Internal radiotherapy is also called brachytherapy. It can treat some types of eye cancer by using a small radioactive disc called a plaque.
What is plaque radiotherapy?
Plaque radiotherapy delivers high dose radiation to a small area. You have a small radioactive metal disc placed over the cancer on the affected eye. The disc comes in different sizes but are small enough to place over the cancer on the eye. The plaque continually gives off radiation while it is in place and it treats a small area.
It treats the part of the eye it covers. Side effects can vary slightly depending on the type of radioactive material used. It doesn’t affect any other part of your body.
To attach the plaque to your eye you have an operation, usually with a general anaesthetic. You will stay in hospital for a few days while the plaque stays in place. This is because there is a small risk of radiation exposure to others.
The plaque is removed before you go home, so there will not be any radioactivity in your eye when you leave the hospital.
Your eye specialist will explain your treatment, how long you stay in hospital and how it will feel.
When you might have it
You can have plaque radiotherapy for different types of eye cancer. For example, a melanoma inside the eye that has not spread into the socket. You can’t have this treatment if your cancer is too thick. This is because the radiation would not reach all the cancer. In this case, you would have external beam radiotherapy instead.
Before you start the treatment you have an appointment to plan your radiotherapy. Your radiation oncologist works with other radiation specialists to calculate the dose of treatment. The amount you have and the time it is in place depends on:
- the thickness of the cancer
- the size of the cancer
- the size of plaque used
Your treatment usually starts within 2 weeks. In this time the specialist works out the correct dose for you. Your radiotherapy team will let you know when your treatment will start.
To have plaque radiotherapy you need an operation. You usually have a general anaesthetic so you are unconscious. In some eye centres, you might have a local anaesthetic. So you are awake but the eye area is numbed.
You have the plaque sewn in place over the eye cancer. The inner lining placed directly on the eye cancer contains the radioactive treatment. The outer lining has a protective shield. It can stay in place for up to a week, depending on how thick your cancer is. The thicker the cancer is the longer the treatment lasts.
The surgery takes about an hour. Afterwards you may have some discomfort or pain, you will have painkillers to relieve this. Although you might have some pain after surgery, you do not feel the radiation from the plaque.
Usually you have a gauze pad and a protective shield over the eye being treated. These stay over your eye while the plaque is in place. Your nurse will check your eye regularly for signs of inflammation or infection. You might have eye drops to help reduce the risk of an infection.
Will I be radioactive?
While you have the plaque in place, you stay in a single room in the hospital. This is because the plaques gives off a small amount of radiation meaning other people in the room are exposed to it. Your nurses will check the amount of time your visitors spend in your room. Although the radiation level is very low, pregnant women and children should not visit at all.
Staying in hospital
The plaque can be in place from 2 to 7 days. During this time there are precautions you need to take including:
- always let your nurse know before you leave and when you return to your room
- do not flush the toilet or empty the bath, your nurse will do this
- do not have a shower
This is so your nurse can check the plaque is in place and has not fallen out. It is very unlikely for the plaque to fall out, but checking it regularly is an important part of your care.
It can be quite difficult and boring having to stay in one room, even if it is only for a few days. Make sure you take something to keep you occupied. Recordings of favourite music or talking books are a good idea. It is safe to watch TV as it needs very little eye movement. The ward usually provides a radio or TV. If they can’t provide one, ask if you can take your own in.
When the treatment time has finished, you have another operation to remove the radioactive plaques. After this, all the radiation is gone. You do not give off any radiation to yourself or anyone you are with. All your personal belongings that were in the room with you during the treatment are safe to take home. They won’t be radioactive.
You usually go home the same day or the day after the plaque is removed. You may have eye drops to use at home. These help to reduce the risk of infection and inflammation.
You shouldn’t feel unwell, but it is common for your eye to look red for a few weeks. You may also have blurred vision in the treated eye. How long this lasts does vary, but it can be a few weeks. Do speak your eye specialist if you have any concerns.