Cataracts and cataract surgery
What is a cataract?
Just behind the pupil of your eye is a lens made from natural proteins and other substances. Normally this lens is totally clear so that the light can pass straight through the lens and can be focused on the retina. The retina is at the back of your eye and is like a film in a camera. It is where the light is turned into nerve impulses that are transmitted to your brain so that you can see images. A cataract is when the lens becomes cloudy and the light cannot pass through it easily causing your vision to be blurred.
What are the symptoms of cataract?
The main symptom is blurred vision. Cataract can also cause glare that interferes with driving, particularly at night. Sometimes early cataract can cause your glasses prescription to change relatively quickly, making you more short-sighted. Occasionally cataract can form in one eye and the patient doesn’t notice it because they can see well with the other eye.
What causes cataract?
The vast majority of cataracts are age-related and most cataracts occur in patients over the age of 60. Usually these age-related cataracts happen for no particular reason and the eye is otherwise completely healthy. The formation of cataract can be speeded up by some medical conditions such as diabetes.
Sometimes the use of certain medications can be associated with cataract formation such as steroids, immunosuppressive medicines or chemotherapy or even radiotherapy. Eye conditions such as recurring uveitis (inflammation within the eye) or prior eye operations can themselves cause cataract. Eye trauma can sometimes result in cataract.
What is the treatment for cataract?
Cataract is treated by surgery. Your eye surgeon makes tiny incisions in the eye and removes the natural lens that has become cloudy from the cataract. An artificial plastic lens is inserted into the eye allowing you to see clearly again.
It is important to realise that even if you have a cataract you don’t have to have surgery. You should only have surgery if you feel that your sight is being affected badly enough for you to really want surgery.
It is very rare for cataract surgery to be urgent (from a medical perspective) and the timing of the procedure is usually up to the patient. It is indicated when you feel that the potential benefits outweigh the potential risks and that is a very personal decision. There is a legal standard of vision for driving purposes and this is often the reason that cataract surgery is necessary in people who drive.
What are the risks of cataract surgery?
Although cataract surgery is very commonly undertaken and is generally speaking a safe operation there are risks involved.
Some of the most serious risks are:
- infection in the eye,
- bleeding in the eye,
- retinal detachment,
- persistent inflammation
- or swelling at the front or back of the eye that reduces vision and damage to other parts of the eye.
If you were to suffer a very serious complication you could possibly lose the vision in the eye. All of these complications are rare and you should discuss all the possible risks with your surgeon and ask about anything you don’t understand. It is important that you understand the risks so that you can make the decision about when or whether to have cataract surgery
What should you expect from cataract surgery?
Cataract surgery has developed hugely over the past twenty years. Nowadays, the vast majority of cataract surgery is undertaken under local anaesthetic with the patient awake; it is not painful.
A few weeks before the operation your eye will be carefully measured on a special machine and these measurements are used by your surgeon to decide what strength of lens is required for your particular eye.
On the day of surgery you go to the hospital and are prepared for surgery by the nurses and the doctor. Often the doctor will run through the options with you again and make sure that you understand everything about the potential benefits and risks so that you can give the final consent to proceed.
Just before your operation you will be given the local anaesthetic that will consist of either drops or an injection around the eye. After you receive the local anaesthetic your eye will be completely numb and you needn’t worry about feeling pain.
When you are in the operating theatre the surgeon and the team will make a final check to make sure you are the right person getting the correct operation. The surgeon cleans around your eye, usually with a special type of iodine. Then a paper sheet is placed over your face; sometimes patients are worried about this but there is always lots of air pumped in under this sheet so there is nothing to be concerned about.
After these preparations the surgeon does the work. You will hear what’s going on and you will feel lots of water washing around your eye. You’ll hear the beeping of the monitoring machines and the surgeon talking to the nurses. The machine that the surgeon uses to remove the cataract is very high-tech. It makes lots of whining and buzzing noises and some of the machines even announce the settings with a robotic voice!
The operation takes about half an hour. Often patients are worried that they will see everything that is happening but this is not the case. All you will see once the surgeon’s microscope is in place are bright lights. After the operation your eye will either have a shield or a patch to protect it.
What is the recovery like?
Everybody recovers at a different rate. You should take it easy for a few weeks after cataract surgery. Most people notice an improvement after a few days but it can take longer depending on how hard the cataract was in the first place. You should not have any major pain after cataract surgery but you will probably notice a gritty-sensation that can be somewhat uncomfortable. This is very common and is because the epithelium (transparent skin) on your eye is recovering over the incisions that were made. This can persist for a number of weeks.
You will be prescribed lots of drops to be used for a number of weeks after the surgery. These drops will usually be a mixture of antibiotics, anti-inflammatories and lubricants. It is very important to use the drops as prescribed. The surgeon will usually arrange for you be routinely checked in the recovery phase.
If your vision was getting better and then suddenly gets worse, if you develop unexpected pain or if you notice any other symptoms that cause concern you should immediately come for examination by an eye doctor so that problems can be identified and dealt with early.
You will need new lenses for your glasses after cataract surgery so you should get these changed after a few weeks or after you have your routine follow-up with the eye doctor. Sometimes, months or even years after the cataract surgery a cloudy film can grow across the back of the artificial lens. This can be usually be easily fixed with a relatively minor laser procedure.
A cataract is when your own lens becomes cloudy. This is treated with cataract surgery and an artificial lens is used to replace the cloudy natural one. Cataract surgery is an excellent treatment and a very common and generally safe operation but there are risks. You should only undergo surgery when you feel that the potential benefit outweighs the risks. Your eye surgeon will be able to help you understand the issues.