What is nearsightedness (myopia)?
Myopia is an eye disease in which a person cannot see objects at a far distance. A nearsighted person has no problems looking at near objects (reading, working at close distances), but distant objects lose their sharpness.
In myopia, the parallel light rays passing through the refractive media of the eye (cornea, lens, and vitreous body) are focused not on the retina but in front of it. As a result, the image appears blurred.
Myopia is one of the most common eye diseases in the world. About 15 million people in Ukraine suffer from different types of myopia.
Symptoms of myopia
In addition to the characteristic decrease in visual acuity, the following symptoms may indicate the disease’s progression:
- Headaches;
- Pain in the eye socket;
- Dryness and ocular pain;
- Flickering in front of the eyes;
- Impaired twilight vision, the so-called night blindness;
- Increased lacrimation.
What are the causes of myopia?
Myopia is caused by a mismatch between the strength of the optical system of the eye and its length. The main causes are:
- Irregular (elongated) shape of the eyeball. Normally, the anteroposterior axis of the eyeball in an adult is 24 mm. With myopia, it can be up to 30 mm.
- Increased refraction of light rays by the optical system of the eye – cornea or crystalline lens.
- Weak accommodation muscle that holds the lens in place. The lens, which is elastic and flexible, uses this muscle to bend and focus so that we can see clearly both close and far away. This is the so-called accommodation process. Overstretching the accommodation muscle results in poorer long-distance vision.
- Myopia (often found at school age) is caused by prolonged work at close distances: excessive use of computers and other gadgets, improper lighting, reading in transport, and so on.
Particular attention should be paid to children, as a child is often unable to clearly outline the problem. He/she may feel uncomfortable, irritable, and capricious. If your child often rubs his/her eyes, squints when looking at distant objects, tries to hold a book or notebook close to his/her eyes, it is worth visiting an ophthalmologist immediately!
Risks of myopia
In addition to poor vision in the daytime, myopic people have impaired twilight vision. At night they find it particularly difficult to navigate on the street, drive a car. With the constant strain on the eyes, myopic people have headaches, they quickly become fatigued. The most dangerous condition is retinal detachment, threatening the irreversible loss of vision.
Myopia grades
Depending on how much the visual acuity of a person suffering from myopia is reduced, ophthalmologists distinguish three degrees of this condition:
- Mild myopia up to 3D;
- Moderate myopia ranging from 3.25D to 6D;
- High myopia over 6D.
Myopia increases as the eyeball grows in length. Lengthening by 1 mm gives a decrease in visual acuity by 3D.
Mild myopia is characterized by an increase in the eye length of 1-1.5 mm. With such a refractive error, one sees the outlines of distant objects a little blurred.
Moderate myopia is characterized by elongation of the eyeball by 1-3 mm. At this stage, the membranes and vessels of the eye undergo changes, stretching, and thinning. Distance vision is reduced, while close vision is clear and distinct at a mere 20-30 cm.
High myopia is characterized by an increase in the eyeball length of 3 mm or more. This is likely to cause significant thinning of the retina and vascular membranes of the eye and a significant decrease in visual acuity up to 30D or more.
If not treated properly, vision deterioration can progress significantly and fairly quickly as the disease progresses.
Types of myopia
- Congenital
It is quite rare. In 2% of cases, a child is born with an enlarged eyeball relative to the norm. In the vast majority of cases, myopia occurs at school age.
- Hereditary
Defects in the synthesis of the connective tissue protein (collagen), which is essential for the sclera membrane, may be inherited. Weakening of the sclera tissue leads to an increase in the eyeball size and, consequently, to myopia. If both parents are nearsighted, the risk of myopia in a child is 80%; if one parent is nearsighted, it is 40%.
- Progressive
If the vision deteriorates by more than one diopter per year, it is progressive myopia that requires special attention and treatment. Myopia progresses most intensively in children during their school years when visual strain is particularly high.
Myopia can be true, i.e., caused by the specific eye structure, and pseudomyopia when vision is impaired due to accommodation disorders, while anatomical changes (lengthening of the eyeball) are not observed.
Myopia diagnosis
Eximer Ophthalmology Clinic performs a comprehensive diagnostic of the visual system to provide the most accurate diagnosis possible, including:
- Determining visual acuity;
- Measuring refraction (the ability of the optical system of the eye to refract light rays);
- Measuring intraocular pressure;
- Ultrasound examination of the internal structures of the eye (including in opaque media);
- Diagnosing internal abnormalities;
- Examining the shape and refracting power of the cornea;
- Studying the visual field;
- Studying the retina and optic nerve.
Such a complete assessment of the visual system is required to understand which treatment methods would be optimal in each separate case.
