what is myopia? Causes, Symptoms and Treatment

The human eye has the power to concentrate on near or distant objects. Usually, this is accomplished by the eye lens curvature. If the eye lens curvature is smaller than normal, it will concentrate on distant objects. However, there are occasions when the near eyesight is sharp while the far vision is foggy. This medical condition is termed myopia. Myopia is also termed short-sightedness or nearsightedness.

Myopia

Quick Definition: Nearsightedness, often known as myopia, is a common eye ailment that makes it challenging to focus on distant things. Close objects, however, are likely to appear crystal clear. Myopia can be treated with laser surgery or corrective lenses like glasses or contacts.

Myopia means A frequent eye condition where one has a clear vision for nearby objects but a blurry vision for distant objects. Common names for this ailment include myopia and near- or short-sightedness.

As we know, the formation of images takes place in the retina of the eye. Myopia prevents the retina from being able to form a picture because light rays converge too rapidly in the eyes and are therefore concentrated before they can form the picture.

The illustration above demonstrates how the picture that should have formed on the retina is now forming before reaching it because the lens is too concave. Thus, myopia creates a hazy vision of distant things.

What Causes Myopia?

Numerous factors can contribute to myopia. Some of these causes include:

• Hereditary: Myopia is frequently inherited, passing from generation to generation.
• Elongation of the eyeballs or development of the corneas: The light rays are refracted when the cornea normal curvature bulges. In such circumstances, the picture is formed before the cornea. Thus, resulting in the formation of hazy pictures. 
• Diabetes: Myopia can develop in people with uncontrolled diabetes when blood sugar levels rise.
• Untreated Cataract: Myopia can develop due to an untreated cataract, as myopic changes are one of its visible symptoms. If the cataract is not treated promptly, it could further develop myopia.
• Excessive Convex Lens: A situation of nearsightedness or myopia can develop if the shape of the lens becomes excessively convex.
• Increase in eyeball depth: Myopia can be developed if the eyeball is extremely deep with the cornea and lens’s ability to concentrate light rays. Instead of focusing on the retina directly, the light rays concentrate at a location in front of the retina.

Types of Myopia

Simple Myopia: 

In cases of simple myopia, a person’s eye is essentially healthy; however, using glasses or a suitable power lens can readily fit the problem. In this way, you may resolve the eye’s vision issue.

High Myopia: 

High myopia is the most severe type of myopia. Myopia, if identified early on, becomes more severe with advancing years. High myopia increases the risk of glaucoma, cataracts, and other eye diseases.

Pathological Myopia: 

Pathological myopia is also called degenerative myopia. Neither glasses nor contact lenses can treat this. The retina will also experience problems with the eye, such as:

• Lattice degeneration is a thinning of the retina.
• Retinal atrophy, loss of functioning and wastage of parts of the retina.
• Forster-Fuchs’ spot is retinal scarring that can cause blind spots.

Myopia of this kind can result in blindness.

Myopia Symptoms

Myopia has a wide range of symptoms. Among them are:

• When a person has myopia, it makes it difficult for them to see the signs in the distance clearly (for example, road signs). Though, they would be capable of seeing nearby objects.
• Another sign of myopia is when a person feels worn out when driving or participating in sports.
• Eye strain is also a sign of myopia.
• Headache is one of the frequent symptoms of myopia.

Treatment of Myopia

There are various methods for treating myopia. Here are a few of the methods:

Contact Lenses and Eyeglasses:

The most popular myopia treatments are eyeglasses and contact lenses. An optometrist will place an order for custom-built lenses with the appropriate prescription. These lenses can be inserted into any glass frame and will rectify any vision problems.

Another option is wearing contact lenses, also known as clear discs, that rest on the eye’s surface. Contact lenses can be customised for various prescriptions, just like glasses.

Contact lenses are a common alternative for those who do not like how glasses appear or feel because they are much smaller and less noticeable. However, they must be routinely changed and cleaned.

Orthokeratology:

In orthokeratology, hard contact lenses are worn overnight to reshape or restructure the cornea. It works by shifting peripheral vision into myopic, dragging down the major cornea, enlarging the mid-peripheral cornea, and reducing the central corneal epithelium. The requirement for eyeglasses or contact lenses during the daytime decreases due to the rapid reduction or elimination of refractive errors. Researchers found that orthokeratology can prevent the growth of myopia just as well as atropine.

Myopia can be treated non-surgically with orthokeratology. People with minor myopia can benefit from this treatment. This procedure includes wearing numerous hard contact lenses.

Surgery:

There are two surgical possibilities. The first involves the insertion of a corrective lens, and the second involves laser therapy.

Laser surgery is when an eye surgeon modifies the cornea’s shape using a strong light beam. Images that were previously fuzzy should now be clear following laser surgery because it changes how the eye focuses light. The surgery requires about ten minutes of operation. Although this alternative can be costly, it is typically painless. Within a day or two, vision should be normal.

But occasional visual haze or dry eyes for a few weeks or months afterwards are common. It’s crucial to show up for follow-up sessions to ensure that the eyes recover properly after this treatment.

Other types of surgery might involve inserting a corrective lens into the eye, either in place of or in front of the patient’s natural lens. The most severe kinds of myopia require this type of surgery.

Formula of Myopia

The formula of myopia helps calculate the lens’s power needed to correct myopia. For this, the following calculation of the combined lens’s focal length is used:

1/f = 1/f1 +1/f2

Where,

f = effective focal length

f1 = focal length of the lens required

f2 = focal length of the human eye

Distinction Between Myopia and Hyperopia

Your distance and nearby eyesight must be clear for your vision to function properly. Myopia (nearsightedness) and hyperopia, myopia opposite (farsightedness), are both refractive illnesses linked to how light is projected into the eye.

Hyperopia

Hyperopia, myopia opposite, is the medical name for farsightedness. If you have farsightedness, you can see things clearly in the distance but find it difficult to read or focus on things up close. In cases of hyperopia, either the eyeball is too short, or the lens’ curvature is insufficient to allow for optimal object focus. Instead of focusing in front of the retina or exactly on its surface, the light will focus at a location beyond the retina. Resulting in blurred vision.

Myopia

The reverse of farsightedness is nearsightedness. It indicates that you have trouble seeing distant objects. It occurs when the eyeball is abnormally lengthy. Light cannot concentrate correctly via the lens and cornea since it is longer than usual. The light rays that enter your eye while you observe an item concentrate at a position in front of the retina rather than at the retina itself. Resulting in distant objects appearing blurrier than nearby ones.

Conclusion

Myopia typically does not result in any other health issues. Several treatments enable people to live their everyday lives without experiencing the condition’s complications.

Those with more severe myopia must inform their optometrist of eye-light changes. They can face new eye problems or lose their vision if they don’t receive treatment.

Frequently Asked Questions