What is a cataract?

A cataract is clouding of the natural lens of the eye. The lens of the eye in younger people is normally clear. A cataract forms when there is a build up of protein on the lens making it cloudy. This prevents light passing through the lens causing vision loss.

What is the lens?

The eye functions much like a camera. The lens is a clear part of the eye that functions to focus light onto the retina. The retina is the light sensitive tissue at the back of the eye.

In a normal eye the lens is transparent and the light passes through easily onto the retina. From the retina it is changed into nerve signals and sent to the brain to form an image.

If the lens is cloudy it no longer transmits light rays clearly to the retina, which is similar to the film in a camera. If the lens has become cloudy from a cataract the image you see will be blurred.

What causes cataract?

Types of cataracts include:

Age related – This cataract develops as a normal part of ageing.

Congenital – Babies are sometimes born with cataracts or can develop in childhood. It is common for the cataract to be in both eyes.

Traumatic – These cataracts are a result of an injury to the eye.

Secondary – These cataracts often develop from other health conditions such as glaucoma, prolonged use of corticosteroids and diabetes, excessive ultraviolet light may also be a cause.

What are the symptoms of cataract?

Cataracts characteristically form very slowly and cause few symptoms until they start to block light.

Symptoms Include:

  • Vision that is blurry, hazy or foggy;
  • Increased sensitivity to light and increased glare;
  • Difficulty with night vision including glare from oncoming headlights;
  • Colours often become duller and darker;
  • Near vision in glasses may improve for a short time; and
  • More rapid changes glasses prescriptions than would normally be expected.

How is cataract diagnosed?

A comprehensive eye examination with the ophthalmologist, including dilating the pupil will allow diagnosis of cataract.


The Ophthalmologist will need to measure the length and curvature of your eye to determine the prescription of the intraocular lens (IOL) that will replace the cloudy lens.

Your Ophthalmologist will discuss any lifestyle factors such as sporting and leisure activities that will help determine the type of lens that will best suit your lifestyle requirements.

Intraocular lens (IOL)

The artificial lens implant is called an intraocular lens (IOL). It is a transparent disc made of acrylic, a safe, stable plastic that has been used for many decades with a shape similar to the natural lens.

Many different types of IOLs are available to suit different patient needs, both surgically and for lifestyle reasons. The IOL choice is tailored to your individual needs. Lenses can correct astigmatism. Multifocal lenses, which allow vision for distance and near are available.

Surgical techniques

Cataract surgery is the most commonly performed eye operation and one of the most commonly performed of all surgeries. It has a high success rate due to the high level of expertise amongst Australian surgeons and the cutting edge methods used. The most common technique is phacoemulsification.


The surgeon makes a very small incision (about 3mm) near the border of the cornea and sclera or in the cornea. The natural lens is then suctioned away with a tiny probe. The IOL is then inserted into the eye. The incision is so small that it often requires no stitches. The operation takes only 30 – 45 minutes. It is a day procedure and is associated with only minimal discomfort.

Local anaesthetic and sedation are given to reduce anxiety. After surgery the eye is covered with a shield for protection. Patients return the following morning for the surgeon to review the results and to go through post surgery instructions.


Laser-assisted cataract removal

At Envision Eye Centre we offer the newest surgical technique in cataract surgery, laser-assisted cataract removal. This is when the incision and the breaking up of the lens are done with the assistance of a laser, known as a femtosecond laser.

Laser cataract surgery is a new bladeless surgery technique, first used in 2011 in Australia. The new technology uses a computer guided Femtosecond laser to perform the early stages of the cataract operation, cutting the tissue with a degree of precision that manual techniques struggle to match.

Femtosecond laser technology has already been well proven in Laser vision correction surgery such as LASIK for more than ten years with well over 1 million procedures performed to date.

The advantages of laser assisted cataract surgery include:

  • Bladeless procedure;
  • More precise incisions;
  • Gentler, lower energy procedure;

Refractive lens exchange

This operation closely resembles cataract surgery. It may be suitable for some patients even though they have only a minor or no cataract. The objective is to relieve these patients of the dependence on glasses and contact lenses when other treatments, such as laser vision correction, are not possible.

What are the risks of cataract surgery?

As with any surgery there a risk of complications. Approximately 99% of cataract cases are successful. There is an overall incidence of complications of about 1% of which 1 in 500 may be severe.

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