Contact lenses: types, what you need to know and what is the best choice

Contact lenses discreetly to the people around you correct the vision of the person who wears them. Modern models of lenses are designed so that the eyes quickly get used to them. Mainly, contact lenses differ in optical power and type of material. This affects the duration of use of the products.

Types of contact lenses

Depending on the properties, contact lenses are used to correct various eye pathologies:

• spherical and aspherical eye lenses are prescribed for farsightedness and nearsightedness;
• Toric lenses are used to correct astigmatism, and they also correct myopia and hyperopia;
• Multifocal lenses are used to correct farsightedness in the elderly.

Contact lenses are differentiated by the property of the material. Soft lenses are the most popular. They are elastic and thinner. Soft lenses are faster to get used to because they don't feel as much. They are worn for a longer time during the day.

Hard lenses are used for keratitis, keratoconus and other specific pathologies. They are not plastic, do not pass oxygen in sufficient quantity, so they are worn for a limited time.

What soft contact lenses are made of:

• Hydrogel is a hypoallergenic material with a high moisture content. It is suitable for people with sensitive eyes.
• Silicone hydrogel - the material has a high permeability rate. It allows oxygen to pass through, so they can be worn longer. However, in some people, silicone hydrogel can cause allergies.

According to the duration of use, contact lenses come in several types:

• Day lenses are worn only during the day. At night they need to be removed.
• Lenses with flexible use can be left on overnight, but for no more than two nights.
• Contact lenses of prolonged mode can not be removed for six days. However, after use, they must be replaced with new products.
• Continuous wear lenses can not be removed for about a month around the clock.

Doctors do not recommend wearing long-use lenses often. They limit the flow of oxygen. Prolonged presence of a foreign object in the eye area can lead to additional vision abnormalities.

Contact lenses come in one-day contact lenses - you need to wear a new pair every day. Two-week lenses are replaced after the expiration date. There are lenses that can be used for a month or two.

How to choose contact lenses

Only a doctor can correctly choose the right contact lenses. He conducts an examination on special apparatuses, determines the type of vision pathology. The doctor evaluates the curvature of the cornea, intraocular pressure, the function of the eye muscles and the lateral vision. After the examination, the specialist will choose a suitable model of contact lenses and write a prescription.

It is important to keep in mind that the optical power of lenses differs from the characteristics of glasses. Therefore, it is not necessary to be guided by the dioptric value of glasses. The doctor will help you find the appropriate parameter of the optical power of lenses. It may be necessary to wear lenses with different dioptres in order to choose the one that gives the clearest vision.

Doctors recommend wearing lenses of short-term use. The optimal option is a two-week means of vision correction. Disposable contact lenses are suitable for use when traveling and when it is not possible to carry out the necessary hygiene for such products.

Classic vision correction lenses are transparent. There are models that change the shade of the eyes. They cost more. Colored lenses are chosen so that the shade fits individually.

You should not buy lenses on your own without a doctor's prescription. If you wear the right lenses, you can worsen the condition of your eyes. You should also follow the instructions that come with the vision correction product.