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Eye Care Information

Refractive errors

Normal Eye Light rays from distant object come to a sharp focus on retina.

Myopia Nearsightedness, or myopia, as it is medically termed, is a vision condition in which close objects are seen clearly, but objects farther away appear blurred. Nearsightedness occurs if the eyeball is too long or the cornea, the clear front cover of the eye, has too much curvature. As a result, the light entering the eye isn’t focused correctly and distant objects look blurred.

Generally, nearsightedness first occurs in school-age children. Because the eye continues to grow during childhood, it typically progresses until about age 20. However, nearsightedness may also develop in adults due to visual stress or health conditions such as diabetes. A common sign of nearsightedness is difficulty with the clarity of distant objects like a movie or TV screen or the chalkboard in school.

Hypermetropia Farsightedness, or hyperopia, or hypermetropia as it is medically termed, is a vision condition in which distant objects are usually seen clearly, but close ones do not come into proper focus. Farsightedness occurs if your eyeball is too short or the cornea has too little curvature, so light entering your eye is not focused correctly. Common signs of farsightedness include difficulty in concentrating and maintaining a clear focus on near objects, eye strain, fatigue and/or headaches after close work, aching or burning eyes, irritability or nervousness after sustained concentration.

Common vision screenings, often done in schools, are generally ineffective in detecting farsightedness. A comprehensive optometric examination will include testing for farsightedness.

Astigmatism Astigmatism is a vision condition that causes blurred vision due either to the irregular shape of the cornea, the clear front cover of the eye, or sometimes the curvature of the lens inside the eye. An irregular shaped cornea or lens prevents light from focusing properly on the retina, the light sensitive surface at the back of the eye. As a result, vision becomes blurred at any distance. Astigmatism is a very common vision condition. Most people have some degree of astigmatism.

Slight amounts of astigmatism usually don't affect vision and don't require treatment. However, larger amounts cause distorted or blurred vision, eye discomfort and headaches. Astigmatism frequently occurs with other vision conditions like nearsightedness (myopia) and farsightedness (hyperopia). Together these vision conditions are referred to as refractive errors because they affect how the eyes bend or "refract" light. The specific cause of astigmatism is unknown. It can be hereditary and is usually present from birth. It can change as a child grows and may decrease or worsen over time.

A comprehensive optometric examination will include testing for your refractive condition. An optometrist can prescribe eyeglasses or contact lenses or other devices that correct the light rays that enter the eyes, ensuring correct focusing of the images correctly at the back of the eye.

Presbyopia is a vision condition in which the eye loses its ability, to focus on close objects. This is a natural ageing process but becomes noticeable around the age of 40. It cannot be prevented. Some of the signs of presbyopia include the tendency to hold reading materials at arm's length and eye fatigue especially in dim illumination or when doing close work.

There are various options to correct presbyopia. Some of the common ones are reading glasses, bifocals, trifocals, progressive lenses or contact lenses. An Optometrist will understand your hobbies and profession to prescribe the most suitable corrective devices.