Welcome to the world of convenience and freedom from the restrictions of spectacles. Now you can consider and enjoy a much wider range of fashionable sunglasses, without requiring prescription lenses and seeing well. Contact lenses are less affected by wet weather, don't steam up and provide a wider field of vision making them the best option for most sporting activities.
Some conditions such as keratoconus and aniseikonia are typically corrected better with contact lenses than with spectacles, yet the need for spectacle wear at times or over the contact lenses is commonly accepted to maintain eye health and optimal vision.
A rigid gas permeable lens (or RGP) lens is able to cover the natural shape of the cornea with a new refracting surface. This means that a spherical rigid contact lens can correct corneal astigmatism. Rigid lenses can also correct irregular corneas, such as those with keratoconus or post trauma. In most cases, these patients see better through rigid lenses than through glasses.
Modern lenses rely on their water content to transmit oxygen through the lens to the cornea. As a result, higher water content lenses allowed more oxygen pass through to the cornea. New manufacturing techniques and changes to multipurpose solutions have resulted in greater comfort to the wearer. Soft lenses can be further classified as:
Daily disposable contact lenses are discarded nightly and therefore require no care. Daily disposable contact lenses are single-use lenses that are removed and discarded at the end of each day, and a fresh pair of lenses is applied to the eyes the next morning. Daily contact lenses are gaining in popularity among practitioners and consumers for their health and convenience benefits.
These are lenses that are worn daily, but cleaned and stored at day end, then reused the following day. This procedure can be repeated either for a month, or bi weekly according to the manufacturers’ specifications. The cleaning and storing of the lenses needs to be done to a high level of cleanliness to avoid pathogen contamination, or physical damage
Monovision is a technique whereby single-vision lenses (one focal point per lens) are used to focus one eye (typically the dominant one) for distance vision and the other for near work. The brain then learns to use this setup to see clearly at all distances.
Multifocal contact lenses (e.g. bifocals or progressives) are comparable to spectacles with bifocals or progressive lenses because they have multiple focal points. Multifocal contact lenses are typically designed for constant viewing through the center of the lens.
Cosmetic contact lenses are designed to change the appearance of the eyes. These lenses may also correct refractive error. Although many brands of contact lenses are lightly tinted to make them easier to handle, cosmetic lenses worn to change eye color are far less common, accounting for only 3% of contact lens fits.
Soft lenses are often used in the treatment and management of non-refractive disorders of the eye. A bandage contact lens protects an injured or diseased cornea from the constant rubbing of blinking eyelids thereby allowing it to heal. They are used in the treatment of some pathological conditions.
Wearing and hygiene
Before touching the contact lens or the eye, it is important to wash hands thoroughly with soap and rinse well. Drying of hands using towels or tissues before handling contact lenses can transfer lint (fluff) to the hands and, subsequently, to the lenses, causing irritation upon insertion. Towels, unless freshly laundered on high temperature wash, are frequently contaminated with large quantities of bacteria and, as such, should be avoided when handling lenses
Dust, lint and other debris may collect on the outside of contact lenses. Again, hand contact with this material, before handling contact lenses, may transfer it to the lenses themselves. Rinsing the case under a source of clean running water, before opening it, can help alleviate this problem. Next the lens should be removed from its case and inspected for defects (e.g. splits, folds, lint). A 'gritty' or rough appearance to the lens surface may indicate that a considerable quantity of proteins, lipids and debris has built up on it and that additional cleaning is required; this is often accompanied and felt by unusually high irritation upon insertion
While asleep, oxygen is supplied from the blood vessels in the back of the eyelid. A lens in the eye while asleep, can hinder the passage of oxygen to the cornea causing oxygen starvation to the cornea which can result in serious complications, such as corneal ulcer that, if left untreated, can permanently decrease vision
Wearing lenses designed for daily wear overnight also has an increased incidence of corneal neovascularization (small vessels growing int the clear cornea). This condition, once it sets in, cannot be reversed and will eventually spoil vision acuity through diminishing corneal transparency
Insertion and removal
The guidelines listed here should in no way replace the instructions you got from your Eye Care practitioner. The steps listed here are industry suggested guidelines, but should you have any queries please call your trusted practitioner directly. Your Eyecare Practitioner always knows best.
Before you put your lenses in for the first time
- Always keep your glasses with you. You may sometimes need to give your eyes a break from your contact lenses and you’ll want your glasses handy.
- Stock up on contact lens solution. You don’t want to wait until the end of the day to find out that you’re out of solution. And never use water to clean your lenses! It can contaminate them and harm your eyes.
- Don’t ignore discomfort. If your lens causes pain, this can mean a speck of debris is on your lens or another problem. Always remove the lens, clean and disinfect it, and check it for scratches or tears before reinserting it.
Follow these steps when Inserting your Contact lenses
Remember, always wash your hands first. Washing your hands with an oil-free soap can prevent germs from getting on your lenses and also help keep them free from smudges or oily film.
Start with the same eye every time. Just like lenses in your glasses, your left and right contact lenses are made differently to give you the best possible vision correction for each eye. Always start with the same lens every time so that you don’t accidentally switch them. Tip: If you’re right-handed, start with the right lens. If you’re left-handed, go lefty first.
Scoop the lens out carefully. Put the lens on the end of your finger and hold it up to the light so you can see it clearly. Is it curved upward like a bowl? Then you’re almost there! Check it for tears or scratches, clean and disinfect it with lens solution, and you’re ready.
