Cataract

Regular eye examinations after the age of 50 years are mandatory to detect eye diseases early and to institute timely treatment. Prevention of exposure to UV rays by regular use of UV protective sun glasses may confer certain degree of protection. However, any research or studies do not support this conjecture.

The word 'cataract' brings up a lot of anxiety, doubts, myths, queries and fear in the mind of the person aected by it, or his/her kin. This brochure aims to clear such doubts and myths and educate you about cataract and its current methods of treatment.

The first thing a person must do on experiencing any of these symptoms is to consult an Eye Surgeon (Ophthalmologist) for a thorough eye examination. Answers to the following questions should be sought:

• Do I have cataract?
• Do I have any other eye disease?
• What is the cause of cataract in my eye?
• What are the treatment modalities available?
• What treatment would be most suitable for me?
• What is the expected outcome of the surgery in my case?
• What are the risks involved and possible complications?
• How long can I wait before I get operated?
• What does the surgery involve in terms of time and expenditure?

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. Exposure to ultra-violet light has definite role in the formation of cataract.

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 
• Colours seem faded 
• Double or multiple vision (this symptom goes away as the cataract grows) 
• Frequent changes in eye glasses or contact lenses

These symptoms can also be a sign of other eye problems. In the event of any of these symptoms please consult an eye surgeon. In early cataract one may not notice any changes in vision. Cataract tends to grow slowly, so vision worsens gradually. Some people with a cataract find that their near vision suddenly improves (phenomenon of second-sight), but this is temporary. Vision is likely to get worse again as the cataract grows.

Age-related cataract: Most cataracts are related to aging.

Congenital cataract: Some babies are born with cataracts or develop them in childhood, often in both eyes. These cataracts may not affect vision. If they do, they may need to be removed.

Secondary cataract: Cataracts are more likely to develop in people who have certain other health problems, such as diabetes. Also, cataracts are sometimes linked to steroid use.

Traumatic cataract: Cataracts can develop soon after an eye injury, or years later.

A comprehensive eye examination usually includes:

Visual acuity test: This eye chart test measures how well you can see at various distances.

Pupil dilation: The pupil is widened with eye-drops to allow us to see more of the retina and look for other eye problems.

Tonometry: This is a standard test to measure eye pressure. Increased pressure may cause glaucoma.

Ultrasound (Biometry) of the eye to calculate the power of the lens to be implanted. Other eye and general test may be required to establish complete diagnosis and fitness for cataract surgery.

Currently, phacoemulsification with a foldable intraocular lens implantation through a 3 mm incision is the most preferred method of cataract surgery and has the best results, all over the world. Other types of operations are performed in special circumstances.

Currently, lasers are not commonly used to remove cataract (although some patients mistakenly use the term Laser for Phacoemulsification). Research is under way to use lasers-Dodick in cataract surgery and some success has been reported.