Cataract

What is the lens? What is a cataract? What causes cataract? What are the different types of cataract! How is it treated? What are the symptoms? How is cataract detected? Cataract Surgery!
What is the lens? The lens is the part of the eye that helps focus light on the retina. The retina is the eye's light-sensitive layer that sends visual signals to the brain. In a normal eye, light passes through the lens and gets focused on the retina. To help produce a sharp image, the lens must remain clear. Back to Top What is a cataract? The lens is made mostly of water and protein. The protein is arranged to let light pass through and focus on the retina. Sometimes some of the protein clumps together and starts to cloud a small area of the lens. This is a cataract. Over time, the cataract may grow larger and cloud more of the lens, making it hard to see. Although researchers are learning more about cataracts, no one knows for sure what causes them. Scientists think there may be several causes, including smoking and diabetes. Or, it may be that the protein in the lens just changes as it ages. There is also some evidence that cataracts are linked to certain vitamins and minerals. The National Eye Institute (NEI) is doing a study to see whether taking more of these substances prevents or delays cataracts. Scientists do know that a cataract won't spread from one eye to the other, although many people develop cataracts in both eyes. Back to Top What causes cataract? A cataract is a cloudy area in the lens of the eye that interferes with normal vision. Although scientists do not know what biological mechanisms are responsible for the formation of cataracts, they have identified several risk factors for the condition. Risk Factors *Ultraviolet Radiation (UVA or UVB)* - long-term exposure to ultraviolet radiation can result in pigment changes that lead to the formation of cataracts. UVB is especially dangerous to the eyes. *Free Radicals* - high levels of free radicals within the body cause a chemical reaction that results in cell damage. This can lead to the formation of cataracts. Medications - there are several drugs that can lead to cataract formation. The most well known are oral steroids. In addition, long-term aspirin use has been associated with cataracts. Other medications that have been linked to cataracts include: tamoxifen (treats breast cancer), allopurinol (treats gout), and amiodarone (treats irregularities in heartbeat). Smoking - smoking has been linked to the formation of nuclear cataracts. There is some evidence to suggest that chemical byproducts of inhaled smoke are responsible for cataract formation. Alcohol - scientists have been unable to determine if alcohol use is directly linked to the protein on the eye, or if it is linked indirectly by blocking the absorption of essential nutrients. Medical Disorders - there are several medical disorders that have been associated with the formation of cataracts. These include diabetes, glaucoma, and metabolic conditions. Physical Injury - physical injuries, such as a blow to the eye, a cut, a puncture, intense heat or cold, chemical burns, or radiation therapy, can lead to cataract formation. Back to Top What are the symptoms? The most common symptoms of a cataract are: Cloudy or blurry vision. Problems with light, such as headlights that seem too bright at night, glare from lamps or the sun, or a halo or haze around lights. - Colors that seem faded. - Double or multiple vision (this symptom goes away as the cataract grows). - Frequent changes in your eyeglasses or contact lenses. - These symptoms can also be a sign of other eye problems.If you have any of these symptoms, check with your eye care professional. Back to Top
Normal vision	The same scene as it might be viewed by a person with cataracts.
