Nasal Endoscopy – Treatments, risks and more

Nasal endoscopy

Also called: Diagnostic Nasal Endoscopy


Nasal endoscopy is a diagnostic procedure that physicians use to view the inside of the nasal cavity and the entrance to the sinuses. It can be useful in diagnosing conditions such as infections or polyps.

A nasal endoscope is a tube-like instrument that can be rigid or flexible. It is inserted through the nostril after a nasal decongestant or numbing medicine has been applied topically in a patient’s nose. The endoscope is unable to enter the sinus cavities themselves, but it is used to examine the sinus openings.

The endoscope is equipped with small lights and cameras that enable the physician to view and record the terrain of the inner nose. Nasal or sinus-related problems can be identified by viewing the very detailed video or pictures recorded by an endoscope. The endoscope is also capable of taking a tissue sample from inside the nasal cavity that may be used for analysis and further diagnosis.

Nasal endoscopy is very safe, but it is also expensive. It is therefore usually reserved for diagnosing chronic (ongoing) and recurrent rhinosinusitis (sinus infection) and for seeing the differences between allergies and acute sinus problems. There are a number of other circumstances, however, for which a nasal endoscopy may be recommended. For instance, it may be performed to diagnose the cause of the loss of the sense of smell.

A nasal endoscopy does not require any special precautions to be taken prior to the procedure. While the procedure is low-risk, gagging, nosebleeds or coughing may occur as the endoscope is threaded through a nostril. Infection, cerebrospinal fluid leak (leaking fluid surrounding the brain) and excessive bleeding may also occur on rare occasions.

About nasal endoscopy

Nasal endoscopy is a diagnostic procedure that uses an instrument called an endoscope to view the inside of the nose and entrance to the sinuses. It is primarily used to detect abnormalities (e.g., structural defects, polyps, damage to the sinuses). The procedure can also be used to determine if certain surgeries are required or if medications are having their intended effect.

A nasal endoscope (or nasal telescope) is a thin, tube-like optical instrument (2.7 to 4.0 millimeters in diameter) designed to be inserted into the inner nose. It can be rigid and angled or flexible. The nasal endoscopy procedure involves the insertion of the endoscope through the nostrils and up the nasal passageway. Miniature lights in the device illuminate the patient’s nasal passages, nasal cavities and entrance to the sinuses. The endoscope is equipped with fiber-optic cameras that record and display detailed images of the interior of the nose.

Endoscopic cameras allow a physician to view any sinus-related abnormalities. Some endoscopes transmit images to a video screen, which can in some circumstances be viewed by the patient undergoing the procedure. The examination may also be recorded by a digital image archive (similar to a digital camera). Many endoscopes have attachments that allow physicians to remove tissue samples or fluid for further laboratory testing (biopsy).

The procedure is considered very safe and is almost always done without general anesthesia. However, nasal endoscopy is performed only under special circumstances because it is relatively expensive. It is most often used for diagnosing chronic (ongoing) and recurrent rhinosinusitis (sinus infection) or for highlighting the differences between allergies and unrelated sinus problems.

A nasal endoscopy is usually reserved for patients with persistent, chronic symptoms who have not responded to various therapies. Some of the main reasons a physician may order a nasal endoscopy include:

  • To evaluate why a patient is failing to respond to a therapy or medication

  • To determine whether surgery is necessary

  • To examine the results of a sinus surgery

  • To determine the effects of conditions such as severe allergies, immune deficiencies and mucociliary disorders (disorders that affect mucous membranes and cilia)

  • To determine whether a nasal obstruction (e.g., polyps, tumor) is present in the nasal cavity

  • To determine whether any foreign bodies (e.g., small object inserted by a child) are lodged in the nasal cavity

  • To remove a nasal obstruction or foreign material from the nasal cavity  

  • To determine whether an infection has moved beyond the sinuses

  • To diagnose chronic or recurrent rhinosinusitis, particularly in children with asthma

  • To diagnose the reason for anosmia (loss of the sense of smell)

  • To evaluate any unusual discharges from the nasal cavity (e.g., blood, pus, cerebrospinal fluid)

  • To collect fluids or tissue samples for evaluation (biopsy)

  • To diagnose sinus barotraumas (caused by air pressure differences experienced while flying or scuba diving)

  • To evaluate younger children for whom a medical history is considered unreliable

  • To diagnose the reason for facial pain or headaches

The nasal endoscopy will ultimately yield a detailed diagnosis so a physician can determine whether the patient has a condition that requires specific therapy or medication.

