Generality
Contact lenses are medical devices to be applied to the front surface of the eye. In most cases, they are used as an alternative to glasses, for the correction of refractive defects, but there are also contact lenses intended for other medical or aesthetic applications.
Many people wear contact lenses without problems. However, to avoid infections and other vision-threatening complications, it is necessary to carefully follow the instructions for their correct application and maintenance. Equally important is the preventive medical evaluation, which ensures that the patient is an appropriate candidate for contact lenses and is able to handle them safely.
Before applying them
The type of contact lens prescribed determines the different management methods.
Application and removal
There are some differences regarding the correct procedure for applying and removing a contact lens. Depending on its anatomical characteristics, the type of lens (soft or rigid), manual ability and the visual limitations to which it is subjected, each patient must find the technique that is personally best. In all cases, these procedures require some training and practice on the part of the user. Each corrective lens is packaged in a sealed and sterile blister, which must indicate the correct alcohol content and expiration date. The contact lens must be moist and clean, free of cuts, scratches or particles. If the device looks rough, additional cleaning may be required. A damaged or dry contact lens should never be used.
How to apply Contact Lenses
Contact lenses are typically applied in the eye, placing them on the fingertip of the dry index finger, with the concave side facing upwards. The other hand can be used to keep the eye open.
- The rigid contact lenses must be placed directly on the cornea, while the soft ones can be placed on the conjunctiva, from where they can slide into position, gently winking.
Problems can arise if the soft lens bends or flips, slips off the finger or adheres tightly (typically if the finger is wet). When the contact lens enters the eye it should be comfortable. A brief period of irritation can be normal, if caused by a difference in pH and / or salinity between the saline solution and the tears. If the discomfort persists, the lens may be dirty or damaged. Removal from the eye, cleaning, inspection and correct orientation should resolve the problem.
How to Remove Contact Lenses
Improperly removing contact lenses can cause device damage and eye injuries, so care must be taken during this procedure.
- Rigid contact lenses can be removed by pulling the outer corner of the eyelid with a finger and then winking. The increased tension of the eyelid margins, against the edge of the lens allows to break the capillary action that makes it adhere to the corneal surface, while the other hand is cupped, under the eye, to receive it.
- A soft contact lens can be removed by pinching its edge with thumb and forefinger. It is also possible to push it far enough to the side of the eye to make it bend outwards. Using these techniques on a rigid contact lens could abrade the cornea. Alternatively, some small flexible plastic instruments can be used, similar to tweezers or suction cups, specific for the removal of these devices.
Common Errors
In general, it is not difficult to wear and wear contact lenses; in this sense, following the doctor's advice allows you to avoid most of the errors and the consequent complications.
The most common problem among patients is the improper daily care of contact lenses. Proper management does not stop at cleaning and disinfection of the device itself, since this must also be extended to the case where it is stored. Patients who have been prescribed prolonged use lenses often mistakenly think they are exempt from the daily cleaning process. Furthermore, even if they are approved for use at night, it is often recommended to remove them before going to sleep, as wearing these devices for excessively long times increases the risk of eye infections.
It is important never to exchange contact lenses with another person, especially if someone has already worn them; this behavior facilitates the transfer of particles or potential pathogens. Another common mistake that people make is to buy contact lenses from non-competent traders (such as markets, internet and beauty salons); in this regard, please note that non-compliant devices can cause permanent eye damage. Therefore, people should never buy and wear contact lenses without a medical guide and a valid prescription. Another problem that many people do not consider is the protection of the eyes from the sun while wearing contact lenses. Some devices include UV protection, but this is not comparable to the shielding of ultraviolet light offered by sunglasses.
Cost
Each ophthalmologist (or optometrist) determines his own rates independently. A number of factors can go to determine the initial cost of contact lenses; these elements can include all those professional performances necessary to select the lens that best suits the patient. Some services and materials that can be included in the initial cost are:
- A thorough diagnostic examination;
- A contact lens maintenance kit;
- Training for the use and care of lenses;
- Outpatient follow-up visits, for a specified period of time.
If the patient already brings contact lenses but needs to replace them, the total could include the actual cost of the same, plus the fee for the doctor's professional services.
Maintenance
Proper management of contact lenses is essential for maintaining eye health. Regardless of the type of lens used, some general guidelines must be followed:
- Wear and replace contact lenses according to the schedule prescribed by the ophthalmologist.
- Before handling the lenses, wash your hands with water and neutral soap, then rinse them and dry them with a clean, lint-free cloth.
- Clean the contact lenses according to the eye care professional's instructions and the manufacturer's guidelines.
- Do not reuse or top up the old disinfectant solution.
- Do not use saline or humidifying drops to disinfect contact lenses. None of these solutions are effective or approved for this purpose.
- Do not put contact lenses in your mouth to moisten them. Saliva is not a sterile solution.
- Be sure to clean, rub and rinse contact lenses every time you remove them. The delicate rubbing with fingers (obviously clean) helps to remove microbes and residues.
- In case of difficulty in following the cleaning procedure, it is useful to communicate it to the ophthalmologist, who could simplify the operations or prescribe disposable lenses.
- Remove contact lenses before any activity involving '‹contact with water, including showering or swimming.
- Store reusable contact lenses in the correct case.
- The cases must be rubbed and rinsed with the sterile solution for contact lenses (never use distilled water or tap water), emptied and left open to dry after each use.
