precaution while using contact lenses
What Are Contact Lenses
. Contact lenses are medical devices worn directly on the cornea of the eye. Like eyeglasses, contact lenses help to correct refractive errors and perform this function by adding or subtracting focusing power to the eyes cornea and lens. Contacts provide a safe and effective way to correct vision when used with care and proper supervision. They can offer a good alternative to eyeglasses, depending on your eyes and your lifestyle. Over 24 million pe
Types of Contact Lenses
. These are the most common type of contact lenses currently prescribed. These lenses are made materials that incorporate water, which makes them soft and flexible and allows oxygen to reach the cornea. 1Daily disposable lenses: Although generally more expensive, they carry a lower infection risk. Two week or monthly disposable lenses: for daily wear. 2Toric contact lenses: Correct moderate astigmatism. Bifocal contact lenses: can be helpful for pa
. These lenses are also known as RGPs. They are rigid or hard lenses made of plastics combined with other materialssuch as silicone and fluoropolymersthat allow oxygen in the air to pass directly through the lens. For this reason, they are called gas permeable.
. Dailywear lenses should never be worn as extendedwear lenses. Misuse can lead to temporary and potentially sight threatening damage to the cornea. People who wear any type of lens overnight have a greater chance of developing infections of the cornea. These infections are often due to poor cleaning and lens care. Improper over wearing of contact lenses can result in intolerance, leading to the inability to wear contact lenses.
Gas permeable lenses
. Gas permeable lenses can potentially scratch the cornea if the lens does not fit properly or if the lens is worn while sleeping. They are also more likely to slide off the cornea and become hidden under the lid. Gas permeable lenses traditionally had a reputation for popping out of the eye. Newer lens designs have minimized the chance of losing a contact even during vigorous exercise.
Soft extendedwear contacts
. Gaspermeable lenses and soft extendedwear contacts are the most likely to have protein buildup and cause lensrelated allergies. Protein buildup results in discomfort, blurring, and intolerance to the lenses. Thus, nightly disinfection becomes imperative and you mayneed special cleaning solutions to dissolve the protein.
Who Should NOT Wear Contact Lenses
. Most people who need vision correction can wear contact lenses. Among the conditions that might keep you from wearing contact lenses are:1Frequent eye infections. 2Severe allergies. 3Dry eye (improper tear film). 4A work environment that is very dusty or dirty. 5Inability to handle and care for the lenses properly.
Are Contacts for You
. Whether or not contact lenses are a good choice for you depends on: 1Individual needs and expectations. 2Patience and motivation during the initial adjustment period to contact lens wear. 3Adhering to contact lens guidelines for wear, disinfecting, and cleaning. 4Diagnosis and treatment of conditions that may prevent contact lens wear.
How to Care for Your Lenses
. Contact lenses must be properly cleaned and disinfected when you remove them to kill germs and prevent infections. All contact lens cases should be cleaned daily and it is recommended that you replace your case every three months. Never reuse your contact lens solution. Dispose of contact lens solution in the lens case after each use and let the case air dry. Do not put your lens in your mouth and then in your eye. Never use homemade cleaning sol
Wear Your Lenses Properly
. 1Wash your hands with soap prior to handling contact lenses or touching your eye.2Do not share your lenses with someone else.3Do not use fashion lenses (nonprescription color lenses) unless they are fitted by an optometrist.4Do not purchase bootleg lenses.5Wear lenses on the schedule prescribed by your optometrist.6Dispose of your lenses at the interval prescribed by your optometrist.
Dont use Contact Lenses
. 1Your eye is painful.2You are sensitive to light.3Your eye is red for more than two days.4You have discharge from your eye.5You have blurry vision.6Your eye feels scratchy.Remember to book yearly contact lens and eye health exams for the protection of you eyes.
Safest medical devices
. Contact lenses are one of the safest medical devices when worn responsibly, says Thomas L. Steinemann, MD, a professor of ophthalmology at Case Western Reserve University in Cleveland and a spokesperson for the American Academy of Ophthalmology. While contact lens use is safe, not caring for contact lenses properly or failing to follow contact lens safety rules can lead to serious problems. Contact lenses can be a potential point for infection, s
Get a contact lens prescription from an eye doctor
. Have your lenses fitted by a qualifiedeye care professional, says Steinemann. Also be sure to get instruction on proper lens care. Make sure that the contact lens is on the cornea of the eye. Cover the opposite eye, and if your vision is blurry, inspect the upper area of your eye by lifting the upper lid and looking into a mirror, and the lower area by gently pulling down the lower lid.
