Some people may develop eye problems as a late effect of treatments for cancer during childhood. Treatments that can lead to eye problems include radiation therapy, radioactive iodine (for thyroid cancer), certain chemotherapy or other drugs and stem cell transplant.
The eyes work with the brain to let you see. Each eye works much like a camera. It collects light, turns it into electric signals and sends those signals to the brain. The brain then turns the signals into a visual image or picture for us to see. We have 2 eyes, so 2 pictures are usually created. If we lose the vision in one eye, we can still see most of what we could see before.
People who are treated for cancer as children may have one or more of the following eye problems as a late effect of treatment:
- cataracts, which is clouding of the lens of the eye
- glaucoma, which is increased pressure within the eye
- underdevelopment of the eye and surrounding tissue that causes a small eye and eye socket, or orbit (called orbital hypoplasia)
- a sunken eyeball in the orbit (called enophthalmos)
- changes in the amount and quality of tears made by the eye
- retinopathy or maculopathy, which are vision problems caused by damage or changes to the retina
- damage to the nerves that send messages from the eye to the brain about vision (called optic chiasm neuropathy)
- swelling where the optic nerve enters the eye (called papillopathy)
- enlargement of blood vessels in the sclera, or white of the eye (called telangiectasias)
- inflammation of the cornea, which is the clear outer surface of the eye (called keratitis)
Eye problems may occur as a late effect of some treatments for childhood cancers, including:
- high doses of radiation to the eye, eye socket (called the orbit) or brain
- total body irradiation (TBI) in preparation for a stem cell transplant
- certain chemotherapy drugs such as busulfan (Busulfex)
- surgery to remove an eye
- chronic graft-versus-host disease (GVHD)
- radioactive iodine treatment for thyroid cancer
High doses of radiation may be given to the eye, eye socket or brain to treat retinoblastoma, orbital rhabdomyosarcoma or brain tumours.
TBI and stem cell transplant may be used to treat childhood leukemia, Hodgkin lymphoma, non-Hodgkin lymphoma or retinoblastoma.
Other factors may also increase the risk of developing eye problems as a late effect of treatment, including:
- high blood pressure
- frequent exposure to sunlight
Signs and symptoms of eye problems include:
- not being able to see objects that are nearby
- not being able to see objects that are far away
- double, cloudy or blurred vision
- colours look faded
- poor night vision
- being sensitive to light
- loss of vision
- dry, itchy or burning eyes
- the feeling that there is something in the eye
- watery eyes
- sclera doesn’t look white
- lumps, or tumours, on the eyelid
- drooping eyelid
- small eye and orbit
- sunken eye
Tell your doctor or healthcare team if you or your child develops these symptoms after treatment for a childhood cancer.
An ophthalmologist is a doctor who specializes in diseases of the eye. If you were treated for cancer during childhood, you should be assessed by an ophthalmologist.
Eye problems are usually diagnosed by an eye exam. During an exam, the doctor will:
- put drops in the eyes to dilate the pupils
- use an instrument that shines a narrow beam of light in the eye (called a slit-lamp exam)
- look at the inside of the eye, including the retina and the optic nerve
- take pictures of the eye to keep track of changes in the eye
The ophthalmologist will also examine the inside of the back of the eye using a magnifying lens and light.
Some treatments for childhood cancer put you at higher risk of developing eye problems as a late effect. It is important to protect your vision whether or not you have treatments that may cause eye problems.
You can protect your eyes by doing the following:
- Wear sunglasses with UV protection.
- Use protective eyewear when playing sports, mowing the lawn or doing anything that may get particles or fumes in your eyes.
- Be careful when using hazardous chemicals at home or work.
- Avoid accidents by not playing with things that have sharp parts or parts that stick out and not using fireworks or sparklers.
See your doctor right away if you injure your eye.
Once the extent and cause of an eye problem is known, a treatment plan can be developed. Not all eye problems need to be treated right away or at all.
If vision problems develop as a late effect of treatment for a childhood cancer, it is important to follow the treatment recommendations of the ophthalmologist. If vision is not correctable, you will be referred to services in the community to help people with vision impairment.
Cataracts may not need treatment. Your ophthalmologist will monitor your vision closely and will recommend treatment when it is necessary. Cataracts are treated with surgery to remove the lens and replace it with an artificial one.
Glaucoma may be treated with eye drops, medicines, laser treatment or surgery to reduce the pressure in the eye.
Orbital hypoplasia usually isn’t treated. In severe cases, the doctor may rebuild the bones around the eye.
Enophthalmos may be treated with plastic surgery to build up the eye socket.
Watery eyes may be treated with surgery to widen the tear drainage system if heavy tearing is a considerable problem.
Dry eyes can be treated with artificial tears (eye drops) or ointments to moisten the eye. In severe cases, surgery may be done to block the tear drainage system so that tears aren’t drained from the eye too quickly.
Retinopathy and maculopathy may be treated with photocoagulation. During this procedure, heat or a laser is applied to the retina. In rare and severe cases, surgery is done to remove the eye.
Optic chiasm neuropathy can’t be treated at this time.
Papillopathy may be treated with medicines.
Telangiectasias doesn’t need treatment.
Keratitis may be treated with artificial tears or ointments to moisten the eye. If it is caused by an infection, your doctor will prescribe antibiotic eye drops or ointment. Your doctor may also suggest wearing a patch over the affected eye while you sleep to help with healing. In rare cases, surgery may be done to replace the cornea (called cornea transplant).
All people who are treated for childhood cancer need regular follow-up. The healthcare team will develop a follow-up plan based on the type of cancer, how it was treated and your needs.
If you develop vision problems, you should be seen regularly by an ophthalmologist.
If you have had any of the following, you should have an eye exam by an ophthalmologist at least once a year:
- treatment for a tumour of the eye
- radiation therapy to the eye, eye socket (orbit) or brain
- graft-versus-host disease (GVHD) as a result of a stem cell transplant
If you received radioactive iodine treatment and have too much tearing, you should see an ophthalmologist.
If you have an artificial eye, you should see an ocularist (a person who makes and fits artificial eyes) at least once a year.
A condition that might happen after a stem cell transplant. Healthy stem cells from a donor (called the graft) attack a recipient’s (receiver’s) cells (called the host). The graft cells see the host cells as foreign and start to destroy them. Symptoms include jaundice, rash or blisters on the skin, dry mouth or dry eyes.
What’s the lifetime risk of getting cancer?
The latest Canadian Cancer Statistics report shows about half of Canadians are expected to be diagnosed with cancer in their lifetime.