Cataract

Cataract is a clouding of your eye’s natural lens, which normally adjusts your focus to see things close up and at a distance. As you age, the proteins that keep the lens clear can clump and start to cloud the lens. Over time, this can prevent light from entering the eye and can cause reversible blindness.

The WHO estimates cataract to be responsible for 48% of blindness globally.

Cataracts are the leading cause of blindness among those 55 years and older.

Risk Factors

Age, long-term sun exposure without protection, and smoking are the main risk factors for developing cataracts. There is also a higher risk of developing cataract after injury to the eyes, eye surgery, and radiation therapy to the upper body. People with diabetes are at higher risk of developing cataracts earlier, especially if blood glucose levels are not well controlled.

Signs & Symptoms

Cloudy or blurry vision, dullness or fading of colours, sensitivity to glare or car headlights, and haloes around lights are common symptoms of cataracts. You may notice you are changing glasses prescriptions often but your vision does not improve.

Prevention, Treatment and Prognosis

Prevention

Sun protection, including wraparound sunglasses and a wide-brimmed hat, prevent ultraviolet light causing damage to the eyes. Smoking cessation is also important for preventing cataract, as well as other eye conditions like macular degeneration. People with diabetes are strongly advised to have annual eye checks to look for any cataract, as well as diabetic retinopathy, so these may be treated promptly.

Treatment

Once cataract has developed, it will often continue to progress and affect your vision. If a cataract has sufficiently developed, surgery to extract the cloudy lens and implant a new, artificial intraocular lens is the definitive treatment. It is a quick day surgery that does not involve general anaesthetic in most cases.

Prognosis

Cataracts are not reversible, and if untreated, can lead to blindness. Fortunately, surgery provides a curative treatment for cataract and can restore vision, usually without the requirement for glasses.