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Refractive errors- 3 marks



Refractive errors are a common type of vision problem that occur when the shape of the eye prevents light from focusing correctly on the retina. This can result in blurred vision or other visual disturbances. There are three main types of refractive errors:

Myopia: Also known as nearsightedness, myopia occurs when the eyeball is too long or the cornea is too curved, causing light to focus in front of the retina instead of directly on it. This can make distant objects appear blurry, while close objects appear clear.

Hyperopia: Also known as farsightedness, hyperopia occurs when the eyeball is too short or the cornea is too flat, causing light to focus behind the retina instead of directly on it. This can make close objects appear blurry, while distant objects may appear clear.

Astigmatism: Astigmatism occurs when the cornea is irregularly shaped, causing light to focus on multiple points on the retina instead of a single point. This can result in distorted or blurred vision, both up close and at a distance.

Refractive errors can be corrected with eyeglasses, contact lenses, or refractive surgery. Eyeglasses and contact lenses work by adjusting the way light enters the eye to correct the refractive error. Refractive surgery, such as LASIK, works by reshaping the cornea to correct the refractive error.

Regular eye exams are important for detecting and correcting refractive errors. If left untreated, refractive errors can lead to headaches, eye strain, and other vision problems.
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