Contact lenses are visual aid devices placed on the outer surface of the cornea of the eyes.
Contact lenses are visual aid devices placed on the outer surface of the cornea of the eyes. It can correct vision problems, such as near-sightedness (myopia), far-sightedness (hypermetropia), astigmatism (irregularities in the shape of the cornea). They efficiently neutralize the refractive errors arising from the irregular curvatures of the cornea. For therapeutic and cosmetic reasons, contact lenses are now becoming a popular alternative to eyeglasses for people. Contact lenses can treat defects that could be only partially treated using eyeglasses. Flexible biocompatible materials, such as silicone and acrylic glass, is used in the lens to make them safe, affordable, and easy to use.
There are contact lenses that are meant for daily use and are safe to be used for around 8-10 hours. Contact lenses that are meant for one-time use can generally be worn up to 14-16 hours without any adverse effect. It is recommended to take off the contact lenses 1-2 hours before bedtime to rest the eyes. Contact lenses are designed for continual use and can be worn overnight or as per the doctor’s instructions.
What are the types of contact lenses?
Contact lenses are classified based on the following:
- Central function: Refractive error lenses, color correction lenses, cosmetic contact lenses, therapeutic scleral lenses, and soft lenses.
- Manufacturing material: Rigid, soft, and hybrid lenses.
- Wear routines: Daily wear, extended wear, and continuous wear.
- Replacement plan: Single-use and long-term use.
How to use contact lenses
Only United States Food and Drug Association (US FDA) approved contact lenses that are prescribed by an eye care professional should be used. These lenses are tested and safe to use medical devices. Before buying, check with the eye doctor to find out the appropriate type of lens for you. Contact lenses should be worn properly to avoid getting an eye infection.
The basic steps to insert and remove a contact lens are as follows:
- Hands must be cleaned with antibacterial soap and dried before touching the contact lens to avoid transmission of dirt and bacteria, which may irritate the eyes.
- The lens should be placed at the tip of the index finger with the concave side facing upward, forming a bowl shape.
- The middle finger is used to pull down the lower eyelid and lashes.
- The lens must be placed on the white part of the eye just above the pulled lower eyelid.
- The contact lens should then be pressed gently to make them stick to the surface of the eye.
- Adjust it to the right position by blinking. The lens finally sits over the iris (the colored disc below the cornea).
- The same steps are repeated while placing the lens in the other eye.
- The lens should be worn only for the period advised by the doctor.
- While removing the lens, the lower eyelid is pulled down using the middle finger. The lens is taken out by using the thumb and index finger.
- The lenses should be washed with a sterile solution recommended by the doctor. After removal, it should be stored in the contact lens case.
- Lenses are recommended to be worn only for a few hours the first time.
- In case of any injury or infection, patients are advised to seek immediate medical attention.
Care and maintenance of contact lenses
Proper care and maintenance are important to preserve the efficiency of the lens and prevent any injury to the eyes. Ways to care for and maintain contact lenses include:
- The contact lenses should only be touched with clean, disinfected hands before and after their use.
- Contact lenses should be cleaned only with appropriate lens solution because they are made of hydrophobic materials, such as silicone blends, hydrogels. They do not mix with water.
- If the eyes are dry, they must be lubricated with eye drops or ointments prescribed by the doctor to avoid any itchy or burning sensation.
- Nails must be trimmed and kept short to prevent damage to the lens.
- Regular follow-up care and eye exams with the ophthalmologist is advised.