Cataracts
Clouding of the eye's natural lens — the world's leading cause of reversible blindness.
Overview
A cataract is a progressive opacification of the crystalline lens, causing blurred vision, glare and reduced contrast. It is the leading cause of treatable blindness worldwide. Modern phacoemulsification surgery is one of medicine's safest and most effective operations.
Symptoms
- • Gradual painless blurring of vision
- • Increased glare from lights, especially at night
- • Faded colours
- • Frequent changes in glasses prescription
- • Double vision in one eye
Risk factors
- • Age >60
- • Diabetes
- • Smoking
- • Excessive sun exposure
- • Steroid use
- • Family history
Causes
- • Age-related lens protein denaturation
- • Diabetes mellitus
- • Trauma, intraocular surgery, uveitis
- • Long-term corticosteroid use
- • UV light exposure, smoking, heavy alcohol
- • Congenital (rare): infection, metabolic disorders, genetic
🚨 Red flags — seek urgent care
- • Sudden visual loss — alternative diagnosis (e.g. retinal detachment, vascular event), urgent
- • Painful red eye with vision change
- • Floaters with flashing lights
When to seek care
- • Vision affecting daily activities or driving
- • Sudden visual change — urgent
- • Any new eye symptom in diabetes
Diagnosis
- • Slit-lamp examination
- • Visual acuity testing
- • Assessment of impact on daily function
- • Biometry for surgical planning
Treatment
- • Updated spectacles and brighter lighting in early disease
- • Cataract surgery (phacoemulsification with intraocular lens) — definitive treatment
- • Surgery is offered when vision affects quality of life, not based on a strict acuity threshold
- • Treat coexisting eye disease (glaucoma, AMD, diabetic retinopathy)
Prevention
- • Stop smoking
- • Wear UV-protective sunglasses
- • Manage diabetes
- • Use steroids at the lowest effective dose
Complications
- • Visual impairment and falls
- • Reduced quality of life
- • Surgical complications: posterior capsule rupture, endophthalmitis (rare), posterior capsule opacification (treatable with YAG laser)
Prognosis
Cataract surgery restores vision in more than 95% of cases with low complication rates and rapid recovery.
Education & self-care
Cataracts are very common and highly treatable. Modern surgery restores vision quickly and safely for the great majority of people.
Frequently asked questions
When is the right time to have surgery?
When vision affects your everyday activities — there is no benefit in waiting for cataracts to 'ripen'.
Will I need glasses after surgery?
Many people achieve good unaided distance vision; reading glasses are usually still needed unless multifocal lenses are chosen.
Can drops or diet reverse a cataract?
No proven medical treatment dissolves a cataract. Surgery — typically a 20-minute day-case procedure — is the only effective treatment and is highly successful.
How do I know it is time for surgery?
Surgery is offered when the cataract interferes with the activities you need or enjoy — driving, reading, work, hobbies — rather than at a fixed visual acuity threshold.
What are the main surgical risks?
Serious complications are uncommon (under 2%). The main ones are posterior capsule rupture, infection (endophthalmitis, around 1 in 1,000) and a delayed clouding of the back capsule that is treated with a quick laser.