SNEC Explains: Cataracts

Problems seeing due to cloudy vision that even spectacles cannot help? You could have a cataract, a cloudy growth on your eye.

What is a cataract?

Cataract is a condition in which the clear lens of the eye becomes cloudy, preventing sufficient light rays from entering the eye and impairing vision.

What causes cataract?

It is common in the elderly due to ageing. Singapore National Eye Centre's (SNEC) recent Tanjong Pagar study found that over 80 per cent of people aged 60 and above have some form of cataracts.

Prolonged ultra-violet light exposure, long term use of medications such as steroids and certain illnesses like diabetes are also risk factors for the development of cataracts. In the young, cataract can be present at birth or develop as a result of injury.

What are the symptoms?

The first sign is usually blurring of vision. Other complaints may include frequent change of glasses due to increasing short-sightedness in the adults, colours appearing dull, poor vision in bright light, glare, haloes around lights, difficulty reading or watching television or driving at night.

How are cataracts diagnosed?

Your eye doctor will be able to diagnose your cataract from clinical examination when you come for an eye examination at the eye clinic.

What can I do to prevent cataracts?

There is no scientifically proven prevention. However, you can protect your eyes from ultra-violet light by wearing sunglasses regularly, eating a balanced diet, treating diseases such as diabetes, and refrain from smoking.

How can a cataract be treated?

How can my cataract be treated?

The notion of a cataract being "ripe" for surgery is a myth. Surgery will usually be advised by your surgeon when your poor vision caused by cataract cannot be corrected with glasses and interferes with your daily activities. SNEC surgeons are able to perform cataract surgery using techniques, machines and instruments, making cataract surgery comfortable, safe and quick to recover from.

Pre-operatively, your surgeon will counsel you regarding the surgical process, including discussing with you the expected outcome and possible risks and complications from the surgery. SNEC's team of nurses and counselors will also advise you of the dos and don'ts after the surgery.

Elective cataract surgery is performed as a day/ambulatory surgery, under local or topical anaesthesia, on one eye at a time. A short period of fasting is required before the operation. The vast majority of our cataract operations are by a technique called phacoemulsification. This uses ultrasound energy.

Phacoemulsification involves making a small incision of 1.8 to 3.0mm on the cornea. The vibrating phacoemulsification instrument is introduced into the eye through the small wound. It causes emulsification (softening) of the cataractous lens which is aspirated out through the instrument at the same time. The capsule of the lens is left behind which then receives the artificial lens implant. The surgery is completed without any need for stitches.

Post-operatively, you will need to instill eyedrops into the operated eye at regular intervals for up to 4 weeks. Light activities and good hygiene are advised. Potential contaminants to the healing wound such as from swimming and hair-washing should be avoided. Your experienced nurse will be able to advise you further of the details of your post-operative eye care. You should also return for check-ups at one day, within one week and at about a month from your operation.

This article was contributed by Singapore National Eye Centre (SNEC), which performs over 10,000 cataract surgeries a year. For more information, visit SNEC's website at