that are far away appear blurry, while objects that are close up are clearer. Myopia occurs when the eye is too long or the curvature of the cornea (the clear front part of the eye) is too steep, which causes light rays to focus incorrectly on the retina (the light-sensitive layer at the back of the eye). This results in blurry vision for distant objects.

Myopia is a common condition that affects people of all ages and is usually inherited. It is more common in people who spend a lot of time reading, working on a computer, or engaging in other close-up activities. It is also more common in people who have a family history of myopia.

Symptoms of myopia typically include difficulty seeing objects in the distance, such as road signs or the blackboard in a classroom, and the need to squint or strain the eyes to see clearly. Some people with myopia may also experience headaches, eye fatigue, or eye strain when trying to focus on distant objects.

Myopia can be diagnosed through a comprehensive eye exam, which includes a series of tests to assess visual acuity, eye health, and the curvature of the cornea. An optometrist or ophthalmologist will use a series of charts with letters, numbers, or symbols of different sizes to determine how well a person can see at different distances. They may also use other diagnostic tools, such as a slit lamp or retinal camera, to examine the eye in more detail.

Myopia can be corrected with glasses, contact lenses, or refractive surgery. Glasses or contact lenses work by bending the light that enters the eye in a way that helps it focus correctly on the retina. Refractive surgery involves reshaping the cornea to improve its curvature and correct the focusing problem.

There are several types of refractive surgery available for myopia, including LASIK (laser-assisted in situ keratomileusis), PRK (photorefractive keratectomy), and SMILE (small incision lenticule extraction). These procedures use lasers to reshape the cornea and are usually performed on an outpatient basis. They are generally safe and effective, but they do carry some risks and are not suitable for everyone.

In conclusion, myopia is a common vision condition that affects millions of people around the world. It is caused by the eye being too long or the curvature of the cornea being too steep, which results in blurry vision for distant objects. Myopia can be corrected with glasses, contact lenses, or refractive surgery, and it is important to seek treatment to ensure that the condition does not worsen over time.





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