Cataracts Essay Sample

A cataract refers to an eye disorder causing the eye’s lens to become opaque and cloudy, thus reducing vision. The lens is the clear part that helps to focus the incoming light rays onto the retina, which is sensitive to light and located at the back of the eye. In order to function properly, the parts in front of the retina must be transparent to allow a sharp image to fall on the retina (Andrew, 2000). For clear resolution by the eye, all parts must coordinate appropriately so that the electrical response carried to the brain can be clearly interpreted. When an eye is suffering from cataracts, the lens is cloudy, and the image that falls on the retina is blurred, causing poor resolution and vision. The extent to which vision is blurred depends on the degree of cloudiness occurring in the lens. Cataracts show symptoms of reduced vision, and the affected eye appears whiter than normal. The treatment of cataracts depends on the visual requirements of every patient and sometimes may extend to surgery level. Most cases of cataracts have been related to aging, although other causes are possible. The disorder is more common in the elderly, and statistics have proven that by the age of 80, more than 40% suffer from cataracts, with the condition worsening. A cataract may occur on either one of the eye or both (Andrew, 2000). Though the disorder is not contagious, individuals suffering from cataracts in one eye have a high chance of developing it in the other eye. Cataracts do not cause unusual tearing in the eye, and the disorder is also not painful or itchy. Among the elderly, the disorder can cause blindness if not treated promptly and with proper instruments. Cataracts can be classified into several types depending on their location in the lens. These include Lenticular, Capsular, and Capsulo-lenticular cataracts, which may be either imperfect or confined to a portion of the eye. The extent of clouding on the lens also varies by its cause. Capsular opacity in the eye does not start in the center but at the membrane margin, sometimes proceeding regularly towards the center, forming a shiny satin appearance.  In other cases, it may spread irregularly over the membrane surface causing a dull white opacity that is unequal in intensity. The human eye lens is round shaped and it has both the front part (anterior) and a back part (posterior) (Andrew, 2000). The central part of the lens is known as the nucleus, and the outer part is the capsule. Between nucleus and the capsule lies another lens part, the cortex. Clouding of the eye lens may happen in the nucleus only and it is termed as nuclear cataract. In situations where clouding occurs in the cortex only, it is known as a cortical cataract. If the clarity loss of the lens occurs predominantly in the capsule, it is termed as subcapsular cataract. The clouding location on the lens is also referred to as posterior or anterior, peripheral or central. It is also possible for the clouding to affect different portions simultaneously on the lens. Cataracts that are age related are referred to as senile and that affecting younger people mostly occurs in the posterior subcapsular. The degree of opacity of the lens defines the extent of the cataract as either mature or immature (Andrew, 2000). The lens is comprised mostly of protein and water. The proteins are aligned in a specific manner keeping the lens clear and allowing light to penetrate such that a clear image is focused onto the retinal surface. Due to aging, some protein ends up clumping together clouding a small region of the lens. Continued clouding of the proteins on the lens makes it harder to see. Also opacity of the lens may occur due to inflammation which may arise from wounds on the lens hindering the transparency that is required for a clear image to be observed. Cataracts as a result of an injury may appear and may not increase in intensity (William, 2010). Inflammation of the lens may also occur without resulting from wounds or injuries, leading to partial or complete opacity. Cerebral vessels, mainly those of the eye globe, may also become congested, which is a possible cause of cataracts. Secondary cataracts may also result from changing the protein of the lens, resulting in visual blurredness or complete visual loss. Surgery of the eye resulting from other conditions is a possible cause for cataracts. Exposure to ionizing radiation exemplified by X-rays and infrared radiations excessively can also lead to secondary cataracts (Andrew, 2000). Persons suffering from diabetes are more predisposed to secondary cataracts. This is also associated with eye inflammatory disorders like Iritis and Uveitis, which can result in or speed up cataract development in the eye involved. Also, there are genetic diseases that are associated with secondary cataract development and include the myotonic dystriophy, homocystinuria downsyndrome among others (William, 2010). Some medications, commonly used for a wide variety of conditions, when taken for a long time, may result in secondary cataracts. It is possible for a baby to be born with clouding in the lens in one or both eyes. This can be genetically transferred or disorders acquired during intrauterine development of the baby. Some skin diseases and membrane mucous are related with occurrence and development of cataracts.