Dont wear contact lenses overnight
. When you close your eyes with your lenses in place, youre reducing oxygen, says Steinemann. The surface of the eye becomes more vulnerable to infection. Also, you have a lens being closed against the eye any germs on the lens are being slammed against the cornea.
Dont wear your contact lenses in the shower or while swimming
. Lakes, rivers, sea water, swimming pools, and even tap water can all harbor an organism calledacanthamoeba, which can cause eye infection. Wearing contact lenses while swimming, showering, or doing other waterrelated activities can lead to seriousacanthamoebainfections of the eye.
Dont reuse contact lens solution
. You may think youre saving money by doing so, but the disinfecting capability of the solution is gone, says Steinemann. Use fresh solution every time you store your lenses in their case. There are two common methods for removing contacts. Follow the one that your doctor recommended, and if either of these methods are difficult for you, your doctor can recommend another method of removal.
Dont use saline solution for contact lens cleaning or disinfection
. Saline solution is simply sterile salt water. It will not clean or disinfect. Be sure to choose a solution that includes disinfectant. For the pinching method, look up, slide the lens to the lower part of the eye using the forefinger, pinch the lens between the forefinger and thumb, and remove the lens. The pinching method should not be harmful, your fingernails should not touch the lens or your eye.
Replace your contact lens case every two to three months
. Lens cases get dirty, just like a toothbrush, says Steinemann. The forefinger and thumb method means you dont have to actually touch your eye. Place your hand or a towel under your eye to catch the lens. Place your forefinger on the center of the upper lid, and your thumb on the center of the lower lid and force a blink. The lens should fall out onto your hand or the towel.
Never use saliva as a wetting agent
. Your mouth is one of the dirtiest places in your body, says Steinemann. After you remove the contact, follow care instructions given to you by your doctor, or on the case of the contact. If they are single use contacts, discard the lens immediately. If they are for multiple use, immediately follow care instructions.
Take out your contacts if they are bothering you
. It seems like common sense, but it can be easy to ignore irritation when youre busy or distracted. Never put up with irritation, as it could be sign of an infection or other problem. Make sure to clean, rinse, then disinfect your lenses after you remove them. Cleaning and rinsing the contacts removes any film, dirt, and anything that may have accumulated while you were wearing them. Disinfecting them is important for the elimination of germs.
Before handling your contact lenses
. Wash your hands with soap and water and dry with a lintfree towel. When you first get contacts, make sure to put them on and remove them while still with your optician. You will be given a manual with instructions on caring for your contacts, and information on what to do if something goes wrong. Follow these instructions carefully as failure to do so can result in serious problems, such as infection or damage to your eyes.
To remove lenses
. After you take out each contact lens from your eyes, gently rub with solution. Then rinse each lens with fresh solution before storing them for disinfection; be sure you squeeze enough solution into each case compartment to cover each lens. Even if the packaging of the solution you use reads no rub, you should still clean each lens to remove any germs, says Steinemann.
To put in lenses
. After disinfecting your contact lenses according to the product directions on your solution bottle andbeforeyou put them back in your eyes, rinse off each contact lens with fresh solution. Discard used solution, rinse out the lens case with fresh solution (not water), and let the case air dry.
Some people should not use contact lenses for vision correction
. Some people should not use contact lenses for vision correction. They include: 1Anyone who is too busy to be compliant with contact lens safety measures and thorough hygiene habits. 2People who work where there is a lot of debris in the air, such as sawdust. 3People who havedry eye problems. When you put a lens in the eye, it rests on tear film, says Steinemann. If you dont make enough tears, you could be at increased risk for infection.Contact l
Always remove your eye makeup after removing your lenses
. 1. If you wear eye makeup or cosmetics, apply your eye makeup after wearing your lenses. Also, always remove your eye makeup after removing your lenses. People who have dry eye problems. When you put a lens in the eye, it rests on tear film, says Steinemann. If you dont make enough tears, you could be at increased risk for infection.
