A cataract is clouding or opacity of the lens inside the eye. It causes gradual blurring of vision and often glare. In a normal eye this lens is clear. It helps focus light rays onto the back of the eye (the retina), which sends messages to the brain allowing us to see. When a cataract develops, the lens becomes cloudy and prevents the light rays from passing onto the retina. The picture the retina receives becomes dull and fuzzy. A cataract usually forms slowly and most people experience a gradual blurring of vision.
Cataracts usually form slowly over years causing a gradual blurring of vision, which eventually is not correctable with glasses. In some people the vision can deteriorate relatively quickly. Developing a cataract can also cause glare, difficulty with night-time driving and multiple images in one eye which can affect the quality of the vision.
Most forms of cataract develop in adult life. The normal process of ageing causes the lens to harden and become cloudy. This is called an age-related cataract and it is the most common type. It can occur at any time after the age of 40. Although most cataracts are age-related, there are other types, including congenital (present at birth), drug induced (steroids), and traumatic (injury to the eye). Cataracts are also more common in people who have certain diseases such as diabetes.
Hello, my name is Rathie Rajendram. I'm a consultant for Moorfields Eye Hospital who performs cataract surgery. You are watching this video as you've been referred for cataract surgery or are interested in finding out about cataracts.
In your eye there is a natural lens, as you get older it becomes cloudier and stiffer. Sometimes people can develop changes like this at a younger age, but it's usually for another cause.
Such as they were born with it in congenital cataract, or for a metabolic or a drug-related cause such as diabetes changing in the lens, or steroid induced, or they may have had an injury to the eye or surgery on the eye. The most common cause of cataracts, however, is the aging process.
Once the lens starts to get cloudier and stiffer you may become more and more short-sighted, and your vision blurred. This is when people will start to call it a cataract.
The initial management of cataracts is to obtain or update your glasses from the optician. You may find that as you get older you need to do this more frequently. At the point that the optician cannot improve your vision any further with glasses, or contact lenses, they will refer you to the eye hospital to the Cataract Clinic, to be considered for cataract surgery.
The operation itself involves a local anaesthetic where we just numb the eye, and you shouldn't feel any pain. Occasionally people will request to have sedation, which is an injection through the hand, or rarely they will have general anaesthetic, where they need to be put to sleep for the procedure. But this is usually because they have not been able to stay still for a duration of the time.
The operation what takes on average 20 minutes. During this time, once the eye is numb, we make very small incisions into the eye. We make a hole in the bag that holds the Cataract, which is called the capsule. Once we got to the cataract we break it up with ultrasound and then we remove it.
The lens
We then insert an artificial intra-ocular lens, which stays in the bag for life. The lens that we provide on the NHS is of one focal power. So, we correct you for either one distance or the other. This means that if you aim to have your distance vision improved you will need reading glasses after the operation. If you choose to remain short-sighted so that you can see close without glasses you will need glasses or contact lenses to see in the distance.
Astigmatism
If you have an astigmatism your eyeball will be more rugby ball shaped than football shaped naturally, this means a standard mono-focal intra-ocular lens may not fully correct the vision. And you may need glasses for distance and near after the operation. Toric intra-ocular lenses are special lenses which aim to reduce your astigmatism when inserted. They are suitable for patients with a regular astigmatism, and you may be eligible for them on the NHS at our Moorfields sites, if your astigmatism is 1.75 diopters or more.
Monovision
Some people wish to be less spectacle dependent and may choose to have monovision, if both eyes need operating on, or if they have good vision in one eye. This means that one lens will be for correcting your eye for distance and the other eye will have a lens for near vision. This would mean that you should hopefully have good distance vision with one eye, and with the other, be able to see the menu or read messages on your phone. You will, however, still need to wear glasses for longer periods of reading and for night driving. The NHS's primary focus is to aim to remove the cataract and not to guarantee spectacle independence.
Privately there are available other types of lenses, including multi-focal intra-ocular lenses which aim to improve distance and near vision. If you chose to go privately you would need to arrange the review privately by yourself, and some of the tests may be repeated. If you continue to go privately you should cancel your NHS appointment. Unfortunately there is no facility to top up on the NHS to have the private internal lens fitted during an NHS operation.
Visit Moorfields Private for more information about the alternative lenses available: https://www.moorfields.nhs.uk/private/eye-conditions-and-treatments/cataract
Risks and benefits
Cataract surgery is one of the most commonly performed surgeries with 330,000 operations being performed each year. Serious complications are uncommon and visual outcomes in over 90 per cent of cases are excellent. Any operational unfortunately has a risk, and although cataract surgery is straightforward, one in a thousand people can get a problem which causes their vision to be significantly or permanently reduced. One in a hundred may need further surgery if a complication happens at the time of surgery requiring it. One in 20 people may have a complication that can be rectified at the time of surgery. For one in ten people the bag that holds a lens may get hazy. The cataract will never regrow, but the bag may be hazy and give the feeling blurred vision. If you do get blurred vision from this, the treatment is a simple laser procedure which we can arrange for you.
Cataracts is a normal aging process in life, and so it doesn't need to be operated on unless the vision is affecting you significantly. If you drive you may also need to make sure that you’re at a level to have ‘driving standard’. You could speak to your optician for them to check whether you would need to have surgery to maintain your driving standard. If you want to continue to drive, we can also have that discussion in the cataract clinic if you feel your vision is troubling you.
Thank you for watching the video and I hope that you know more about cataracts now, and the cataract surgery, and the risks and benefits.
You can self fund or use private medical insurance to fund your treatment.