Effective Options For
About 125 million people around the world wear contact lenses as an alternative to glasses for the correction of refractive errors (spectacle numbers). Tewari Eye Centre and its dedicated staff offer you various contact lenses options including Soft contact lenses (including disposable), Toric contact lenses, Cosmetic contact lenses, Rigid Gas-permeable (semi-soft) contact lenses.
Low vision aids clinic offers rehabilitative services to patients with low vision in the form of various optical magnifiers, telescopes and electronic low vision aids.
FAQ’s on contact lenses
Contact Lenses (CL) are small, thin, curved transparent discs that are designed to rest on the cornea, the clear front surface of the eye. Contacts cling to the film of tears over the cornea because of surface tension, the same force that causes a drop of water to cling to the side of a glass. Contact lenses are mostly used to correct near-sightedness, far-sightedness and astigmatism. 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. However, one must remember, they are health devices, not commodities or beauty aids, and not everyone can wear them. Also, their use can affect the well being of your eyes and only an optometrist or an ophthalmologist (eye surgeon) is qualified to assess the health of your eye. Your healthy vision is the first priority.
There are basically two types of contact lenses:
- Rigid Gas-permeable (RGP) Contact Lenses which are also known as “semi-soft lenses”
- Soft Contact Lenses Hard Contact Lenses have become obsolete now. Soft lenses can be further classified depending on the type of wear: Daily wear Extended wear Disposable (Quarterly, Monthly, Fortnightly, Weekly and Daily)
RGP (Semi-soft) lenses: RGP lenses are made of special, firm plastics combined with other materials, such as silicone and fluoropolymers, which allow oxygen in the air to pass directly through the lens. These lenses are very durable and typically last longer than soft lenses. RGP lenses provide excellent quality of vision, have a long life, and can correct astigmatism as well as uneven curvature of the cornea. The disadvantages are that these may take a little longer to get used to, it is easier for dust to get behind RGP lenses, causing irritation and discomfort, and one can’t switch back and forth with glasses as easily. However, regular wearers find them comfortable and the visual acuity outstanding. Soft lenses are made of flexible water-absorbent (hydrophilic) material having water content between 30-80%. These lenses are comfortable the moment they are inserted in the eye. They are less likely to dislodge and can be worn for longer periods. However, their biggest disadvantage is that they cannot correct higher degrees of astigmatism. They also need to be changed more frequently.
Daily-wear contact lenses are designed to be removed each day for cleaning, and should be taken out before you sleep or nap. Extended-wear lenses can be worn continuously for up to seven days before they are removed for cleaning, depending on how oxygen-permeable the lens material is. Extended-wear lenses can also be prescribed to be removed each day for cleaning and slept in occasionally when special circumstances arise. Many variables are considered in deciding between daily-wear and extended-wear lenses for each person’s needs. Since the risk of serious eye infections is higher in extended contact-lens wearers, they are generally prescribed in carefully selected individuals who are frequently monitored by eye care professionals. Daily-wear lenses should never be worn as extended-wear lenses. Misuse can lead to temporary and even permanent 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.
While some cosmetics may interfere with contact lens performance and the wearer’s tolerance for contacts, others are safe. Some rules should be followed when using cosmetics: Insert lenses before applying eye makeup and take them out before removing cosmetics. Use hair spray and other aerosols before lenses are inserted. Allow time for the aerosol mist to settle from the air or go to a different area before handling lenses. Completely remove residual cosmetics from you hands with mild, additive-free soap before handling lenses. Use cream shadows instead of powders and avoid using shadows with glitters. Use water based cosmetic formulations. Use hypo-allergenic cosmetics. Avoid using mascaras containing fibers for extra lash length. Avoid using saliva to wet applicators. Don’t apply eyeliners and pencils inside the upper or lower eyelid margin.
Eye exams are important not only to check your prescription but also to evaluate the health of your eyes. This is especially important for contact lens wearers because the contacts could be causing damage to your eyes without necessarily causing any obvious symptoms. Sometimes, one may experience symptoms such as – redness of eyes, stinging, burning or itchy eyes, excessive tears, unusual eye secretions, and changes in vision. Such symptoms could be due to many reasons. On feeling of any discomfort, you should remove and examine your contact lenses immediately. If your lens appears damaged, torn or ripped, do not put the lens back on your eye. Put on a new lens or contact your eye care practitioner to order a new lens. If your lens is not damaged, but the irritation persists, contact your eye doctor immediately.