In some cases, nasal endoscopy is used in combination with computed axial tomography. Also known as a CAT scan or CT scan, this is a painless test that uses multiple x-ray images, taken from different angles, to create three-dimensional images of body structures. CAT scans enable physicians to view the inside of the sinuses and other structures in the head. When used together, nasal endoscopy and CAT scans provide physicians with a more complete picture of what is occurring in the nose, sinuses and head. This ultimately aids diagnosis and leads to better treatment decisions.   

Before, during and after a nasal endoscopy

Nasal endoscopy is usually performed by an ENT physician (ear-nose-throat physician or otorhinolaryngologist) in the office. There are no special precautions that are required to prepare for the nasal endoscopy but any steps or restrictions that a physician may deem necessary should be followed closely.    

If a physician recommends a sedative for the nasal endoscopy, it is likely the patient will be incapable of driving home after the procedure. If a sedative is to be used, patients should arrange in advance for someone to drive them home.

Once at the office, the patient will dress in a hospital gown and lie down on an examination table. Usually, the ENT or another healthcare professional will spray a topical decongestant, such as a nasal vasoconstrictor, and topical anesthetic (numbing medicine) inside the nose prior to the procedure. The medication has an unpleasant taste and may cause numbness in the teeth and/or throat for 20 to 30 minutes. Patients may also have a temporary sensation of not being able to swallow.

The procedure begins with the careful insertion of a sterile endoscope into a patient’s nostril. In some people, this may stimulate an uncomfortable gag reflex or irritate the lining of the nose sufficiently to cause a nosebleed or coughing. As the endoscope is guided through the nasal passageways, the physician examines the interior of the nose and nasal cavity for any signs that may indicate a problem (e.g., polyps, infections, fungal concretions). While the endoscope is too large to be inserted into the actual sinus cavities, it can be used to effectively examine the entrance to the sinus cavities.

The endoscope is often directed toward one area in particular: the hiatus semilunaris (a crescent-shaped groove that serves as a small channel that drains fluids from the sinuses). This area is typically where problems such as pus, fungus or polyps can be found. Sometimes, an endoscopically directed microswab culture or sample is obtained in this area. Taking a tissue sample is usually painless. The physician will then send the tissue sample to a lab for closer examination.

After the procedure, the endoscope is carefully removed from the nasal cavity and nostril. The patient can typically return to most activities. If an anesthetic was used, the patient may have to wait until the effects wear off to be able to drive, eat or drink. A saline irrigation may be recommended to reduce crusting in the nose and sinus cavity and to keep the sinus openings clear.

If the endoscopy identifies any growths, infections, polyps, defects or pus that interfere with the normal draining of the sinuses, further treatment may be required. The physician will contact the patient to explain any additional measures that need to be taken.

Potential risks of a nasal endoscopy

Nasal endoscopy can be a valuable diagnostic tool for determining the nature of chronic (ongoing) nasal and sinus problems. It provides a very detailed picture of nose and sinus function.

Although considered very safe, several risks or complications can occur on rare occasions. These include:

  • Infection. An infection may develop for various reasons and may require treatment with antibiotics. Drainage that becomes foul smelling, thick or colorful after the procedure may be an indication that an infection has developed or is ongoing. Patients who suspect an infection should contact their physician immediately.

  • Bleeding. Bleeding is not unusual, but excessive bleeding is rare.

  • Cerebrospinal fluid leak. In extremely rare cases, a physician may accidentally make an opening between the sinuses and the brain. The fluid around the brain can then leak into the nasal cavity and out from the nose. This opening increases the patient’s risk of developing meningitis (brain infection).

Treatments that may follow nasal endoscopy

Treatments that follow a nasal endoscopy will depend on what is discovered as a result of the procedure. Polyps, growths, infections or structural defects of the nasal passages are considered abnormal. Surgery, medications or other treatments may be advised after the results of the nasal endoscopy are analyzed. 

Endoscopic sinus surgery may be needed to correct a problem. For instance, it may be used to remove polyps or to correct a deviated septum. Sometimes medication is required to treat an infection or to control allergic reactions. If an allergy is the suspected cause of sinus problems, further tests such as a skin prick test or RAST test may be recommended.

Questions for your doctor

Preparing questions in advance can help patients to have more meaningful discussions with their physicians regarding their conditions. Patients may wish to ask their doctor the following questions regarding nasal endoscopy:

  1. Would I benefit from a nasal endoscopy?
  2. Can you explain the procedure to me in detail?
  3. Will I experience any pain during or after the procedure?
  4. How long will my nasal endoscopy take?
  5. Do I face any risks by undergoing this procedure?
  6. Are there any special steps I should take to prepare for the procedure?
  7. Will an anesthetic or sedative be used?
  8. Will I be able to view the images of my nasal cavity during the procedure?
  9. Am I likely to bleed after the procedure?
  10. What do the results of my nasal endoscopy indicate? Do I require further testing?
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