Refractive Errors are common visual problems that result in blurred vision. Myopia (nearsightedness), hyperopia (farsightedness), astigmatism and presbyopia are the different types of refractive error.
Refraction is the bending of light as it passes through one object to another. Vision occurs when light rays are bent (refracted) as they pass through the cornea and the lens. The light is then focused onto the retina. The retina converts light-rays into messages that are sent through the optic nerve to the brain. The brain interprets these messages into the images we see.
Who Gets Refractive Errors?
Refractive errors can affect both children and adults. However its important to detect refractive error in children so as to avoid the development of lazy eyes.
Individuals that have parents with certain refractive errors may be more likely to get one or more refractive errors.
SYMPTOMS AND SIGNS
Blurred vision is the most common symptom of refractive errors. Other symptoms may include:
- Double vision
- Glare or halos around bright lights
- Eye strain
- Poor night vision
TYPES OF REFRACTIVE ERRORS
is a condition where objects up close appear clearly, while objects far away appear blurry. With myopia, light comes to focus in front of the retina instead of on the retina.
is a common type of refractive error where distant objects may be seen more clearly than near objects. However, people experience hyperopia differently. Some people may not notice any problems with their vision, especially when they are young. For people with significant hyperopia, vision can be blurry for objects both near and far.
is a condition in which the eye does not focus light evenly onto the retina, the light-sensitive tissue at the back of the eye. This can cause images to appear blurry and stretched out.
starts to affect most adults over age 35, when they progressively find difficulty focussing at near distance. This often impacts on activities like reading and knitting. This happens when the natural lens gradually looses its elasticity. It’s this elasticity that permits multifocality in the eyes of the younger individual.
Eyeglasses are a simple and safe way to correct refractive errors.
You can visit the optician or optometrist to get your eyes checked and be prescribed a pair of eyeglasses.
Contact lenses work by becoming the first refractive surface for light rays entering the eye, resulting in a more precise refraction or focus. In many cases, contact lenses provide clearer vision, a wider field of vision, and greater comfort. They are a safe and effective option if fitted and used properly. To know your suitability of contact lens wear, the cornea curvature, ocular health and lens fitting must be assessed by the optometrist.