FAQs On Low Vision Aids
A person is said to have ‘Low Vision’, if he or she has a significant visual handicap in spite of treatment and best correction with standard eyeglasses or contact lenses. ‘Low Vision’ should not be confused with blindness. People with ‘Low Vision’ have a significant visual handicap but they also have significant residual vision. The residual vision may be insufficient to meet the patient’s routine needs. But a good percentage of these patients have some degree of usable vision, which can be utilized for their day to day work using special aids or devices. If properly motivated, these patients can potentially benefit with the use of special aids or devices called ‘Low Vision Aids’. Tewari Eye Centre has a dedicated Low Vision Aids Service to help such patients.
Although most often experienced by the elderly, people of any age may suffer from low vision. Low vision can result from birth defects, inherited diseases, injuries, diabetes, glaucoma, high myopia and aging. The commonest cause is Age Related Macular Degeneration (ARMD), a degenerative disease of the retina, the innermost layer of the eye that perceives light and enables us to see. Macular degeneration affects the central vision. Even when advanced, it does not lead to total blindness because the peripheral vision is still preserved, even though the central vision may be totally lost. Although reduced central vision is the commonest cause of low vision, extensive loss of peripheral vision as in advanced glaucoma, can also produce low vision due to extremely narrow field of vision. Birth defects or inherited disease producing loss of color vision or increased glare sensitivity (diminished ability of the eye to adjust to light, contrast or glare) can also cause low vision.
Reduced central vision produces difficulty in reading, watching television and recognizing faces. Loss of peripheral vision reduces mobility. Increased glare sensitivity causes difficulty in driving. Impaired color vision results in difficulty in distinguishing different colors. Different types of low vision require rehabilitation with different kinds of ‘Low Vision Aids’.
A ‘Low Vision Aid’ (LVA) is a device or an apparatus that improves or enhances the residual vision in patients with low vision. There is no absolute level of vision above which LVAs will be useful, and below which they will not be. Also there is no one device that is suitable for all situations and all patients. Different devices are needed to fulfill the needs of various patients. Various low vision aids may need to be tried out before the most suitable device or devices is determined for a particular patient.
There are broadly two types of Low Vision Aids: Optical and Non-Optical.
Optical low vision aids use lenses, or a combination of lenses, to magnify the size of objects of regard at distance or near. The lowest magnification compatible with the task to be performed should be used by the patient. The main types of optical devices available are: Magnifying Spectacles – they have stronger, high-powered lenses compared to the usual eye glasses and are designed for close work. Patients using them need to hold the reading material very close to their eyes in order to keep the print in focus. One needs some practice to get used to these spectacles. They have the advantage of leaving both hands free to hold the reading material. The hands are also freed from holding a magnifying lens, an important consideration in old patients with shaky hands.
Hand Magnifiers – they are the most commonly used low vision devices. They offer greater flexibility because the patient can control their position in relation to the eye or the object of regard. Also, the reading material can be held at the normal distance. Some of them may have a self contained light source incorporated in them.
Stand Magnifiers have the magnifying lens mounted on a stand that rests on the reading material.
Sheet Magnifiers – these are essentially plastic sheets with concentric ridges on their surface. These are available as small size pocket magnifiers or large size book readers. However they provide only low magnification. Paperweight Magnifiers – they rest directly on the print material, which they magnify. Bar Magnifiers are useful for reading books or the telephone directory.
Telescopes – telescopes are aids to magnify distance objects. They may be hand held or mounted on spectacles. However they have the disadvantage of reducing the field of vision.
These include: – Large print books and magazines Large playing cards Large dial telephones Enlarging photocopiers Talking machines – talking watches, talking books, talking calculators, talking diaries & talking computers Closed circuit televisions – these can provide high magnification (up to 40 times) in an undistorted manner. The patient can get as close as he wishes to the monitor, which may be a small or a medium sized screen of a TV or a computer monitor. Contrary to popular belief, sitting close to the screen does not cause eye damage. Adjustable magnification and contrast make it easy to use.
Illumination has an important role in helping patients with low vision. Even for a normal person with advancing age, increased illumination is needed to perform the same task. Lighting should be ample, placed close to the reading material and be properly directed towards it. Illumination devices like high intensity reading lamps with adjustable arms are of good help. Visors and cap brims block the dazzling effect of overhead light. Glare control filters incorporated in the spectacles can help control glare and improve function in many patients.
At Tewari Eye Centre, a complete eye examination of patients with low vision is performed by ophthalmologists (medical doctors educated and trained to provide eye care). Total eye care to these patients starts with diagnosing the cause of low vision. Once the cause of low vision is determined, patients try out different low vision aids in a special low “Vision Aids Clinic”. According to the needs of the patient, the most suitable low vision device or devices are determined and then prescribed for him or her. Low Vision Aids assist many patients in leading a comfortable and relatively normal life. With these devices and proper motivation, people with visual loss can often read, do modified close-up work, and continue to take good care of themselves.