Definition & Overview
A nasoendoscopy is a diagnostic procedure that examines the nasal passage, throat, and larynx or voice box. It uses an endoscope, a specialised telescopic instrument that is guided into the nasal passage until the bottom of the throat to collect detailed images or videos of the said structures.
An endoscope is composed of many small parts that serve to provide visual imaging of internal body parts. The tube, which could either be flexible or rigid, provides support and structure to the device and its components. Its end is usually fitted with an optical fibre light system to provide illumination. The built-in lens, on the other hand, is responsible for capturing images of the internal body structures and relaying these images to a monitor. In some cases, an endoscope is fitted with an eyepiece to allow the surgeon to view the images directly. An endoscope also serves as a vehicle for other medical instruments that need to be inserted during the procedure. This requires the presence of an additional channel within the endoscope to accommodate these instruments.
The endoscope is a useful tool for diagnosing any abnormal growth or condition inside the nasal passage.
Who Should Undergo and Expected Results
Nasoendoscopy is advised for patients who experience recurring conditions involving the nose or throat. These include:
- Recurrent nosebleeds
- Chronic sinusitis – In this case, nasoendoscopy is performed to examine the nasal passages to better understand the condition and formulate effective treatment
- Nasal polyps - These abnormal growths form inside the nose and sinuses and are often due to allergic reactions or asthma
- Dysphonia - This disorder is characterised by the impaired production of voice sounds, resulting in harsh, rough, and extremely breathy phonation. This is caused by the inability of the voice box to vibrate properly during exhalation.
- Dysphagia, or difficulty in swallowing - This condition can be caused by growths along the oesophagus, oesophagal stricture, or muscular disorder in the affected area.
- Suspected cancer of the nose, throat or larynx - Nasoendoscopy could help determine any abnormal growth along the linings of the nasal passage as well as harvest several tissue samples for biopsy.
Those who are complaining of ingesting or inhaling any foreign body in the throat or nose are also advised to undergo this procedure as an immediate intervention.
Nasoendoscopy is a simple, outpatient procedure that lasts only for several minutes. The images and video taken from this procedure are used not just to make a diagnosis but also to determine the most appropriate treatment for the diagnosed condition. Patients are then asked to return to the physician’s clinic for further evaluation and consultation.
How is the Procedure Performed?
In preparation, patients are usually administered with a nasal decongestant and, if needed, local anaesthesia. They remained seated during the course of the procedure to allow easy manipulation of the head.
The endoscope is inserted into the nasal cavity and guided into the nasopharynx. The physician will take note of the surrounding structures as the scope proceeds, trying to determine any abnormality. After examining the entire nasopharynx, a second pass is made with the endoscope guided between the middle and inferior turbinate to take images of these structures and surrounding parts. For the third pass, the physician may require the patient to turn their head to allow easy evaluation of the olfactory cleft. A different type of endoscope may also be used for better visualisation. The scope is then used to determine the presence of any lesion or polyp. If there is a need, tissue samples are also collected in some parts of the nasal cavity.
The patient may be asked to talk, swallow, puff their cheeks, or extend out the tongue as the endoscope is manipulated inside the nasal cavity.
Possible Risks and Complications
Risks and complications of nasoendoscopy are rare and are often not serious. These include:
- Adverse reaction to local anaesthesia used; manifested in discomfort or difficulty in breathing
- Bleeding, particularly among patients with a history of bleeding disorders. It can also occur due to the harvesting of a nasal tissue sample.
- Soreness in the throat – This is very common and typically resolves on its own after a few days even without treatment.
- Sneezing - In some instances, the insertion of the endoscope into the nasal cavity induces an episode of sneezing.
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Ferguson BJ, Narita M, Yu VL, Wagener MM, Gwaltney JM Jr. Prospective observational study of chronic rhinosinusitis: environmental triggers and antibiotic implications. Clin Infect Dis. 2012 Jan 1. 54(1):62-8.