Tests for eye cancer (ocular melanoma)

You may have tests to diagnose eye cancer (ocular melanoma), to help plan your treatment or to check how effective it has been.

Tests to diagnose eye cancer

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.

Colour photography

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.

Optical coherence tomography (OCT) scan

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.

Ultrasound scan

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.

Eye angiography

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.

Fine needle biopsy

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.

Further tests for eye melanoma

You usually have other tests to find out more about the size and position of the eye melanoma and whether it has spread. Some of the tests might depend on the type of eye melanoma you have.


If you have uveal melanoma, you may have a liver ultrasound.

If you have conjunctival melanoma, you may have an ultrasound of the neck lymph nodes.

These are the areas of the body the eye melanoma is more likely to spread to.

MRI scan

An MRI scan uses magnetism to build up a detailed picture of the inside of your body. It can be used to find out the size of an eye melanoma and whether it has spread nearby or to other parts of the body.  

Blood tests

If you have uveal melanoma, you may have blood tests to check how your liver is working.

About our information

  • References

    Below is a sample of the sources used in our eye cancer (ocular melanoma) information. If you would like more information about the sources we use, please contact us at cancerinformationteam@macmillan.org.uk

    Jain P, Finger PT, Fili M, et al. Conjunctival melanoma treatment outcomes in 288 patients: a multicentre international data-sharing study. British Journal of Ophthalmology 2021;105:1358–1364. (accessed May 2022).

    Nathan, Paul, Hassel, Jessica C, et al. Overall Survival Benefit with Tebentafusp in Metastatic Uveal Melanoma. New England Journal of Medicine, 2021, 385(13):1196-1206. (accessed May 2022).

    Jessica Yang, Daniel K. Manson, et al. Treatment of uveal melanoma: where are we now? Therapeutic Advances in Medical Oncology. 2018, Vol. 10: 1–17. (accessed May 2022).

  • Reviewers

    This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert medical and health professionals and people living with cancer. It has been approved by Senior Medical Editor, Dr Samra Turajlic, Consultant Medical Oncologist.

    Our cancer information has been awarded the PIF TICK. Created by the Patient Information Forum, this quality mark shows we meet PIF’s 10 criteria for trustworthy health information.

The language we use

We want everyone affected by cancer to feel our information is written for them.

We want our information to be as clear as possible. To do this, we try to:

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We use gender-inclusive language and talk to our readers as ‘you’ so that everyone feels included. Where clinically necessary we use the terms ‘men’ and ‘women’ or ‘male’ and ‘female’. For example, we do so when talking about parts of the body or mentioning statistics or research about who is affected.

You can read more about how we produce our information here.

Date reviewed

Reviewed: 01 October 2022
Next review: 01 October 2025
Trusted Information Creator - Patient Information Forum
Trusted Information Creator - Patient Information Forum

Our cancer information meets the PIF TICK quality mark.

This means it is easy to use, up-to-date and based on the latest evidence. Learn more about how we produce our information.