Dimness of vision is among the initial symptoms experienced by someone suffering from cataracts. This is characterized by misty and clouded figures at advanced stages. Others perceive distant objects more clearly than those that are close, though this is commonly attributed to advancing years and might change. The changes in symptoms over time are associated with opacity originating from the center of the lens, such that when the pupil contracts. It becomes more blocked by the opaque material, while if dilated, light rays will still pass through the transparent small circumference part that enhances resolution (Scott, 2005). Normally, it is difficult to notice the early symptoms of cataracts. As the condition becomes intense and advanced, the clarity decreases and may exceed levels correctable by glasses. Loss of sensitivity to contrast where one observes a color being less vivid is a sign in the advanced stage.  Scattering of light in the eye may lead to observing an uncomfortable glare. Cataracts may form without experiencing other diseases in the eye; hence, one is unable to notice any symptoms. This allows the disorder to progress without detection until vision is impaired (Scott, 2005). Loss of capability to judge distances is a common symptom and is commonly experienced when one eye is adversely affected, affecting vision (Andrew, 2000). Some types of cataracts cause objects to appear distorted, twisted, and irregular.  However severe a cataract is, it should not encumber one from sensing light rays as opposed to total blindness. One can always distinguish light from darkness and can sense when something opaque is passed through. Cataracts however do not cause disturbances or alter the structure of the eye. People closely and frequently interacting with someone suffering from cataracts in both eyes may notice that the person appears to have unusual behavior in observation or is not seeing as well as before. To a new person or an untrained observer, it is difficult to notice unless the condition has reached a mature level, or the eye appears white. In such circumstances, the pupil which normally appears to be black, will seem white or grey the observer (William, 2010). In diagnosing different forms of cataracts, physicians trained in examining such conditions can detect visually diminished acuity in the affected eye or eyes. In a striated cataract, a patient’s vision is never improved by any form of pupil dilation. This is due to the fact that, the disorder originates from the from the edges instead of starting from the center of the lens thus making its margin most blocked from light and hence fail to transmit light rays as compared to the center. During the initial stage, the hard lenticular cataract causes opacity to be concentrated in the central region of the lens, which appears greyish in color and seems to lie deeper than normal due to the lens surface retaining transparency. When both the lens and the capsule are opaque, the base of the opacity reflects light rays from the surface. This causes a shiny, satin-like, and irregularly opaque appearance. This can also be described as chalk-like, though its transparency is not completely lost and can allow the color of the lens to be identified (Scott, 2005). In glaucoma, the mobility of the pupils is significantly impaired, if not completely.  In its early stage, the deeply seated opacity is usually limited to a small spot that appears to shift its location depending on the direction of admitted light rays into the eye. In this condition the patients is more comfortable observing in stronger light as compared to weak light rays and upon usage of a belladonna his vision becomes more impaired instead of being improved. In the advanced stage, the condition causes the pupil to become motionless, dilated, and irregular. A characteristic opaque lens that is protruding outwards pressing the iris is observed (William, 2010). A soft cataract is characterized by uniformity in occurrence, being of lighter color than other forms, and completing coverage of the eye in a much shorter time. It commonly occurs at an early age, unlike hard cataracts. It causes an excessively opaque margin that obscures vision, even where the pupil has been dilated. The loss of visual capability may not be fully corrected by a change in the glasses used. An ophthalmologist has the capability to easily examine the alterations in the lens characterized by cataracts using specially designed equipment known as the slit lamp. Usage of sunglasses and increased lighting for people with early stages of cataracts may lead to alleviated condition. A patient may also be advised to use magnifying lens for reading fine prints. Cataracts can only be treated through surgery, and this depends on the visual needs for specific patients (Andrew, 2000). Cataracts vary in symptoms and characteristics among different patients. The modes of treatment also vary as the forms of cataracts vary. Cataracts do not harm the eye and surgery should be carried out after a patient fully understands the benefits and the risks involved. If an eye suffers from other diseases causing visual impairment, cataract surgery may not improve vision. n a situation where both eyes suffer from cataract and have to be operated, the second eye is operated after at least a week-long period after the first operation (William, 2010). Before an operation is carried out, an artificial lens with features exactly matching those of a natural one is necessary and should be ordered in advance. There are no known preventive measures that can prevent the development of cataracts.

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