Ways to deal with myopia
Any type of myopia correction is aimed at weakening the refracting power of the eye so that the image hits the central area of the retina. Today, there are over 20 ways to correct myopia. The most common (and oldest) is eyeglasses. In recent decades, contact lenses are gaining popularity. However, these methods allow you to see well only for a while.
Pros of glasses and contact lenses
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Cons of glasses and contact lenses
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Glasses and contact lenses do not solve the myopia problem entirely, but rather involve certain difficulties and discomfort.
There is a solution!
For those who aren’t willing to put up with the restrictions associated with wearing glasses and contact lenses, there are modern ways to solve the problem. The most modern and common today is laser vision correction.
How do you deal with myopia?
Compare survey data from 2000 and 2015.
Survey results show that an increasing number of people prefer laser vision correction to get rid of myopia.
Myopia treatment at Eximer Ophthalmology Clinic
Eximer Ophthalmology Clinic offers the most up-to-date methods of myopia treatment. These methods are always chosen individually, based on a thorough diagnostic examination of the visual system, determined by the type of the disease and the degree of its development.
Laser vision correction
Laser vision correction is achieved by changing the shape of the cornea (the natural refractive lens of the eye) through laser exposure. During such correction, the cornea is shaped individually for each patient. Laser correction treats mild, moderate, and high myopia up to 12-15 diopters. Eximer Ophthalmology Clinic offers the most advanced methods of laser correction, including femtosecond laser vision correction and Custom Vue personalized correction with aberrometry analysis.
Phakic lens implantation
Phakic lens implantation is applied to treat high myopia (up to -25 diopters), in cases when the natural accommodation of the eye is still present. A special phakic lens (basically the equivalent of a contact lens) is implanted into the posterior or anterior chamber of the eye through a micro-access of 1.8 mm.
Refractive lens exchange (lensectomy)
Refractive lens exchange is used to treat high myopia (up to -20 D), in cases when it is inexpedient to perform laser correction or the natural ability of the crystalline lens to accommodation is lost. The procedure is based on the removal of a transparent crystalline lens and the simultaneous implantation of an artificial lens (intraocular lens) of the required optical power through a micro-access of 1.8 mm.
Orthokeratology
This is a non-surgical method of temporary myopia and astigmatism correction, otherwise known as corneal refractive therapy. Paragon overnight contact lenses provide temporary myopia relief by changing the shape (alignment) of the cornea. This method is most effective in children and young adults.
Scleroplasty
Surgical intervention is performed for progressive myopia. It is aimed at stopping the eyeball growth and slowing down the myopia progression. A special plate is inserted behind the back wall of the eye, which serves as a kind of sclera framework, thus strengthening the walls of the eye, stopping its growth and myopia progression.
Machine-assisted methods
Special machine-assisted therapy helps relieve myopia in childhood and in some cases even get rid of it altogether. A set of machine-assisted procedures is chosen individually for each child and the treatment results are closely monitored by the doctor.
The key point is to fail to neglect myopia! The doctors at Eximer Ophthalmology Clinic can provide you with an individualized, state-of-the-art treatment depending on your age, type and degree of the disease, and lifestyle.
Myopia and the retina
In many cases, myopia is caused by an increase in the size of the anteroposterior axis of the eyeball, which can lead to stretching of the retina. This is the thinnest layer of the eye, being light-sensitive. When stretched, the retina becomes thin, causing the risk of dystrophy, tears, and detachment. The higher the degree of myopia, the higher the probability of retinal disorders. To prevent these, Eximer Ophthalmology Clinic offers peripheral prophylactic laser coagulation of the retina.
Myopia and astigmatism
Myopia is often combined with another refractive problem called astigmatism. In astigmatism, the sphericity of the cornea (less often the lens) is disturbed. It has different curvatures in different directions. Correspondingly, the refracting power of the corneal surface varies in different meridians, and when light rays pass through such a cornea, the image is distorted.
Myopia combined with astigmatism can cause serious discomfort. Standard optical correction cannot provide optimal visual characteristics, and special spherical-cylindrical glasses or toric contact lenses are required. Laser vision correction is the best way out in this case.
Myopia prevention
If myopia is an anatomical feature, it cannot be prevented, but it is possible to avoid progression or significant deterioration of visual characteristics. Here are some recommendations.
- Have regular check-ups with your ophthalmologist, especially when the risk of myopia is high.
- Arrange proper lighting of the workplace.
- Observe the visual strain regimen, take breaks during long hours of work at the computer, reading, and other visual work.
- Visual exercises and special eye training help relieve the strain.
- Move more, walk outdoors.
- Watch your diet. You should eat protein, vitamins, and micronutrients such as Zn, Mn, Cu, Cr, and others.
