Published: 6 July 2020 | Last updated: 15 September 2026 | Publisher: Smart Vision Optometry
At a glance
- A cataract is clouding of the normally clear lens inside the eye.
- Symptoms can include blurred or hazy vision, glare, halos, faded colours and difficulty seeing at night.
- Early cataracts may be monitored or managed with an updated prescription; surgery is considered when vision changes affect everyday life.
What is a cataract?
A cataract is a cloudy area in the lens of the eye. The lens normally helps focus light onto the retina. As it becomes cloudy, vision may become blurred, hazy or less colourful. Cataracts can occur in one or both eyes and usually develop gradually.
Healthdirect Australia’s cataract guidance explains that cataracts are common with ageing, although younger people and children can also be affected.
What symptoms can cataracts cause?
- Cloudy, blurred or hazy vision.
- Glare or increased sensitivity to bright light.
- Halos around lights or difficulty driving at night.
- Colours that appear faded or yellowed.
- Frequent prescription changes or double vision in one eye.
Cataracts do not usually cause eye pain. Sudden vision loss, new severe eye pain, flashes, a sudden increase in floaters or a curtain-like shadow should be assessed urgently because they are not typical gradual cataract symptoms.
Who is at greater risk?
Age is the main risk factor. Diabetes, smoking, heavy alcohol use, a family history, eye injury, previous eye surgery, radiation exposure and long-term use of some steroid medicines can also increase risk. Ultraviolet exposure is another modifiable factor, so suitable sunglasses and a broad-brimmed hat are sensible outdoor protection.
How are cataracts diagnosed?
An optometrist or ophthalmologist can examine the lens and assess how vision is affected. Testing may include visual acuity, prescription measurement, slit-lamp examination and other eye-health checks. Cataract symptoms can overlap with other eye conditions, so diagnosis should not be based on symptoms alone.
When is cataract surgery considered?
Early cataracts may be monitored, and a new prescription, brighter task lighting or glare control may help for a time. Surgery is considered when the cataract interferes with activities such as reading, driving, work or independent living.
During cataract surgery, an ophthalmologist removes the clouded lens and replaces it with a clear artificial intraocular lens. Timing, lens choice, expected benefit and risks depend on the individual eye and health history; no result or recovery time should be guaranteed.
The National Eye Institute’s cataract overview provides additional information about diagnosis, monitoring and surgery.
Arrange an eye assessment
Read about the relationship between myopia and cataracts, review SVO’s advanced eye health testing, or arrange an appointment if you have gradual vision changes or cataract concerns.
Cataract questions
What is a cataract?
A cataract is clouding of the normally clear lens inside the eye. It can make vision blurred, hazy or less colourful and may affect one or both eyes.
What are common cataract symptoms?
Common symptoms include gradual blur, glare, halos around lights, faded colours, difficulty seeing at night and frequent prescription changes. Cataracts do not usually cause pain.
When is cataract surgery recommended?
Surgery may be recommended when a cataract affects everyday activities or safety. An ophthalmologist discusses the likely benefits, risks, timing and lens options for the individual.
