ASUHAN KEPERAWATAN

KATARAK

WHAT IS CATARACT?

A cataract is a condition that develops in the lens of the eye.

Cataracts are made from a protein that has altered from its natural

state (denaturation), distorting and eventually prohibiting required

light from entering into the retina, the part of the eye that receives

light

Often cataracts cause no problems for many years but as the cataracts

matures the cloudiness increases on the lens, the light reaching the

retina decreases and significant sight loss and perhaps blindness can

result.

ANATOMY OF A CATARACT

• Within the lens, cataracts can form in any of the three layers of the lens; the capsule, the cortex or the nucleus

• Cataracts which develop in the posterior subcapsular (PSC) area (in the rear region of the lens capsule) are most often associated with diabetes and are the ones most likely to be found in a younger age group. This type of cataracts has also been linked to the long term use of corticosteroids, inflammation of the eye or eye associated trauma.

• In contrast, cataracts found in the cortical or nuclear areas are usually age-associated although there is a much higher risk of developing cortical cataracts when the eyes have been exposed excessively to damaging UV rays of the sun.

STAGES OF CATARACTS:

1. ImmatureIf an individual still maintains part of

their vision, meaning the lens still has some clear

areas

2.mature A mature cataracts is one which is

entirely clouded over or opaque

3.Hypermature a hypermature cataracts has

begun to leak fluid from its hard outer capsule

which may lead to problems with adjacent areas

of the eye.

HYPERMATURE CATARACT MATURE CATARACT

RISK FACTORS

• In a majority of cases, cataracts form as individuals grow older. In fact, it has been suggested that by the time a person reaches 30 years old, the beginning stages of cataracts formation has already begun, although it may take up to another half a century for the cataracts to be fully developed and in need of medical intervention.

• Statistics show that by age 75, 70% of Americans may have cataracts which cause problems with everyday activities. Besides age, a second leading cause of cataracts is diabetes which is also the number one reason for blindness in adults between the ages of 20 and 74.

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• Other risk factors for the development of cataracts include lifestyle behaviors such as smoking and the excessive use of alcohol. Male smokers who go through 20 cigarettes or more per day have a two fold increase in their risk of developing cataracts and for women, smoking 35 cigarettes or more a day increases the risk by approximately one half. More than likely, smoking raises cataracts formation risk due to the higher quantity of free radicals floating around in a smoker's body. A second reason may relate to the inability of a smoker's body to shuttle enough nutrients to the lens where they are used for proper, routine maintenance. Over time, without the correct minerals and vitamins, the lens (especially the proteins of the lens) begins to deteriorate.

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Long term use of corticosteroids has come under attack for its relationship to cataracts occurrence, too. In one particular study, 80% of patients on a prolonged treatment regimen of oral prednisone of 15 mg a day went on to develop cataracts. In the past, it was thought that inhaled corticosteroids were safe to use, however, a recent study published findings of a 50% increase of nuclear cataracts and a 90% greater occurrence of posterior subcapsular cataracts in those patients using inhaled corticosteroids versus the group not using the steroids. This study is especially important for asthmatic patients to take into account if prescribed inhaled corticosteroids. In many cases, however, the benefit-risk ratio must be studied by both patient and doctor.

In a final note on corticosteroids, topical application to the eyelids and corticosteroid eye drops may also increase the risk of developing cataracts later in life.

Injuries to the eye, also known as traumatic cataracts formation, can occur from blunt or penetrating trauma as well as exposure to alkaline chemicals. Sometimes cataracts will develop soon after the trauma and in other cases may not show up until many years later. Prior eye surgery has also been shown to increase the risk of cataracts formation.

Those with a family history of cataracts run an increased risk of developing cataracts as do people that had developmental delays as a child, or were premature at birth. Being HIV positive, or of African-American heritage are both associated with a higher than normal risk of cataracts occurrence.

prolonged exposure to UV light from sunlight or even from x-rays, can increase the chance of cataracts formation. This type of cataracts is known as a radiation cataracts.

SYMPTOM

The most common symptom of cataracts is the noticeable blurring and worsening of vision. Other symptoms include the dimming and fading of colors, decreased night vision, problems with bright lights and sunshine, and in many cases, regular visits to the ophthalmologist for changes in glasses and contact lens prescriptions as vision worsens. Some patients report double vision in the affected eye although this symptom seems to decrease or disappear entirely as the cataracts grows.

