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Eye disease - Cataract

Cataract surgery facts

Early symptoms of cataracts includeblurred vision, glare, and difficulty reading.
Cataracts will affect most people and become more prominent as we age.
Cataracts can be diagnosed when the doctor examines the eyes with specialized viewing instruments.
The decision to proceed with surgery is primarily based on the amount of difficulty you have performing your routine daily activities.
Treatment for cataracts is surgical removal of the cataract with implantation of an artificial lens.
There are a variety of intraocular lenstypes that can restore vision in different ways.
Cataract surgery is a safe and effective way to restore vision with serious complications being unusual.

What is a cataract?

A cataract is an eye disease in which the normally clear lens of the eye becomes cloudy or opaque, causing a decrease in vision. The lens focuses light onto the back of the eye (the retina) so images appear clear and without distortion. The clouding of this lens during cataract formation distorts vision. Cataracts are usually a very gradual process of normalaging but can occasionally develop rapidly. They commonly affect both eyes, but it is not uncommon for a cataract in one eye to advance more rapidly. Cataracts are very common, especially among the elderly.

Precisely why cataracts occur is unknown. However, most cataracts appear to be caused by changes in the protein structures within the lens that occur over many years and cause the lens to become cloudy. Rarely, cataracts can present at birth or in early childhood as a result of hereditary enzyme defects, other genetic disease, or systemic congenital infections. Severe trauma to the eye, eye surgery, orintraocular inflammation can also cause cataracts to develop more rapidly. Other factors that may lead to development of cataracts at an earlier age include excessive ultraviolet light exposure, exposure to ionizing radiation, diabetes,smoking, or the use of certain medications, such as oral, topical, or inhaled steroids. Other medications that may be associated with cataracts include the long-term use of statins and phenothiazines.

The total number of people who have cataracts is estimated to increase to 30.1 million by 2020. When people develop cataracts, they begin to have difficulty doing activities they enjoy. Some of the most common complaints include difficulty driving at night, reading, or traveling. These are all activities for which clear vision is essential.

What are the symptoms and signs of cataracts?

Cataract development is like looking through a dirty windshield of a car or smearing grease over the lens of a camera. Cataracts may cause a variety of complaints and visual changes, including blurred vision, difficulty with glare (often with bright sun or automobile headlights while driving at night), dull color vision, increased nearsightednessaccompanied by frequent changes in eyeglass prescription, and occasionally,double vision in one eye. A change in glasses may initially help once vision begins to change from a cataract. However, as the cataract continues to become denser, vision also becomes more cloudy, and stronger glasses or contact lenses will no longer improve sight.

Cataracts typically develop gradually and are usually not painful or associated with any eye redness or other symptoms unless they become extremely advanced. Rapid and/or painful changes in vision raise suspicion for other eye diseases and should be evaluated by an eye-care professional.

How are cataracts diagnosed?

Cataracts are detected by finding lens opacification during a medical eye examination by an eye-care professional. The abnormal lens can be seen using a variety of specialized viewing instruments. Using a variety of tests, a doctor is able to tell how much a cataract may be affecting vision. Usual eye tests include testing visual acuity, glare sensitivity, color vision, contrast sensitivity, and a thorough examination of all other parts of the eye. A thorough eye examination will make surevision loss is not due to other commoneye problems, including diabetes,glaucoma, or macular degeneration.

Most cataracts associated with agingdevelop slowly, and many patients may not notice visual loss until it is fairly advanced. It is not imperative to have surgery to remove them until they begin to affect vision. The development of cataracts is unpredictable; some cataracts remain less dense and never progress to the point where they cause cloudy vision and require treatment, while others progress more quickly. Thus, the decision and timing to proceed with cataract surgery is individualized for each patient. Your doctor will be able to tell you how much of your vision loss is due to cataracts and the type of visual recovery that may be expected if surgery is chosen.

Who is a candidate for cataract surgery?

Eye-care professionals may mention during a routine eye exam that you have early cataract development even if you are not yet experiencing visual symptoms. Although your doctor will be able to tell when you first begin to develop cataracts, you will generally be the first person to notice changes in your vision that may require cataract surgery. Clouding of the lens may start to be seen at any age, but it is uncommon before the age of 40. However, a large majority of people will not begin to have symptoms from their cataracts until many years after they begin to develop. Cataracts can be safely observed without treatment until you notice changes in your vision.

Surgery is recommended for most individuals who have significant vision loss and are symptomatic secondary to cataract. If you have significant other eye disease unrelated to cataracts that limits your vision, your ophthalmologist may not recommend surgery. Sometimes after trauma to the eye or previous eye surgery, a cataract may make it difficult for your eye-care professional to see the retina at the back of the eye. In these cases, it may still be appropriate to remove the cataract so that further retinal or optic nerveevaluation and treatment can occur. The mode of surgery can be tailored to individuals based on coexisting medical problems. Cataract surgery is generally performed with minimal sedation and typically takes less than 30 minutes. Therefore the surgery does not put significant strain on the heart or thelungs.

Prior refractive surgery such as LASIK is not a contraindication to cataract surgery.

A cataract is a medical condition, and insurance companies usually cover part or all of the cost of cataract surgery, including pre- and postoperative care. Ask your physician any questions you may have about the cost involved.

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