Lenses that are produced as an alternative to glasses and attached to the front surface of the cornea to correct the refractive errors of the eye are called contact lenses. Contact lenses are a kind of prosthesis used for optical purposes as well as for cosmetic and therapeutic purposes. Contact lenses are lenses that are placed on the corneal surface and used for the correction of eye defects or for the treatment of certain diseases.
How Should Contact Lens Application Be?
A complete eye exam is required before contact lenses are prescribed. The most suitable contact lens for the eye is decided after the discussion between the patient and the doctor. With these evaluations, it is determined whether the eye is suitable for contact lens use. It is also decided what kind of contact lens you can use.
Adaptation is achieved by increasing the contact lens wearing time a little more each day. This adaptation period may be 3-4 days for soft lenses and 2-4 weeks for hard lenses. During the adaptation period, complaints such as watering, blinking, light sensitivity and redness may occur. These symptoms are usually temporary, otherwise the doctor should be notified.
What are the Contact Lens Types?
Contact lenses are generally divided into two categories as soft and gas permeable hard lenses. These are gas permeable hard lenses and soft lenses. Soft lenses are mostly used, except in a few situations where the use of gas-permeable hard lenses is required.
Soft (hydrogel) Lenses
Newly developed soft contact lenses can correct all kinds of visual impairments such as hyperopia, myopia, astigmatism, presbyopia (close reading difficulty). Soft Contact lenses, which are made of a hydrophilic material that can hold water, are very thin and bendable. It completely covers the cornea and overflows into the white sclera layer. There are different types. 1 day-lasting lenses used daily, 1-month-lasting lenses used daily, 3-month-lasting lenses used daily, 1-year-lasting lenses used daily, 1-week-lasting lenses used for 1 week, 1-month-lasting lenses used for 1 month, used for the treatment of some eye diseases such as therapeutic lenses, bifocal lenses and colored lenses.
hard contact lenses
It is used in all kinds of eye disorders where soft lenses are used. It is used especially in people with high and irregular astigmatism, whose vision is not good with glasses due to the irregular corneal structure called keratoconus. They get this name because they allow the passage of oxygen to the eye, and due to these features, they disrupt the corneal epithelial metabolism less. Since they do not take the shape of the cornea, they are especially preferred in cases such as high astigmatism and keratoconus.
Colored Lenses
A group of lenses that are very popular today are colored lenses. These lenses, which are applied by those who want to change their eye color, are also available in varieties that correct visual impairment.
Apart from these, lenses have been developed for people who have to use two separate glasses for near and far. These are called Bifocal Lenses.