WHAT ARE CATARACTS?
Over half of those over 65 have some cataract development and in most cases this can be treated successfully with surgery. A cataract is not a skin that grows over the eye but a clouding of part of the eye called the lens. Vision becomes blurred or dim because light cannot pass through the clouded lens to the back of the eye.
What causes a cataract?
Cataracts can form at any age, but most often are a natural consequence of getting older. They develop slowly and are painless. In younger people they can result from an injury, taking certain medication, long-standing inflammation, or illness such as diabetes.
What are the symptoms?
Common symptoms may include the following complaints:
'I'm not seeing as well as I used to'
You may notice your vision is blurred, or that your glasses seem dirty or scratched.
'I sometimes see double'
The cloudiness in the lens may occur in more than one place, causing a double image.
'My vision is poor in bright light'
Bright light or very sunny days make it more difficult to see.
'I've noticed a change in colours'
As the cataract develops, its centre becomes more and more yellow, giving everything you see a yellowish tinge.
Experiencing these symptoms can also be a sign of other eye problems so it is important to consult you optometrist for an eye examination.
What can be done?
Early cataracts often make you more short-sighted, which, initially can be compensated for by altering the prescription of your glasses. Tinted lenses or shielding your eyes from the sun will help. However as the cataract continues to progress and the symptoms will increase over the following years. At this stage the most effective treatment for cataracts is a simple operation to remove the cloudy lens. We will advise you when you need to be referred to hospital. Cataract surgery is one of the most common surgical procedures and in most cases can be carried out under local anaesthetic on a day-case basis, without an overnight stay in hospital. Diets or drugs have not been shown to slow or stop the development of cataracts.
When should I consider having cataract surgery?
The simple answer is when you are noticing persistent problems with troublesome visual symptoms. It is an entirely individual decision depending upon the visual demands of your particular lifestyle; whether you are a keen reader, use computer screens a lot, need to drive and retain your licence etc. There are no universal or objective criteria. You alone are the best judge of whether or not you are having problems and how tolerable they are. The professional responsibility of the eye surgeon is to examine your eyes in detail in order to exclude any other eye disease that may or may not be a cause of your symptoms. It is also their duty to tell you the risks and benefits of cataract surgery so that you can make an informed choice as to whether or not you wish to proceed. It is important that you also have a clear idea of the realistic benefits of surgery as well as the risk. Can I have both cataracts done at the same time?It is generally agreed that the potential risks of bilateral cataract surgery (although small) outweigh the benefits, the most obvious of which is convenience. The greatest worry is the situation where there is an unpredictable complication; infection inside the eye, for example. Since both eyes might be affected the consequences could be disastrous.
What happens during a cataract operation?
In principle, your own lens is removed and replaced with a clear plastic lens implant. This is generally performed under local anaesthetic as a day-case procedure. The precise size and shape of both your eyes have to be measured beforehand in order to accurately calculate the optical power of the appropriate lens implant. This is done before your admission to hospital for the operation. On the day of your operation you will need to arrive at the hospital a few hours in advance so that you can be registered. The nursing staff will admit you to the day ward and put some dilating drops in your eye at least an hour prior to surgery. When you are brought down to theatre, you will be taken to the anaesthetic room where, if necessary, an intravenous line will be put into a vein in your arm. You will then be given some eye drops and probably an injection of local anaesthetic into the lower eyelid, although sometimes this injection is not needed.
You will then be taken into theatre and transferred onto an operating table with a special headrest that supports your head and neck. It is important that you are comfortable at this stage. You will be covered with a sterile drape except for the eye itself. A bright light from the operating microscope is shone onto your eye. Because of this you will be able to see anything further during the operation. This is quite common. You will not be aware of any sensation in the eye itself. Occasionally people report a sense of 'pressure'. The procedure takes about 10 minutes and is performed through a 2mm incision made to the eye, behind the upper eyelid. The cataract is liquefied using sound waves and drawn off with a needle. Laser is not currently used for cataract surgery. A foldable lens implant is put into the eye and unfolded inside. The incision is self-sealing and, in virtually all cases, no stitch is needed.
What should I expect after the operation?
Soon afterwards you will be taken back to the day-care ward.Please ask a relative or friend to collect you and accompany you homeYou will be given a bottle of eye drops to take home, containing a combination of antibiotics and steroid. You should expect to use these drops for about a month.When you are discharged from hospital, your eye will usually be covered by a soft pad with a plastic shield taped over it. Leave these in place overnight to protect the eye while the local anaesthetic wears off. The following morning you can remove the shield and pad, which you should throw away. After cleaning the eye, you should start using the eye drops. Your eye is likely to feel uncomfortable and 'gritty' for a few days and often looks a bit red. This is normal.The vision is usually bright but blurred at this stage but improves gradually over the first week.The important point to emphasise is that you can resume your normal daily activities straight away and there is no need for any restrictions.(Unless your vision is not good enough for driving)Your glasses will need to be changed by your optometrist. This can be done at a minimum of six weeks after surgery, by which time the eye has fully recovered.
What are the risks and complications of cataract surgery?
Cataract surgery has become one of today's most successful operations. If you have nothing else wrong with your eye other than the cataract, you have about a 99.9% chance of obtaining normal vision with your new glasses. Are there any long-term complications?A process that occurs almost always following cataract surgery, to a greater or lesser degree, is opacification of the posterior lens capsule - scarring of the membrane that supports the lens implant. This appears to be less common with modern types of lens implants but in 20-50% of cases it progresses to a degree that impairs vision. It occurs between six months and five years following cataract surgery and requires laser treatment if it produces visual symptoms. It is more common in children, young adults and those with diabetic visual retinopathy or inflammation inside the eye. SummaryModern small incision cataract surgery is a very successful operation with an excellent outcome in over nine out of ten cases.The risk of complications is low, and sight-threatening complications are rare.Most operations are carried out under local anaesthetic as a day-case procedure. You can return to your normal daily activities straightaway; there are no restrictions.The eye will feel gritty and uncomfortable for a few days but should not be painful.Visual recovery takes place for most people over the first week or two.You will be using eye drops for about a monthYou will need to replace your glasses with a new prescription once the drops are finished
What is a lens implant?
When the cloudy lens has been surgically removed it is replaced by a plastic lens implanted in the eye so that it can focus properly. Once the eye has healed a change of spectacles is usually required. Occasionally your doctor will decide the eye is not suitable for a lens implant. In these cases, contact lenses or special glasses will be prescribed instead.
Some patients are anxious about having cataract surgery and put off surgery, this is acceptable in the short term but if cataract surgery is put off for too long the developing cataract damages or destroys the lens capsule within the eye and reduces the chance of successful cataract surgery in the future.