Cataract surgery is the most common procedure performed in the UK and one of the safest. But it’s far from simple. Here is our need-to-know guide on the potentially life-changing operation.
People with cataracts who opt for surgery are sometimes surprised by the complexity of the procedure. But those who go through with it are often overwhelmed with the results. Consultant ophthalmologist, Anthony O’Driscoll from Nuffield Health’s Warwickshire hospital, lifts the shroud on the practice of restoring sight.
Cataracts cloud the lens inside your eye – not the surface
"Many people come for a consultation expecting that the procedure requires only a cleaning of the eye’s surface, when in fact it’s the lens that grows cloudy. The lens sits behind the pupil inside your eye. Light enters the eye through the pupil and is focused by the lens onto the retina. When cataracts form, the lens is unable to properly focus and create a clear picture."
Cataracts are treated by removing the lens and replacing it with a synthetic one
"Cataract removal is a micro-surgical procedure and is commonly done using a technique called phacoemulsification. First, we make a small incision in the eye and dilate the pupil to access the lens. Then, an ultrasonic probe is inserted to break up and emulsify the cataract. The soft tissue is then drawn out by suction through the probe. Finally, we insert a synthetic lens with a strength customised for the patient using a formula based on a biometrical measurement of their eye."
Most procedures are done under local anaesthetic
"The vast majority of patients opt to go under a local anaesthetic, which means they’re awake throughout the procedure. We work hard to make sure patients understand the experience they’re likely to have. There are different levels of local anaesthetic available, from strong eye drops to an injection around the side of the eye. Some people additionally opt to be sedated, while a rare few choose general anaesthetic which takes a bit longer to recover from.”
“If you’re under local anaesthetic, you won’t feel any pain, but might experience a bit of pressure and the sensation of fluid running over the eye. Some patients who just take the eye drops report seeing a dazzling multicolour light show during the procedure, in others the eye will simply blank out until the anaesthetic wears off.”
The results are often surprisingly good - but aren’t guaranteed
“The eye is extremely complex and is made up of loads of different parts. If other parts of the eye aren’t functioning properly, then the results might be underwhelming. But most patients are pleasantly surprised by the vision that returns to them after just a few days. Cataracts often develop slowly over time and people forget how good their vision once was. Some patients even find that they would like their other eye operated on to bring it up to the same standard.”
Let’s be clear about the risks
“Thousands of cataract surgeries are carried out without incident in the UK every year. But this is complex micro-surgery and it doesn’t always go to plan. The pocket that the lens sits in can be torn, all or part of the cataract can fall back into the eye as it is being removed, or infection can develop. Even if the surgery goes smoothly there is a small chance of posterior capsule opacification (PCO) – a condition where a membrane grows over the back of the new lens months or even years after the surgery is completed.”
“In most cases, complications like these can be treated with medication or further surgery. However, very rarely, in one out of every 1000 cases, surgery is directly responsible for permanent sight loss in the treated eye.”
Before choosing surgery, you need to weigh those risks against the potential gains
“Not everyone with cataracts needs cataract surgery. If you can go about your daily life without sight loss affecting your independence then you probably don’t need to think about surgery just yet. That said, cataracts generally get worse over time, and so it may be something you want to consider in the future. If you’re unsure, get an eye test or ask your GP to refer you to a specialist.”
Cataracts are common, but you can reduce your risks of developing the condition early
“As you get older, your risk of developing cataracts rises as the lens in the eye naturally degenerates over time. But there are some factors which can speed this process up, meaning some people may develop cataracts much earlier in life. High UV exposure can damage your eyes, so wear sunglasses on bright days. Smoking and diabetes have also been linked to early onset cataracts.”
“There are also occupational risks. Glass blowers, foundry workers and others who are exposed to high heat and strong light, including infrared light, stand a greater chance of developing cataracts early.”