How do Age-Related Cataracts Form?How do Age-Related Cataracts Form?

There are two major ways in which age-related cataracts form :

Protein clumping and yellowing of the lenses.

In the healthy eye, the lens is mainly made up of water and a

protein called crystallins. These proteins are thought to act

somewhat like filters allowing the light to enter into the eye and

become focused on the retina. There is little time for repair to the

lenses as they are in almost constant use. As an individual grows

older, some of the protein found in the lenses begins to

degenerate and clump, or gather, together. The gathering of this

material blocks some of the light that would normally enter

through the lens and hit the back of the eye, the retina. …………..CONT

A small amount of protein clumping may not affect the individual's vision noticeably. However, when enough protein clumps in one area, the amount of light entering the eye is decreased and the eyesight becomes progressively more blurry and cloudy. The majority of age-related cataracts are formed in this manner. The current theory is that the protein of the lenses is damaged by free radicals which in turn causes the proteins to clump. Free radicals can be neutralized with antioxidants but many people have too few of these in their bodies to control the free radical assaults. Antioxidants are found mainly in fresh fruits and vegetables.

The second method by which age-associated cataracts form is the result of a yellowing or browning of the normally clear, transparent lens. The discoloration of the lens is a common occurrence in most of the population as age increases and is usually the result of a breakdown of lens proteins which leave behind a yellow-brown pigment. The pigment tends to aggregate together and cloud the region of the lens.

Unfortunately, in some individuals the discoloration of the lens may cause everyday tasks to become more complicated. Those who suffer from cataracts of this type tend to lose the ability to distinguish the colors of blue and purple. This category of cataracts does not seem to cause blurring of shapes.

Some researchers have also pointed to the possibility that age-related cataracts may form due to low serum calcium levels. Nonetheless, in many cases, age-related cataracts have no identifiable cause.

TYPES OF CATARACTS

Depending on the cause of the cataracts development there are several types, other than age-related cataracts, which have been defined. They are secondary cataracts, traumatic cataracts, congenital cataracts and radiation cataracts.

Secondary cataracts can form following other eye problems. Examples include an eye that was previously treated for glaucoma or a different eye problem or disease. Health problems such as diabetes can also cause the formation of secondary cataracts. Additionally, the excessive or prolonged use of steroids, including medically approved steroids, has also been linked to the increased risk of secondary cataracts development.

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• In some individuals, cataracts may develop immediately or years after an event which causes damage to the eye. This is known as a traumatic cataracts and can occur due to blunt trauma to the eye or from exposure of the eye to alkaline chemicals. A penetrating eye injury is associated with quick cataracts development.

• If a child is born with a cataracts it is known as a congenital cataracts. In some cases this inherited condition may be insignificant enough to not interfere with vision, in which case it is left alone. If the cataracts does cause vision disturbances in the child the lens of the eye may be removed and replaced with a synthetic lens.

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The gene causing cataracts is dominant, meaning that the child need only inherit the gene from one parent to develop the condition. Other sources of congenital cataracts are specific illnesses or infections that the mother has during pregnancy. Rubella and its associated metabolic disorder, known as galactosemia, both increase the risk of having a child with a congenital cataracts. Additionally, children can develop cataracts at a young age from any number of other causes and these cataracts are also said to be congenital.

The final category of cataracts is radiation cataracts. This type of cataracts may be caused from over exposure to ultraviolet sunlight and other forms of radiation. Population studies have actually concluded that exposure to sunlight over a prolonged period of time could double the risk of cortical cataracts. Interestingly enough, cataracts which form in the nuclear area of the lens were not shown to increase in occurrence from UV exposure

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Moreover, patients who are taking any medication which causes skin sun sensitivity should be aware that the medication will more than likely also increases the sensitivity of the eyes to the sunlight. Drugs of this type include, but are not limited to, some antibiotics, allopurinol (used in the treatment of gout), psoralen drugs (used to treat vitiligo and T-cell lymphoma), and phenothiazine drugs (used for mental and emotional illnesses).

DIAGNOSIS

• During an eye exam, performed by an ophthalmologist or optometrist, there are several tests which may be administered to check for the presence of a cataracts.

