Tests for eye cancer (ocular melanoma)

You may have some of the following tests to diagnose eye cancer. Your specialist eye doctor (ophthalmologist) or nurse will give you more information and tell you what to expect. 

Before or during some tests, the doctor may put drops in your eye. These widen the black part in the middle of your eye (pupil). This makes it easier for the doctor to check the inside of your eye. The drops make your eyesight blurry for a few hours, and you might find bright lights uncomfortable. Do not drive until your eyesight returns to normal.

In this test, special cameras take photographs of the front or back of your eye. This is to help find the cause of your symptoms. You may also have this test to compare the tumour before and after treatment.

This scan uses light waves to produce images of the retina and choroid. You sit in front of the OCT machine and place your head on a support. This keeps you still while the back of your eye is scanned. The scan takes 10 to 15 minutes.

An ultrasound scan uses sound waves to build up a picture of the inside of your eye and surrounding areas. The doctor gently presses a small probe against your closed eyelid and moves it over the skin. The probe produces sound waves. A computer converts the sound waves into an image on a computer screen. 

An ultrasound is painless and usually only takes a few minutes. Sometimes the probe is placed directly on your open eye. You will have eye drops to numb the area before this is done.

If you need surgery, this test shows exactly where in the eye the melanoma is. It helps doctors plan the operation. During the test, a doctor turns down the lights in the room and shines a very bright light into your eye to look for abnormal areas.

This test examines the blood vessels at the back of your eye (retina). Before the test, you have drops put in your eye to widen your pupil. A doctor then injects a dye into a vein in your arm. This shows up the blood vessels in the retina. You may feel warm or flushed for a short time after the injection.

The doctor will take lots of photographs of the back of the eye before and after you have the dye. After the test, your skin may have a yellow tint and your pee (urine) may be darker than usual. This is caused by the dye. It is harmless and only lasts a few days.

This is when a doctor uses a very fine needle to remove a sample of cells from the affected area of the eye. It is done by expert eye doctors who can do it safely and efficiently. You may have a local anaesthetic or general anaesthetic.

The sample is sent to a laboratory, to a doctor (called a pathologist) who specialises in studying cells. They look at the sample under a microscope to check for melanoma cells. They may also check for genetic changes in the melanoma cells. This can tell your doctor whether certain cancer drugs would be helpful if the melanoma has spread.

A biopsy is not usually needed to diagnose eye melanoma. Other tests can be used. A biopsy is not usually done for conjunctival melanoma. It may increase the risk of the melanoma cells spreading.

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