When a cataract is small, you may not notice any changes in your vision. Cataracts tend to grow slowly, so vision gets worse gradually. Some people with a cataract find that their close-up vision suddenly improves, but this is temporary. Vision is likely to get worse again as the cataract grows. Back to Top What are the different types of cataract? According to the National Eye Institute, part of the National Institutes of Health, cataract types are subdivided accordingly: Age-related Cataracts The majority of cataracts are related to aging. Congenital Cataracts Some babies are born with cataracts or develop them in childhood, often in both eyes. Some congenital cataracts do not affect vision, but others do and need to be removed. Secondary Cataracts Secondary cataracts develop primarily as a result of another disease occurrence in the body (i.e., diabetes). Secondary cataract development has also been linked to steroid use. Traumatic Cataracts Eye(s) that have sustained an injury may develop a traumatic cataract either immediately following the incident, or several years later. Nuclear Cataract This is the most common type of cataract, and the most common type associated with aging. Nuclear cataracts develop in the center of the lens and can induce myopia, or nearsightedness -- a temporary improvement in reading vision which is sometimes referred to as "second sight." Unfortunately, "second sight" disappears as the cataract grows. Cortical Cataract This type of cataract initially develops as wedge-shaped spokes in the cortex of the lens, with the spokes extending from the outside of the lens to the center. When these spokes reach the center of the lens they interfere with the transmission of light and cause glare and loss of contrast. This type of cataract is frequently developed in persons with diabetes, and while it usually develops slowly, it may impair both distance and near vision so significantly that surgery is often suggested at an early stage. Subcapsular Cataract A subcapsular cataract usually starts as a small opacity under the capsule, at the back of the lens. This type of cataract develops slowly and significant symptoms may not occur until the cataract is well developed. A subcapsular cataract is often found in persons with diabetes, myopia, retinitis pigmentosa, and in those taking steroids. Back to Top How is cataract detected? To detect a cataract, an eye care professional examines the lens. A comprehensive eye examination usually includes: Visual acuity test: This eye chart test measures how well you see at various distances. Pupil dilation: The pupil is widened with eyedrops to allow your eye care professional to see more of the retina and look for other eye problems. Tonometry: This is a standard test to measure fluid pressure inside the eye. Increased pressure may be a sign of glaucoma. Your eye care professional may also do other tests to learn more about the structure and health of your eye. Back to Top How is it treated? For an early cataract, different eyeglasses, magnifying lenses, or stronger lighting may improve vision. If these measures don't help, surgery is the only effective treatment. The surgeon removes the cloudy lens and replaces it with a substitute lens. A cataract needs to be removed only if it affects your vision so much that it interferes with your daily activities. You make that decision. If you decide on surgery, your eye care professional may refer you to another specialist to remove the cataract. If you have cataracts in both eyes, the surgeon will not remove them both at the same time. You will need to have each done separately. Sometimes, a cataract should be removed even if it doesn't bother you. For example, if it prevents examination or treatment of another eye problem such as age-related macular degeneration or diabetic retinopathy, a cataract should be treated. Back to Top Cataract Surgery If you've chosen to have surgery, it's helpful to know more about it. This section describes the types of cataract surgery, lens substitutes, and what you can expect before and after surgery. Is cataract surgery effective? Cataract removal is one of the most common operations performed in the Jordan today. It is also one of the safest and most effective. More than 90 percent of people who have cataract surgery have better vision afterward. However, even with the best results, your vision may not be as good as before the cataract. Back to Top How is a cataract removed? Phtolysis Almost everyone develops cataracts as they age. The cloudy or opaque areas on the normally transparent lens of the eye can lead to blurred vision, sensitivity to light and glare, increased nearsightedness or distorted images. The new Dodick System is the first laser system approved by the FDA for the removal of cataracts. During the surgery, a physician makes two tiny incisions - nearly half the size used in traditional cataract surgery. This technique promotes faster healing. The 10-minute procedure removes the cloudy lens and replaces it with a new artificial lens, and the patient can return home immediately with no stitches or eye patches. Phacormulsification: Phacoemulsification ("phaco") was developed in the search for a way to extract cataracts through a smaller incision. It has become the preferred technique for cataract extraction. An ultrasound or laser probe is used to break the lens apart without harming the capsule. These fragments are then aspirated out of the eye. A foldable intraocular lens (IOL) is then introduced through the 3mm incision. Once inside the eye, the lens unfolds to take position inside the capsule. No sutures are needed, as the incision is self-sealing. The risk of astigmatism and sudden pressure changes inside the eye are minimized. The procedure is safe enough to be done under topical anesthesia (anesthetic eyedrops). Visual rehabilitation is extremely fast and patients don't need to suspend their everyday activities. Extracapsular Extraction: This is a rather old technique in which a 12mm incision is performed in the eye to extract the lens as a whole. The lens' capsule is left in place to hold an intraocular lens. Multiple sutures are required to seal the eye after surgery. These sutures must be carefully tightened not to produce astigmatism. Back to Top

Risk Factors