What an ophthalmologist wants you to know about cataracts
Posted on 19 October 2020
A cataract is an eye condition that is easily remedied with a routine surgical procedure.
Lorraine Petersen from Mitchell’s Plain explains that her mother’s failing eyesight was affecting her quality of life. ‘Her cataracts made it difficult for her to see and she lost confidence. At one point, she stopped going out altogether.’ Fortunately, Lorraine’s mother was selected for a cataract removal procedure at Mediclinic Milnerton as part of a large-scale corporate social investment project. After a successful operation, she’s regained clear vision. ‘I’m very glad she was selected for the surgery,’ Lorraine says. ‘She’s able to enjoy her grandchildren’s school concerts again – and to read the subtitles on TV.’
What is a cataract?
A cataract is a progressive clouding of the natural lens of the eye, which is located behind the pupil. This clouding can disrupt the vision. ‘There are many different types and causes of cataracts, but the most common is normal age-related degeneration of the eye’s lens,’ says Dr Alan Sara, a supporting ophthalmologist at Mediclinic Howick. ‘If we live long enough, we’re all destined to get them.’
Dr Zoran Aleksic, a Mediclinic Cape Town ophthalmic surgeon, adds that while you’re unlikely to notice changes to your vision initially, a cataract may grow denser and cloud more of the lens over time. This can make your vision foggy as less light reaches the retina. It’s rather like looking through a misted-up window.
How do they develop?
Most cataracts develop slowly and are left undiagnosed for a long time. Dr Willem Gerber, an ophthalmologist at Mediclinic Durbanville, explains that as the cataract grows denser it will lead to more noticeable symptoms, such as:
- Clouded, blurred or dim vision
- Increasing difficulty with vision at night
- Sensitivity to light and glare
- Need for brighter light for reading and other activities
- Seeing ‘halos’ around lights
- Frequent changes in eyeglass (spectacle) or contact lens prescription
- Fading or yellowing of colours
- Double vision in a single eye.
What is the cure?
The short answer is surgery, with the intricacy of the procedure being dependent on how dense the cataract is. ‘With early cataracts, we do a procedure called phacoemulsification, which, in simple terms, is a micro-incision surgery technique where we break up the cataract with a probe that produces ultrasound waves and sucks out the fragments,’ says Dr Gerber.
‘For cataracts that have progressed to the point where patients can only see large hand movements, we can’t use ultra-sound to break it up as the cataract is too hard. So we make a bigger incision to remove the cataract as a whole.’ The eye’s clouded lens is then replaced with a synthetic version called an intraocular lens (IOL) to restore clear vision.
The monofocal IOL has a fixed focus for one distance. Presbyopia-correcting IOLs (also known as multifocal IOLs) have the potential to help you see clearly at more than one distance. Toric IOLs are designed to correct both cataracts and astigmatism (an imperfection in the curvature of your eye) at the time of surgery.
Can you prevent them?
In short, no. Although no one knows exactly what causes cataracts, the most common type is related to ageing. ‘Scientists think there may be several additional causes for cataracts, including smoking, diabetes and eye injury – either soon after injury or years later,’ says Dr Aleksic. And although you may develop cataracts in both eyes, a cataract cannot spread from one eye to the other.