Insert the lens. Use your free hand to hold up your upper eyelid. Use the middle finger of the hand holding your lens to pull your lower eyelid down. Holding the lens on the tip of your index finger, place it on your eye. Once inserted, look from side to side to position the lens over the colored part of your eye. Make sure the lens is comfortably seated on your eye, so it doesn’t pop out.
Now blink and you’re done. Just blink naturally and take a look in the mirror. If everything looks and feels okay, enjoy your glasses-free, clear vision and go about your day!
Follow these steps when Removing your Contact lensesAs you follow these steps, remember to go slow and be gentle. Just like when you put your lenses in, always start with the same side, right or left. This will help avoid switching your right and left lenses. And always wash your hands first!
Stand in front of a well-lit mirror.
Using your non-dominant hand, raise your upper eyelid away from your eye with your index finger.
With your dominant hand, use your middle finger to pull your lower eyelid down.
With the tips of your index finger and thumb, gently squeeze the lens to pull it down and away from your eye. Don’t squeeze so hard that it folds or pinches.
Place the lens in the palm of your other hand and cup that hand slightly. Squeeze fresh multipurpose lens solution onto the surface of the lens. See Caring for Your Contact Lenses for more details on how to clean and disinfect your lenses.
If you’re using contact lenses meant to be worn for multiple days before replacement, make sure you put them in a case that has “L” for left and “R” for right clearly marked, so you don’t mix them up. Follow the instructions that came with your cleaning and disinfecting solution.
Lens care varies depending on material and wear schedule. Daily disposables are discarded after a single use and thus require no cleaning. Other lenses need regular cleaning and disinfecting to prevent surface coating and infections. There are many ways to clean and care for your lenses.
This is the most common method for rinsing, disinfecting, cleaning, and storing soft lenses. The latest multipurpose solutions also contain ingredients that improve the surface wetability and comfort of silicone hydrogel lenses.
Hydrogen peroxide systems:
Hydrogen peroxide can be used to disinfect contact lenses. Care should be taken not to get hydrogen peroxide in the eye because it is very painful and irritating. The instructions need to be followed as directed. Hydrogen Peroxide solution should never be put directly into the eye.
Used to clean lenses on a daily basis. A few drops of cleaner are applied to the lens while it rests in the palm of the hand; the lens is rubbed for about 20 seconds with a clean fingertip (depending on the product) on each side. Lens must then be rinsed with daily cleaner. Aside from cleaning the contact lenses, it is highly advised to also clean the cases to avoid any possible infection. Replacing the case monthly and storing it in a clean and safe environment is also recommended.
Researchers have linked ultraviolet (UV) light to the formation of cataracts. Exposure to excessive UV light also may result in a condition called photokeratitis, that's why some contact lenses now contain a UV-blocking agent. You can't tell if a contact lens has a UV blocker just by looking at it. The blocking agent is clear, so as not to disturb vision. The contact lens packaging will specify if the product has a UV blocker, or you can ask your eye care practitioner.
Very important: UV-blocking contacts are not meant to replace sunglasses. A contact lens covers only your cornea, not your entire eye.
However, UV-blocking contact lenses do help protect the portion of the white of your eye that is covered from formation of growths such as pingueculae and pterygia.
Sunglasses with UV protection can cover more of your eye and the parts of your face that surround the eye, depending on the size of the sunglass lens. That's why contacts with UV blockers are designed to complement sunglass use as an added protection.
Contact lenses are generally safe as long as they are used correctly. Complications from contact lens wear affects roughly 5% of wearers yearly. Factors leading to eye damage varies, and improper use of a contact lens may affect the eyelid, the conjunctiva, and, most of all, the whole structure of the cornea. Poor lens care can lead to infections by various microorganisms
Many complications arise when contact lenses are worn not as prescribed (improper wear schedule or lens replacement). Sleeping in lenses not designed or approved for extended wear is a common cause of complications. Many people go too long before replacing their contacts, wearing lenses designed for 1, 14, or 30 days of wear for multiple months or years. While this does save on the cost of lenses, it risks permanent damage to the eye and even loss of sight.
Mishandling of contact lenses can also cause problems. Corneal abrasions can increase the chances of infection. When combined with improper cleaning and disinfection of the lens, a risk of infection further increases. Decreased corneal sensitivity after extended contact lens wear may cause a patient to miss some of the earliest symptoms of such complications.
- DO always rub contact lenses when you clean them, even if using a "no-rub" solution.
- DO make sure contact lenses and lens storage cases are cleaned and disinfected regularly.
- DO replace contact lenses regularly, according to your Eye Care Practitioner's directions.
- DO put your lenses in before applying Eye Makeup.
- DO always wash hands before handling contact lenses.
- DO remove lenses before removing Eye Makeup.
- DO have an annual checkup to ensure your eyes remain healthy and to check lens powers.
- DON'T place contact lenses in your mouth or use your saliva to wet them.
- DON'T "top off" old solution in your contact lens case. Instead, discard old solution and replace it with fresh solution.
- DON’T apply eyeliner between your lashes and your eye.
- Why do Contact Lenses Expire – All about vision (liz Segre)
- WikiHow to do anything
- Dangers of Expired Contact Lenses - Twenty Twenty Eye Care
- Contact Lenses: The Risks You Need to Know - Medscape
- All about wearing contact lenses
- Effects of long-term contact lens wear on the cornea
- Science Daily
- Cooper Vision – inserting your contact lenses
- CooperVision – removing your contact lenses
- Acuvue Contact Lenses