In order to avoid eye infections
. In order to avoid eye infections, you should avoid handling your contact lenses excessively before wearing them. If you fail to wear your contact lens from the first try, wet and clean your contact lenses with a few fresh drops of solution before trying to wear them again.
Avoid having your eyes exposed to cream lotions
. While wearing contact lenses, always avoid having your eyes exposed to cream lotions, hair spray, hair dryers, or deodorants. Such items will damage your contact lenses and may cause problems for your eyes. Anyone who is too busy to be compliant with contact lens safety measures and thorough hygiene habits.
Avoid in presence of environmental fumes
. 1. Always avoid wearing your contact lenses in the presence of environmental fumes, excessive smoke, dust or vapors and in severe windy conditions. Also, avoid wearing your contact lenses in the presence of chemicals, paint thinner, household cleaning substances, unusually polluted air, intense heat or any other abnormal atmospheric conditions.
In case your eyes become red
. 1. In case your eyes become red while wearing your contact lenses, or if you feel any discomfort wearing them and/or in the case of feeling any sort of a stinging or burning sensation or itching and irritation, excessive tearing, eye dryness, reduced vision sharpness and poor vision acuity, blurred vision, rainbows or halos surrounding objects, photophobia or severe sensitivity to light, unusual eye secretions, remove your contact lenses immediat
What went wrong
. The FDA has received several reports of corneal ulcers, keratitis, and other eye infections associated with using daily disposable contact lenses for longer than the period recommended. Ophthalmologists and other eye care professionals believe the reported problems are caused by contact lens wearers poor hygiene and failure to follow directions when using and caring for these types of lenses. Reports of consumers wearing daily disposable contact
What precautions can you take
. Help wearers of disposable soft contact lenses reduce the risk of eye infection and other problems by teaching them to follow these guidelines: Read the labeling on the use and care of contact lenses and strictly follow the directions. To avoid contamination, before and after handling contact lenses, wash your hands with mild soap that doesnt contain cold cream, lotion, or oily cosmetics. Then rinse your hands well and dry them with a lintfree to
Keep contact lenses clean
. Keep contact lenses clean at all times by using the recommended contact lens solutions as directed. Dont use sterile water or nonsterile solutions including homemade solutions, distilled water, or water from the tap, a bottle, the ocean, pool, or lake. Dont use your saliva to wet your lenses.
keep the bottle tightly closed
. Be careful with contact lens solution. Dont transfer it into another container because this can cause contamination. Dont let the tip of the bottle touch anything and keep the bottle tightly closed when youre not using it. Contact lenses are one of the safest medical devices when worn responsibly, says Thomas L. Steinemann, MD, a professor of ophthalmology at Case Western Reserve University in Cleveland and a spokesperson for the American Academy
Make sure its not damaged
. Examine each contact lens before inserting it to make sure its not damaged. Discard any damaged lenses. While contact lens use is safe, not caring for contact lenses properly or failing to follow contact lens safety rules can lead to serious problems. Contact lenses can be a potential point for infection, says Dr. Steinemann. No matter how careful you are, germs are on our hands, eyelids, everywhere. When germs such as bacteria and fungi are on t
Dont wear contact lenses longer
. Dont wear contact lenses longer than the period recommended. Immediately remove your lenses and seek medical care for vision changes, eye discomfort, redness, excessive tearing, photophobia, and foreign body sensations. Millions of people wear contact lenses as a convenient way to correct their vision. But all contact lens wearers must be vigilant about one thing contact lens safety.
Fusarium Infections Among Contact Lens Wearers
. Bausch and Lomb has permanently suspended U.S. sales of ReNu
If you use ReNu solutions Mass
. Any bottles of ReNu with MoistureLoc should be thrown out and other products should be used. Patients currently using ReNu should change to another disinfecting solution.Contact the eye care provider who prescribes your lenses to see which alternative solution is recommended for your particular contact lenses. Do not use contact lenses if either eye is red, uncomfortable or sensitive to light. Remove your contact lenses immediately if these sympt
Suggestions for caring for your contact lenses
. Carefully and regularly clean contact lenses, as directed by the eye care provider who prescribed them and the patient information included with lens care products. Wash your hands with soap and water before handling your contact lenses. Rub the contact lenses with fingers (if required by the particular disinfecting solution) and rinse thoroughly before soaking the lenses overnight in enough multipurpose solution to completely cover the lenses.
