You’ve just celebrated your 60th birthday and have turned up to your regular yearly eye test feeling pretty good – you’re generally fit and healthy and have no noticeable vision problems. But then your optometrist gives you a birthday present you could have done without – telling you that you have an early cataract.
This triggers a bunch of questions, such as exactly what is a cataract and will you need to have cataract surgery immediately? The good news is that you’re not likely to need to be rushed into cataract surgery but it will still be helpful to understand what vision problems to look out for that might indicate those cataracts are ready to be removed.
What is a Cataract?
A cataract refers to any opacity of the lens inside the eye. This lens is also called the crystalline lens, a transparent anatomical structure that sits behind the coloured iris near the front of your eyeball. In addition to being responsible for flexing its shape to allow focus at different viewing distances, the lens must remain optically clear to allow light to pass through it.
At birth, this lens is crystal clear (barring a congenital cataract). As we age, various factors such as UV exposure and oxidative stress change the structure of the fibres in the lens, resulting in the crystalline lens becoming increasingly hazy with time. There are three types of age-related cataract:
- Nuclear sclerosis: the nucleus of the lens is its central core. Nuclear sclerosis refers to the development of a yellowish-brownish haze in this area.
- Cortical cataract: the cortex of the lens refers to the lens fibres surrounding the nucleus. When viewed from the front on, a cortical cataract appears as white or grey spoke-like opacities radiating from the outer edge of the lens.
- Posterior subcapsular cataract: surrounding the cortex of the lens is the capsule. A posterior subcapsular cataract is a dense plaque-like opacity that grows just beneath the capsule at the back surface of the lens.
The vision problems caused by a cataract will vary, depending on the degree of the cataract and its location, or type. In the early stages, a cataract will cause no noticeable issues at all. Eventually, someone with a progressing cataract will begin to notice their vision is blurry or hazy, and not as crisp as it once was.
A person with nuclear sclerosis may also notice changes to their colour vision as the brownish clouding of their lens nucleus filters out certain wavelengths of colour from reaching the retina. The cataract may also affect contrast sensitivity, noticed during activities such as trying to read in poor light like a menu at a dimly lit restaurant or driving in rainy conditions.
Cortical and posterior subcapsular cataracts can contribute to an increase in glare sensitivity, which translates to increasing difficulty with driving at night when faced with oncoming car headlights or street lights. Even indoor lights may become uncomfortable to view. The extent to which these vision problems impact an individual’s daily function is typically what drives someone to undergo cataract surgery.
What is a Cataract Caused By?
Apart from age, which is by far the most common cause of a cataract, the formation of a cataract is also related to other risk factors, such as:
- The prolonged use of medications such as corticosteroids, whether oral or in eye drop form
- Systemic metabolic diseases such as diabetes
- Trauma, such as physical trauma or an electric shock
- Excessive exposure to sunlight and UV radiation
- Having a previous inflammatory eye disease
- Certain types of eye surgeries, including retinal detachment repair
Cataract surgery is one of the most commonly performed surgical procedures in the developed world. As cataracts are a normal part of ageing, all those who reach a reasonable life span are expected to develop some degree of cataract, though unfortunately, not everyone has access to basic eye care, such as cataract surgery.
Fortunately for us in Australia, cataract surgery is readily available through any number of highly skilled and experienced ophthalmologists.
Typically, a cataract surgery procedure is quick and uneventful. It is performed as day surgery and most eye specialists take only 20 minutes per eye for uncomplicated cases. After having the eye numbed with a local anaesthetic, a small incision is made in the cornea. This allows a surgical tool to be inserted into the eye to break up the cataract into smaller pieces, which can then be suctioned out. Different ophthalmologists will have their own preferences as to which technique they use to fragment the cataract. In Australia, some surgeons will use a femtosecond laser to perform the majority of this, while others prefer to utilise a technique known as phacoemulsification. Both methods are safe and effective, with similar visual outcomes in uncomplicated eyes.
After the cataract surgery, an implant known as an intraocular lens is inserted in the place of the removed cataract. This implant is important as it bends incoming light to fall onto the sensory retina to allow for clear vision. One great benefit of cataract surgery is that many people are able to have an intraocular lens that accounts for their eye’s prescription, meaning they no longer need to wear glasses for long-distance vision after their procedure.
Call us on (03) 9070 5753 for a consultation.
Note: Any surgical or invasive procedure carries risks. Before proceeding, you should seek a second opinion from an appropriately qualified health practitioner.