Updated: January 17, 2018
A cataract is an eye disease in which the clear lens of the eye which lies behind the iris and the pupil becomes cloudy or opaque, causing a decrease in vision.
Cataracts mostly develop when aging or injury changes the tissue that makes up your eye's lens. The lens inside the eye works like a camera lens, focusing light onto the retina for clear vision. It also adjusts the focus of eye to view things clearly both up close and far away.
The lens is mostly made of water and protein. The protein is arranged in a such a way that keeps the lens clear and lets light pass through it. As we age, some of the protein may clump together and start to cloud a small area of the lens which forms a cataract and over time, it may grow larger and cloud more of the lens, making it harder to see.
Cataracts can also be caused by other eye conditions, past eye surgery or medical conditions such as diabetes. Long-term use of steroid medications can cause cataracts to develop. Some inherited genetic disorders that cause other health problems can increase your risk of cataracts.
All cataracts are a result of changes to the protein of the lens resulting in visual blurring or visual loss. Excessive exposure to ionizing radiation (X-ray), infrared radiation or ultraviolet radiation may also cause cataracts. Inflammatory disease of the eye, such as iritis or uveitis, may cause or accelerate the development of cataract in the affected eye.
Many genetic illnesses such as myotonic dystrophy, galactosemia, homocystinuria, Wilson's disease and Down syndrome are associated with the development of cataracts. Congenital infections with herpes simplex, rubella, toxoplasmosis, syphilis, and cytomegalic inclusion disease may also result in cataracts. Atopic dermatitis, other diseases of the skin and mucous membranes, hypothyroidism, and hyperparathyroidism are associated with the early development of cataracts.
Congenital cataract results because of genetic disorders or infectious or non-infectious intrauterine developmental disorders. In such cases the baby is born with clouding of the lens which may be present in one or both eyes, be stationary or be progressive. This is associated with other physical abnormalities of the baby. It is possible to develop cataracts in both eyes at an early age with family history.
Cataracts generally develop in both eyes, but not evenly. The cataract in one eye may be more advanced than the other, causing a difference in vision between eyes.
To prevent cataracts or slow the progression of cataracts the following things can be done:
Eye examinations can help detect cataracts and other eye problems at their earliest stages. Early detection of cataracts will help prevent its progression.
Medications, counseling and other strategies are available to help you quit smoking. This will reduce the risk of developing cataracts.
Follow your treatment plan if you have diabetes, hypertension or other medical conditions that can increase your risk of cataracts. Try to keep all parameters under control.
Ultraviolet light from the sun may contribute to the development of cataracts. Wear sunglasses that block ultraviolet B (UVB) rays when you are outdoors.
Excessive alcohol use can increase the risk of cataracts.
Adding a variety of colorful fruits and vegetables to your diet ensures that you are getting enough vitamins and nutrients. Fruits and vegetables have many antioxidants, which help maintain the health of your eyes. Fruits and vegetables contain many health benefits and are a safe way to increase the amount of minerals and vitamins in your diet which will help reduce risk of developing cataracts.
Sometimes a very dense cataract of long-standing duration may enlarge in size and interfere with fluid drainage within the eye. An advanced cataract may leak protein into the eye, causing inflammation of the eye. These complications can be avoided by surgery even if the decrease in vision is not bothering you.
Since the physician must look through the cataract to examine the retina, the evaluation of diseases of the retina is more difficult if there is presence of a cataract.