Store lenses in the proper case
. Store lenses in the proper case and replace the lens storage case at least every three months. Replace sooner if the case appears damaged or dirty. Clean the contact lens case after each use and keep the case open and dry between cleanings.
Put on soft contact lenses
. Put on soft contact lenses before applying makeup. Do not wear contact lenses while swimming. The chance of infection from fungi, bacteria, or amoeba is much greater if you are wearing contact lenses. Wash your hands thoroughly with soap and water before touching your contact lens or eye. If the water is not drinkable, use bottled water to wash your hands.
Avoid lashextending mascara
. Avoid lashextending mascara, which has fibers that can irritate the eyes, and waterproof mascara, which cannot be easily removed with water and may stain soft contact lenses. If you will be in an area where basic hygiene will be difficult, consider switching to daily disposable contact lenses, if you havent already. These will allow you to throw your lenses away each night without needing to clean or store them.
Choose lotions before applying contacts
. Choose an oilfree moisturizeror lotions before applying contacts. They can leave film on your lenses. Bring a copy of your prescriptions for glasses and contact lenses. These numbers are recognized globally and will be useful in case anything happens.
Use hairspray before putting on your contacts
. Use hairspray before putting on your contacts. If you use hairspray while you are wearing your contacts, close your eyes during spraying and for a few seconds afterwards. Eyes are vulnerable to injury and infection, especially if you are using contact lenses while traveling. However, eyes can usually be kept safe with just a few simple precautions.
Blink your eyes frequently while under a hair drier
. Blink your eyes frequently while under a hair drier or blower to keep your eyes from getting too dry. Contact lenses are small, thin discs made of a transparent material. The outer surfaces are customshaped to correct or improve vision and the inner side is carefully formed to fit the surface of the cornea (the clear, front covering of the eye including the iris and pupil). Today, the lenses are typically soft (flexible) but hard (rigid) are stil
Keep false eyelash cement
. Keep false eyelash cement, nail polish and remover, perfume and cologne away from the lenses. They can damage the plastic. Contact lenses can be a safe and effective way to correct vision for most people. However, people who wear them must follow the directions of their eye specialist this care includes how long the lenses can be worn continuously, how they should be cleaned and stored, and the good hygiene practices to follow when wearing or ha
Hypoallergenic liquid foundations
. Choose waterbased, hypoallergenic liquid foundations. Cream makeup may leave a film on your lenses. Many people wear contact lenses because they prefer them to eye glasses contact lenses do not slip down your nose or fog up in the wintertime. A few people, however, must wear contact lenses to have adequate vision (for example, after cataract surgery, or for medical conditions such as keratoconus a deformity of the cornea).
Soft contact lenses care
. You should be extra careful because soft contact lenses are very delicate as compared to hard contact lenses. Use only those lens cleaners that are designed to clean soft lens. Some soft contact lenses may requireheatcleaning process. Consult your eye doctor or optician regarding the same.
Hard contact lenses cleaning
. The hard contact lenses are much more long lasting than the soft contact lenses. These lenses also require a special solution which is designed for cleaning them. Take all required precaution while using them and follow the cleaning process religiously, if youvalueyour eyes.
Cleaners for contact lenses
. Depending upon the kind of brand you use and the amount of protein your eye deposits on your lenses, your doctor may recommend a required product for its removal. Usually it is a protein removal cleaner. Products for removing protein include enzymatic cleaners and daily protein removal liquids. Multipurposesolution, saline solutions, daily cleaners, hydrogen peroxide and enzyme tablets are some of the products used forcleaningcontact lenses.
Benefits of Wearing Contact Lens
. Technological advances have increased the number of patients who can now wear contact lens. Peripheral vision can be better with contacts than with a pair of glasses. Contact lens are automatically cleaned with each blink of the eyelid. Contact lens do not fog in cool temperatures or become wet when you are in rain. Contact lens can be worn safely during sports such as golf, soccer or basketball.
. Infections are rare, but if they occur they should be treated as an emergency. Symptoms of infection are blurry vision, redness, pain, additional tearing with or without a discharge. If this occurs, remove your contact lens and notify us immediately. Put your glasses on if any of the symptoms above occur. Always have a current pair of glasses on hand.
