Refractive Errors – Astigmatism, Myopia, Hyperopia

What Is Astigmatism? What Are Its Clinical Signs and Treatment Methods?

The transparent layer at the very front of the eye is the cornea. The cornea should normally be round with all its diameters equal; astigmatism occurs when, often due to heredity, the cornea is shaped like an egg with unequal diameters, so it refracts light with different strengths and forms two images on the retina.

Astigmatism present from birth may partially decrease until the age of 3, but after age 3 it continues unchanged. People with astigmatism see both distant and near objects blurred, and the shapes they look at appear stretched and scattered at the edges. There may be noticeable complaints of pain around the eyes and headaches due to the refractive error. Wearing glasses does not affect the degree of astigmatism. It does not cause it to progress or regress. However, it significantly improves the quality of vision. Apart from glasses, improvement can be achieved with contact lenses and laser (LASIK) treatments. For those who are not suitable for LASIK, LASEK surgery can be performed. An excimer laser is used in LASIK and LASEK surgery. The Wavefront method, known as “eagle eye,” gives the best results. After laser treatment, 90% of patients can see perfectly without glasses or contact lenses.

Cataract and Astigmatism

Cataract in patients with astigmatism can be corrected surgically at the same time. To correct astigmatism in a patient with cataract, an intraocular lens or corneal incisions, known as a toric lens, can be applied. At İzmir Özel Can and Salihli Özel Can Hastanesi, our specialist ophthalmologists are highly competent in the treatment of astigmatism. Please call us for an appointment and information.

Myopia (Nearsightedness)

Because the eye is longer than normal, people with myopia see distant objects blurred and near objects clearly. They often squint to see distant objects. This can cause severe headaches.

Myopia can be classified as mild (below 3 diopters), moderate (3–6 diopters) and high myopia (above 6 diopters) . The degree of nearsightedness can increase until the age of 18. However, with intensive reading, screen use and mobile phone use, the increase may continue after the age of 18.

Wearing glasses does not reduce the degree of myopia but improves image quality. Apart from glasses and contact lenses, other treatment approaches are laser and intraocular lens procedures.

Hyperopia (Farsightedness)

Because the front-to-back diameter of the eye is shorter, people with hyperopia see distant objects clearly and near objects quite blurred. However, toward the age of forty, the higher the degree of hyperopia, the more distance vision may also deteriorate. Hyperopia is common in babies; as they grow and the eye lengthens, a decrease in the degree of hyperopia may be observed until the age of 18. However, after the age of 18 there is no significant change. After the age of 40, glasses may also be needed for distance vision. Using glasses and contact lenses does not reduce the degree of hyperopia but improves visual acuity and quality of vision. In patients who do not want to use glasses or contact lenses, the success rate of laser surgery is 90%.

Presbyopia

As the lens inside the eye loses its flexibility with age, near vision deteriorates, particularly after the age of 40, and the need for glasses arises. However, in some people, myopia develops with advancing age as a result of cataract formation, and the need for reading glasses may disappear. In this case, however, their distance vision has deteriorated.

The simplest solution in the treatment of presbyopia is reading glasses. However, presbyopia can also be corrected with laser surgery. Among the surgical methods;

Monovision Surgery: In people with impaired near vision, when one eye is made slightly myopic, the need for reading glasses can be minimized.

Trifocal Multifocal (Smart Lens) Implantation: While multifocal lenses are set for near and far distances, trifocal lenses, known as smart lenses, provide excellent quality vision not only at near and far but also especially at intermediate distances ranging from 40 to 80 cm. They are extremely useful, particularly for people who use computers, watch television from a short distance or work at kitchen counters.

They are preferred in cataract surgery or for correcting high prescriptions that are not suitable for laser treatment. The surgery takes 5–10 minutes per eye. The patient can have clear vision the next day. However, it is recommended to avoid strenuous activities for 15–20 days.