• A visual acuity test will measure how well the individual can see while standing at various lengths from the cue card.

• A slip lamp exam uses a specialized microscope to increase the magnification of the eye. The specialist can then examine the eye in detail and up close.

• A tonometry test is a standard test which measures the fluid pressure inside the eye. The major finding in this test, if an increased pressure is detected, is the possibility of glaucoma.

• A dilated eye exam dilates the pupil. In this manner, the specialist is better able to view the lens to check for the present of a cataracts.

HOW TO PREVENTED??

• For starters, staying healthy and avoiding lifestyle habits that increase the risk of diabetes will subsequently decrease the risk of developing cataracts. Avoid environmental exposures which have been associated with cataracts formation such as prolonged use of corticosteroids, smoking and over-use of alcohol.

• To reduce the risk of radiation cataracts, wear sunglasses outside to protect the eyes from UV exposure. Choose sunglasses and eyeglasses which block out the harmful rays of the sun. This is especially true for children who do not understand the affect that over exposure to rays at a young age can have on their future eyesight. The Children's Memorial Hospital in Chicago now encourages parents to remind their children to wear sunglasses when they will be outdoors for longer than 20 minutes, especially if that time period falls during the hours of 10:00 am and 3:00 pm when the sun's rays are the strongest.

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• Pregnant females should be aware that if they contract German measles, also known as rubella, during pregnancy there is an increased risk of the child developing cataracts soon after birth. Therefore, some professionals recommend that women planning on having a baby ask their doctor for a rubella shot at least three months before becoming pregnant. This is an easy, but effective way to prevent cataracts in small children.

• A recent study published in the April 2004 edition of Trends in Molecular Medicine, suggest that calpain inhibitors may slow or even prevent the formation of age-associated cataracts. Calpains have been found to possibly be a major player in cataracts development by breaking down the essential proteins of the lens if left unchecked or unregulated. The possibility of a drug introduction which regulates or inhibits the activity of calpains could greatly decrease the risk of age-associated cataracts. 1

• In 2000, an article published in the American Journal of Clinical Nutrition show two Harvard performed studies which claim that when an individual's diet is high in lutein and zeaxanthin rich foods there is a 19 to 22 percent less chance of developing age-related cataracts than those who do not incorporate these foods into their diets in high quantities. Lutein and Zeaxanthin are phytochemicals, a naturally occurring group of biochemicals that are classified within the carotenoid class of molecules. Phytochemicals give plants their color, flavor, smell and texture.

• Foods which are high in lutein and zeaxanthin include green vegetables such as spinach, broccoli, collard greens, kale, mustard greens and peppers. Winter squash and eggs have also been found to contain high levels of these important cataracts preventing molecules.In fact, one study which compared the bioavailability of lutein in eggs, spinach and lutein supplements found that the highest rate of lutein which entered the bloodstream came after the consumption of eggs. 9 Researchers at Ohio State University have found evidence that lutein and zeaxanthin actually function to protect the eyes from the harmful effects of UV radiation, one of the risk factors associated with an increased chance of developing cataracts.

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• Virender Sodhi, a Medical Doctor and practicing Naturopathic doctor in Bellevue, Washington recommends a diet high in antioxidants both from food and supplemental sources to ward off the formation of cataracts. His suggestions include taking 600-800 IU of natural vitamin E, in the d-alpha tocopherol form, along with 1500 mg of vitamin C, 200 mcg of selenium and 25,000 IU of natural carotenoids daily. The carotenoids should be divided into three doses to be taken with meals. If the high dosage of Vitamin C causes loose stools, decrease the dosage. Add at least two servings of vegetables and fruits each day with the colors dark red, orange, yellow, blue and purple. With these suggestions, the diet will be very high in antioxidants, helping the body to fight off free radical damage, which can result in cataracts later in life. 5

• or those individuals who have diabetes, the risk of cataracts occurrence increases tremendously as do other eye related problems such as glaucoma. A study published in 2003 recommends several supplements which may help to prevent or at least delay the formation of cataracts in diabetics. After studying rabbit lenses in culture and the damaging effect that high blood sugar has on them, researchers concluded that supplementation with Vitamin B-6 (pyridoxine) and N-acetylcysteine (NAC), may help to decrease the oxidation of proteins; a step which causes the formation of free radicals and the increase in cataracts formation risk. 6