Requirements for Wearing Contact Lens
. 1Expert fitting and comprehensive training for their care. 2Conscientious care by the patient. 3Periodic followup care. 4A complete eye exam prior to your fitting. A prescription is valid for one year per Arkansas law. Eye exams, if needed, are available by appointment at the Jones Eye Institute.
. In the event you are unsuccessful in wearing contact lens, you may return the lens within 60 days for full refund less the restocking fee. You will be responsible for the fitting fee. If a contact lens is damaged, torn or cracked within the first 3 weeks, replacement will be provided at 50% off standard replacement cost. Specially designed lens are available if needed. Fees will be explained before ordering.
Dispose of Your Contact Lenses as Prescribed
. After the accumulated wearing period prescribed by your Master Eye Associates professional, your contact lenses should be discarded. By replacing your contact lenses on a regular basis, lens deposits, which can affect vision and cause irritation and discomfort to the eye, have little chance to build up over time as with conventional lens wear. When you discard the lens, you dispose of potential deposit buildup problems. Remember that the first th
Remove or Do Not Use Your Contact Lenses if you have
. 1Reduced vision (visual acuity) with your contacts. 2Pain in or around your eyes that persists for more than one hour. 3Any eye disease, injury or abnormality that affects thecornea,conjunctivaor eyelids. 4Any previously diagnosed condition that makes contact lens wear uncomfortable. Severedry eye. 5Reduced corneal sensitivity (corneal hypoesthesia) 6Any systemic disease that may affect the eye or be exaggerated by wearing contact lenses. 7Allerg
Risk of Infection or Injury
. 1Problems with contact lenses or lens care products could result in serious injury to the eye. Proper use and care of your contact lenses and lens care products, including lens cases, are essential for the safe use of these products.2 Eye problems, including sores or lesions on the cornea (corneal ulcers) can develop very rapidly and lead to serious consequences including loss of vision. 4The risk of an infected sore or lesion on the cornea (ulce
If you experience eye discomfort
. If you experience eye discomfort, excessive tearing, vision changes, redness of the eye or other problems, you should immediately remove your lenses and promptly contact your Master Eye Associates professionals. It is recommended that you see Master Eye Associates routinely as directed or at least annually.
UV ABSORBING CONTACT LENSES
. UV (ultraviolet light) ABSORBING CONTACT LENSESare not substitutes for protective UV absorbing eyewear such as UV absorbing goggles or sunglasses because they do not completely cover the eye and surrounding area. You should continue to use UV absorbing eyewear. Longterm exposure to UV radiation is one of the risk factors associated with cataracts. Exposure is based on a number of factors such as environmental conditions (altitude, geography, clou
. DO NOTuse if the sterile blister package is opened or damaged. Before leaving your Master Eye Associates office, you should be able to quickly remove your lenses or you should have someone else available who can remove the lenses for you. If you do not feel that you are qualified to remove your lenses promptly, do not wear them until you can.
DO NOTtouch your contact lenses with your fingers
. DO NOTtouch your contact lenses with your fingers or hands if they are not completely clean, because tiny lens scratches may occur, causing unclear vision and/or injury to your eye. Contact lenses can cause some problems that do not produce any symptoms that the contact lens wearer may not notice. For this reason, contact lens wearers should have regular checkups with a specialist who prescribes and fits contact lenses.
Lens Wearing Precautions
. You should remove your lenses immediately if your eyes become red or irritated. Neverwear your lenses beyond the amount of time recommended by yourMaster EyeDoctor. If aerosol (spray) products, such as hair spray, are used while wearing lenses, exercise caution andkeep your eyes closeduntil the spray has settled. Avoidall harmful or irritating vapors and fumes while wearing your contacts. Exposing contact lenses to water during swimming or while
. Different lens care products cannot always be used together, and not all products are safe for use with all lenses. Use only recommended solutions. NEVERuse solutions recommended for conventional hard contact lenses only. Chemical disinfection solutionsshould not beused with heat unless specifically indicated on product labeling for use in both heat and chemical disinfection. Alwaysuse fresh lens care products and lenses before the expiration dat
. If you wear your contact lenses to correctpresbyopiausing monovision youmay notbe able to get the best corrected visual acuity for either far or near vision. You should drive or operate machinery only when you feel your vision is completely adequate. Otherwise do not drive or operate machinery while wearing monovision or bifocal contacts. Alwayscontact your eye doctor before using any medicine in your eyes.
