EYEGLASSES AND CONTACT LENSES (Part I) By Dr Chris Galadima While many are buying all types of Eyewear from the general market place and street corners without any informed guide or prescription others are hesitant about using glasses even when prescribed by an Ophthalmologist or an Optometrist. Here is some information that will help you understand Eyewear better and possibly help you to understand and discard some commonly held myths about Eyewear. Eyewear is any accessory worn over or on the eyes usually to enhance vision, but also for protection, fashion and adornment. Eye wear can either be Eyeglasses (aka Spectacles or Glasses), Sunglasses, Goggles or Contact Lenses. EYEGLASSES Eyeglasses are the most commonly used Eyewear; they consist of frames that bear lenses and are worn in front of the eyes either to enhance vision, for protection, for fashion or for a combination of these reasons. Frames are a major determinant of the cost of Eyeglasses. They come in wide variety of designs, shapes and sizes; there are full-rimmed, half-rimmed and rimless designs. The materials with which frames are made also vary a great deal; from precious materials like gold, ivory, tortoise shell to plastic and other metals. A combination of different materials in frame design is also common. Frames are a huge issue in the fashion industry; with many fashion and other business giants having big investment in the production of frames. Brands such as Gucci, Versace, Ferrari, Mont Blanc, Prada etc are some of such heavy investors. Frames of eyeglasses are commonly attached to the Personal Image of wearers; Most people can hardly imagine the face of Chief Obafemi Awolowo or Dr Nnamdi Azikiwe without their eyeglasses. The material used for the lenses in eyeglasses is usually Glass, but recently Plastic material is more commonly used because of its better optical properties, lighter weight, better protection against ultraviolet radiation and lesser tendency to shatter when violently impacted. Although Plastic material is scratched easier than Glass, there are scratch resistant coatings used in most plastic lenses available today. Hydrophobic and anti-reflective coatings are also used to improve the quality of plastic materials used in making of lenses. The power of glasses used in prescribed spectacles is usually determined by an eye specialist; usually an Ophthalmologist (a medical doctor who specializes in the diagnosis and treatment of eye disorders) or an Optometrist (a person trained to detect and treat refractive errors), in a procedure called Refraction. The eyeglasses are then produced in an Optical laboratory by an Optician. The types of refractive errors that eyeglasses are used to correct include: Myopia (Shortsightedness, Nearsightedness): in which there is difficulty in seeing distant objects clearly. Hyperopia (Farsightedness, Hypermetropia): commonly thought as difficulty in seeing near objects clearly, but in fact, sufferers have difficulty in seeing both near and distant objects clearly. Astigmatism: a distortion of vision caused by defect in the curvature of the cornea. Presbyopia: Age related decrease in ability to focus on near objects like small prints in a book, computer or cell phone. Prescribed Eyeglasses are often called ‘Medicated Glasses’, this name has made many people view glasses as containing medication to treat eye disease; this is a very wrong view. All that Eyeglasses do is to change the direction of light as it passes through the lenses before it enters the eye and therefore helps the eye to focus images on the retina with ease for clearer vision. Some people also fear that Eyeglasses weakens the eyes, but this fear is founded on a wrong assumption. Some people have eye disorders that are progressive in nature e.g High Myopia, Presbyopia requiring change of power of eyeglasses used with time. This requirement of change of glasses is due to the progressive nature of the disorder not due to any effect of glasses on the eye. Some young persons also feel that Eyeglasses make people look old, this view is not unrelated to the fact that in the past elderly people often had cataract operations and were given very thick and cosmetically unappealing glasses, so this ugly glasses became associated with age. Thankfully, this form of cataract operation is obsolete and very few people ever get this type glasses nowadays. Glasses are now used, not only to improve vision, but to make fashion statements, build personal image and identity by people of all ages and class. While there is nothing wrong with the use of Eyeglasses for all the reasons mentioned, those who require glasses for correction or improvement of vision do well to always get to see an eye care specialist before obtaining a pair of Eyeglasses...not only will the most appropriate glasses be obtained, but some undetected eye condition could be found and treated before it is too late.
Posted on: Sun, 28 Jul 2013 08:26:45 +0000