- Replace storage cases regularly, at least once every three months.
- Storage cases can be a source of contamination and infection. Do not use if broken or damaged.
Cleaning and disinfection
Types of Solutions
Multi-purpose solutions : the most common method for rinsing, disinfecting, cleaning and storing soft lenses. New generations of polyfunctional solutions are effective against bacteria, fungi and Acanthamoeba and contain ingredients that improve the wettability and comfort of contact lenses.
Sterile saline solution : used for rinsing contact lenses after cleaning and to prepare them for application. The physiological solutions do not disinfect, therefore they must be used in combination with a disinfection system.
Daily cleanser : should be used on a daily basis, to remove lipid deposits, 'tear' proteins and environmental pollutants that can accumulate on the surface of contact lenses. However, remember that such products do not sterilize the lenses.
Some drops of detergent are applied to the device while resting in the palm of the hand; the lens is then rubbed with the index finger for about 10-20 seconds (depending on the product) and upside down to repeat the procedure on the other side; finally, it is rinsed with a strong saline solution flow to remove any residues.
Hydrogen peroxide : can be used to disinfect contact lenses.
- With the "two-phase" products, hydrogen peroxide must be rinsed thoroughly with saline solution before the lenses can be applied.
- "One-step" systems allow hydrogen peroxide to react completely, so the lenses do not need to be rinsed before insertion, provided that the solution is allowed enough time to react.
Enzymatic detergent : in the form of tablets, it is used for cleaning protein deposits, usually weekly.
How to use contact lens solutions correctly
- Use only commercial preparations recommended by the eye specialist. Certain products should only be used with certain types of contact lenses.
- The solutions may contain preservatives such as thiomersal, benzalkonium chloride and benzyl alcohol. Preservative-free products usually have a short shelf life, but are more suitable for people with allergy or sensitivity to one or more components.
- Do not expose contact lenses to tap water, bottle, distilled or homemade saline. Contact lens exposure to water has been associated with Acanthamoeba keratitis, a severe corneal infection that is particularly resistant to treatment.
- Do not reuse or top up the solution to store contact lenses in storage cases. Discard the entire solution after each use.
- Do not use the contact lens solution beyond the stated expiration date. Buy small bottles, as they are emptied more quickly and are therefore less likely to be contaminated than large packs.
- Do not transfer the contact lens solution into smaller sized travel containers. This can compromise the sterility of the product and expose you to the risk of an eye infection. Keep the bottle tightly closed when you are not using it.
- If contact lenses are not used for a long period of time, consult the instructions to determine if disinfection is appropriate before wearing them. Some experts recommend that, if the lenses are used sporadically, it is better to consider the use of daily "disposable".
Maintain eye health
Keeping your eyes healthy is as important as following the procedures for proper contact lens management.
- Follow the program recommended by the ophthalmologist. Replace contact lenses as recommended and meet expiration dates. Furthermore, before starting the relative treatment, it is a good rule to ask the doctor if it is possible to take any drug or instill a topical eye product (even without a prescription). Some of these products, if used together with contact lenses, can irritate the eyes and cause toxic reactions.
- Another way to ensure eye health is to have regular eye exams. If you wear contact lenses, you should consult the eye specialist at least once a year to make sure that these devices continue to have a precise and appropriate validity. These regular visits are also important to strengthen or adapt the correct maintenance of contact lenses. Finally, it is a good idea to have a pair of prescription glasses available with the most recent prescription if you have problems with the lenses.
- Not smoking. Studies show that contact lens wearers who smoke have a higher rate of adverse reactions than non-smokers.
- Remove contact lenses and immediately consult an ophthalmologist if any of the following symptoms occur: pain or redness in the eyes, blurred vision, sensitivity to light, a foreign body sensation in the eye or excessive tearing. If not treated quickly and properly, eye infections and other complications associated with the use of contact lenses can cause permanent damage or even severe vision loss.
- Pay attention to the use of colored decorative lenses, such as those sold in costume shops or on the internet. These non-corrective products are often promoted as fashion accessories and are easily accessible to consumers. The colored decorative lenses have the potential to permanently damage the eyes. The purchase of contact lenses without a prescription can lead to serious risks for eyesight or eye health, including conjunctivitis, allergic reactions, reduced vision and corneal abrasion, due to the inadequate size or shape of the device.
Contact lenses and cosmetics
- Wash your hands with soap before removing or applying contact lenses, avoiding detergents that contain eye irritants (such as beeswax or lanolin). Some soaps with oils or perfumes, hand creams and moisturizing lotions leave a patina, which can be transferred to the surface of the lenses and cause eye irritation or blurred vision.
- Do not neglect the nails, keeping them short and smooth, to avoid damaging the lenses or scratching the eye.
- Use hair spray, perfumes and deodorants in another room before applying contact lenses.
- Apply eye make-up only after applying contact lenses and removing them before removing make-up. This helps to reduce the likelihood that bacteria and other particles can be transferred to the surface of the device. For the face, prefer an oil-free moisturizer and a hypoallergenic liquid foundation, preferably a water-based one. Avoid mascara with synthetic fibers, which can irritate the eyes, or waterproof products, which can stain the soft contact lenses. Some cosmetics are specifically designed for contact lens wearers, as they are easily removed and do not irritate the eyes.
