Transnasal oesophagoscopy (TNO)

A transnasal oesophagoscopy is a test using a flexible tube with a camera at the end (an endoscope). Your doctor looks for changes or abnormal areas inside your:

  • throat

  • voice box (larynx)

  • upper part of the food pipe (oesophagus)

The endoscope passes through one side of your nose and into the back of your throat. 

You might also hear this called a TNO. You usually have this test as an outpatient. 

You might have this test if you have: 

  • difficulty swallowing

  • problems with your voice

  • pain in and around your throat

  • a feeling there is something in your throat

Why do you have a transnasal oesophagoscopy?

You might have it instead of having an endoscopy with a general anaesthetic Open a glossary item. This might happen if you aren't well enough to have a general anaesthetic.

How to prepare for a transnasal oesophagoscopy

Tell your doctor if you're taking any medicines. If you take blood thinning medicine your doctor will ask you to stop these a few days before the test. Your doctor will also tell you if you need to stop taking any other medicines. You should also let your doctor know of any allergies you have. 

You must not eat for 4 hours before the test. Talk to your doctor if not eating could be a problem for you. For example, if you have diabetes.

Your doctor or nurse will explain the test and might ask you to sign a consent form. This is a good time to ask any questions you might have.

How do you have a transnasal oesophagoscopy?

The test usually takes about 10 to 15 minutes. But it might be longer if your doctor needs to take a biopsy Open a glossary item. You usually sit in a chair to have this test. 

When you are comfortable your doctor uses an anaesthetic spray to numb your throat. It takes a few minutes for the area to go numb.

The doctor then passes the long, flexible endoscope through your nose and into your throat and food pipe. It can feel uncomfortable but it shouldn’t be painful.

The endoscope has a light and a video. This gives your doctor pictures of the inside of the throat, voice box and upper part of the food pipe. They check for any growths or abnormal areas. 

To help the doctor have a clear view they might pass a small amount of air or suck up fluid from the food pipe through the flexible tube. This may make you burp, which is normal.

You will be able to breathe, swallow and cough normally during the test.

Having a biopsy

Your doctor may need to take a biopsy during the test. They can do it at the same time as the test. Your doctor sends the samples to the laboratory where a specialist doctor called a pathologist looks at them under a microscope.

Some people might need a biopsy under a general anaesthetic. You will be admitted to hospital on a different day if you need this. Your nurse will give you more information about going into hospital.

What happens after a transnasal oesophagoscopy?

You can usually go home soon after the test. Your doctor may ask you to stay in the department for a little while afterwards. 

Ask your nurse or doctor when you can start taking your blood thinning medication again.  

Possible problems

A transnasal oesophagoscopy is a safe procedure but as with any medical procedure, there are possible risks. Your doctor makes sure the benefits of having this test outweigh any possible risks.

Your throat and nose will stay numb for a while after the test. You should not eat or drink for two hours after the test. You might also feel bloated, pass wind, or burp for a while afterwards. This is normal and will pass after an hour or two. 

Your nurse will let you know about any specific instructions you need to follow after the test. 

You might have some bleeding afterwards if you have a biopsy. You might notice some blood in your saliva. This usually settles. Call your advice line if you are spitting up bright red blood or your bleeding continues or becomes heavy.

Contact your hospital advice line immediately or visit Accident and Emergency if you:

  • have breathing problems such as shortness of breath

  • have a temperature over 38 degrees

  • have chest pain

Getting your results

The doctor can record the test and then replay the recording slowly. They will explain to you the findings of the test.

If you have a biopsy should get your results within 1 to 2 weeks.

Waiting for results can make you anxious. Ask your doctor or nurse how long it will take to get them. Contact the doctor who arranged the test if you haven’t heard anything after a couple of weeks.

You might have contact details for a specialist nurse who you can contact for information if you need to. It may help to talk to a close friend or relative about how you feel. You may want them to go with you to get the results for support.

For information and support, you can call the Cancer Research UK nurses on freephone 0808 800 4040. The lines are open from 9am to 5pm, from Monday to Friday.

  • Extended role of transnasal oesophagoscopy: A review of the literature

    L Johnstone and others

    The Journal of Laryngology and Otology, 2020. Volume 134, Issue 6, Pages 481- 486

  • Improving outcomes in head and neck cancers 
    National Institute for Health and Care Excellence, November 2004. Updated 2015 (accessed July 2024).

Last reviewed: 
15 Jul 2024
Next review due: 
15 Jul 2027

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