Sight after nasopharyngeal cancer treatment

Some people with nasopharyngeal cancer have problems with sight (vision). Problems include weakness of the eye muscles, double vision or rarely, sight loss in one eye. These changes can be difficult to cope with.

Who might have sight problems?

Only some people with nasopharyngeal cancer have problems with sight (vision).

The more advanced the cancer, the more likely it is to affect your sight. Unless you were diagnosed in the early stages of nasopharyngeal cancer, it might have spread to:

  • the nerve that controls eye movement
  • the eye
  • tissue surrounding the eye

Double vision

Cancer affecting the cranial nerve that controls eye movement can cause double vision. But this only affects around 10 in every 100 people diagnosed with nasopharyngeal cancer (around 10%).

This often improves after treatment with radiotherapy and chemotherapy. There may be treatments your doctor can suggest to improve your vision if symptoms continue. It may be possible to correct it with glasses.

Tell your doctor if you start to get double vision after having treatment for nasopharyngeal cancer. In some cases, it may be due to a late side effect of radiotherapy or a sign that the cancer may have come back.

Other changes

You might have other changes in your vision if your cancer is affecting your eye socket. Or you might completely lose the sight in one eye. But this is rare.

If you have any problems with your eyesight, you will have regular appointments with an eye specialist.


Any change to your sight can be difficult to cope with. Your treatment team will help support you.

You can read more about coping with changes to your sight in our section about nasal and paranasal sinus cancer. Remember that not all the information there will apply to you.

Cancer Research UK nurses

For support and information, you can call the Cancer Research UK information nurses. They can give advice about who can help you and what kind of support is available. Freephone: 0808 800 4040 - Monday to Friday, 9am to 5pm.
Last reviewed: 
25 Feb 2021
Next review due: 
25 Feb 2024
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