Be awarethat certain medications
. Be awarethat certain medications, such as antihistamines, decongestants, diuretics, muscle relaxants, tranquilizers and those for motion sickness may cause dryness of the eye, increased lens awareness (feeling of the lens in the eye) or blurred vision. Always inform your eye care professional if you experience any problems with your lenses while taking such medications. Depending on the severity, your eye care professional may prescribe the use o
Prepare the Lens for Wearing
. Cleanliness is the first and most important aspect of proper contact lens care. In particular, your hands should be clean and free of any foreign substances when you handle your lenses. The procedures are: Wash your hands thoroughly, rinse completely and dry with a lintfree towel before touching your lenses. Avoid the use of soaps containing cold cream, lotion, or oily cosmetics before handling your lenses, since these substances may come into co
Opening the Multipack and Lens Package Multipack
. Each multipack contains individually packaged lenses. Each lens comes in its own lens package designed to keep it sterile. Keep your lenses inside the multipack for storage until you are ready to use them. The critical point to remember is that contact lenses are not intended to be used as protective devices. They are not a substitute for personal protective equipment (PPE) if eye and face protection is required for certain work operations then
. A. Peel back the foil closure to reveal the lens. b. Place a finger on the lens and slide the lens up the side of the bowl of the lens package until it is free of the container. Occasionally, a lens may stick to the inside surface of the foil when opened or to the plastic package itself. This will not affect the sterility of the lens. It is still perfectly safe to use. Carefully remove and inspect the lens following the handling instructions.
Handling the Lenses
. When you first get your lenses, be sure that you are able to put the lenses on and remove them before leaving Master Eye Associates office. Develop the habit of always working with the same lens first to avoid mixups. Remove the lens from its storage case and examine it to be sure that it is moist, clean, clear, and free of any nicks or tears. If the lens appears damaged, DO NOT use it.
. Always be sure the lens is on thecornea(in the center of your eye) before attempting to remove it. Determine this by covering the other eye. If vision is blurred, the lens is either on the white part of the eye or it is not on the eye at all. To locate the lens, inspect the upper area of the eye by looking down into a mirror while pulling the upper lid up. Then inspect the lower area by pulling the lower lid down.
For Daily Disposable Wear
. There is no cleaning or disinfection needed with your contact lenses if they are prescribed for daily disposable wear. Always dispose of lenses when they are removed and have replacement lenses or glassesavailable. Lenses should only be cleaned, rinsed and disinfected on an emergency basis when replacement lenses or glasses are not available. For EMERGENCY LENS CARE ONLY, refer to the instructions below for cleaning, rinsing and disinfecting your
For Frequent Replacement Wear
. For continued safe and comfortable wearing of your lenses, it is important that you first clean and rinse, then disinfect your lenses after each removal, using the lens care products and procedures recommended by your Eye Care Professional. Cleaning and rinsing are necessary to remove mucus, secretions, films or deposits that may have built up on your lenses during wearing.The ideal time to clean your lenses is immediately after removing them. Di
Basic Contact Care
. Make sure to clean, rinse, then disinfect your lenses after you remove them. Cleaning and rinsing the contacts removes any film, dirt, and anything that may have accumulated while you were wearing them. Disinfecting them is important for the elimination ofgerms. When you first get contacts, make sure to put them on and remove them while still with your optician. You will be given a manual with instructions on caring for your contacts, and informa
Reusable contact lenses
. For lenses that are reused, rather than worn once and discarded, the following guidance applies. After removing your contact lenses its essential that you disinfect them as this prevents harmful organisms building up on the lens. Your practitioner will advise you on the best contact lenses for youand how to care for them. This may include extra cleaning procedures, such as rubbing or rinsing. Disinfection tips: To disinfect your lenses, soak them
. Daily disposable lenses dont need cleaning or disinfecting because they are only worn once and then thrown away. Dont reuse these lenses as theyre unsuitable for repeated use. Even if you wear daily disposables, its still important tohaveregular checkupswith your practitioner.
Extended wear lenses
. Extendedwear lenses are specially designed for wearing overnight, and can be worn continuously for up to a month before being discarded. Dont sleep while wearing lenses unless your practitioner advises it. They will also advise you on how to look after the lenses if you need to remove them temporarily. You may need more frequent checkups if you wear this type of lens.