Hypermetropia Research Paper

Hypermetropia is the opposite of myopia and it is also known as hyperopia. It can be described as “the eye … being too weak for its length, or as being too short for its power.” – (Atchison & Smith, 2000). It is also measured in dioptres. More severe cases of hypermetropia include not being able to see objects clearly at a distance as well as objects in up close. Hypermetropia can occur at any age but it tends to be more common in ages 40 years and above. It usually worsens with ages due to loss of accommodation in the eye, the ability of the lens to change its shape to form a clear image. Babies and young children can develop hypermetropia but usually only a slight case which they tend to grow out of by the age of 3 years. Like myopia, hypermetropia

Astigmatism

Astigmatism is a condition where the eye’s reflecting surfaces have an uneven curvature. It is generally the cornea that has the uneven surface as it is not perfectly spherical but has a slight curve. Astigmatism occurs when this curve is too great so when light passes through the cornea and the lens, it is not focused correctly on the retina which causes the image to be blurred. Astigmatism can be corrected with cylindrical lenses called toric

It is the loss of accommodative ability of the lens from 15 dioptres in early childhood to 1 dioptres before the age of 65. This results in difficulty carrying out nearby tasks. It is similar to hypermetropia but it occurs with age. Presbyopia occurs because the lens becomes thicker and hardens with age and therefore loses flexibility. These changes occur in the proteins in the lens which is what causes it to become less elastic over time. Because the lens has less elasticity, this makes it harder for the eye to focus on objects at a close distance. Presbyopia usually begins to occur around the age of 40 years and continues to worsen until the age of 65. Accommodation is completely lost in the 50s. Once presbyopia occurs, it cannot be slowed down or reversed but it is treatable. Presbyopia can be treated with positive lens or convex lens. These include bifocals, which correct near and far vision, trifocals, which correct near, middle, and far vision, and progressive lens, which change the magnifying power from near to middle to far vision gradually. Presbyopia can be classified by