Nasal Endoscopy

Nasal endoscopy is the direct examination of the nasal cavity, sinus openings and nasopharynx using a thin rigid or flexible telescope with a light source. It is a basic test in the assessment of nasal and sinus disease.

It lets the doctor view areas that cannot be seen by the naked eye with a head light and nasal speculum: the middle meatus, the opening of the sinuses, the olfactory cleft, the back of the nose, and the opening of the Eustachian tube.

A rigid endoscope (2.7 or 4 mm, 0, 30, or 70 degrees) gives a brighter, clearer picture. A flexible endoscope (2.5 to 4 mm) bends to pass narrow or deviated nasal passages and allows examination of the nasopharynx and larynx.

The nose is first treated with a topical decongestant and local anaesthetic spray. The scope is passed along the floor of the nose, between the inferior and middle turbinates, and to the nasopharynx, with views along the way. The test takes 3 to 10 minutes, is done in clinic, and is usually well tolerated.

Nasal endoscopy changes the diagnosis in many patients with symptoms of chronic sinus disease. Symptoms alone are poor at separating chronic rhinosinusitis from other causes of nasal blockage. Endoscopy confirms chronic rhinosinusitis when polyps, mucopurulent discharge, or oedema are seen in the middle meatus.

The diagnosis of chronic rhinosinusitis requires symptoms for 12 weeks or more, together with endoscopic or CT evidence of inflammation.

Indications.

• Nasal blockage, discharge, facial pain or pressure, loss of smell, postnasal drip, and chronic cough, to look for chronic rhinosinusitis, polyps, and structural causes.
• Recurrent or unilateral nosebleeds, to find the bleeding site, tumour, or vascular lesion.
• Suspected nasal or sinus tumour, and unilateral nasal mass or polyp.
• Nasopharyngeal assessment: unilateral middle ear effusion in adults, blocked Eustachian tube, adenoid enlargement, and nasopharyngeal carcinoma.
• Persistent unilateral nasal symptoms, foul smell, or blood-stained discharge.
• Suspected cerebrospinal fluid leak, foreign body, or choanal atresia in children.
• Follow-up after sinus surgery, to remove crusts and check healing.
• Obstructive sleep apnoea, snoring, and voice problems, with assessment of the upper airway.
• Biopsy, culture, and cleaning under direct vision. Not a replacement for CT of the sinuses when surgery is considered.

Contraindications and precautions.

• Few absolute contraindications. Severe nosebleeds that are active, or a bleeding disorder, call for care and preparation.
• Allergy to local anaesthetic or decongestant: alternative agents or no spray are used.
• Uncontrolled hypertension, severe heart disease, or the use of drugs that interact with decongestants (monoamine oxidase inhibitors): caution, since decongestants raise blood pressure and heart rate.
• Recent nasal or skull base surgery or trauma: care to avoid damage.
• Suspected meningocele or encephalocele (a pulsating mass in a child, or a mass in a patient with a cerebrospinal fluid leak): no biopsy before imaging.
• Vascular tumours (juvenile angiofibroma) and suspected carotid artery abnormalities: no biopsy before imaging.
• Patients who are anticoagulated may bleed, and the scope is passed gently.
• A fear of the test in children: explanation, distraction, and sometimes sedation. The equipment is cleaned and disinfected following infection control rules after each use.

Preparation and technique.

The patient sits upright with the head supported. The nose is sprayed with a decongestant and a local anaesthetic, and a few minutes are allowed for the effect. The examination follows a fixed sequence.

The scope is first passed along the floor of the nose to view the inferior turbinate, the nasal floor, and the nasopharynx, with the opening of the Eustachian tube and the lateral nasopharyngeal recess.

It is then passed between the inferior and middle turbinates, and then along the roof of the nose to view the sphenoethmoidal recess, olfactory cleft, and middle meatus. This includes the opening of the maxillary sinus, the uncinate process, and the bulla.

The septum, any deviation or spur, mucosal colour, secretions (clear, mucoid, purulent), polyps, crusting, and masses are noted. Photographs or video are saved. Biopsy and swabs can be taken. The procedure is explained, and the patient is asked to breathe through the mouth if there is gagging.

Normal appearances.

The mucosa is pink, moist, and smooth, with small amounts of clear secretions. The septum is mostly midline, and the turbinates are of normal size. The middle meatus is open and free of discharge, polyps, or swelling. The nasopharynx has a smooth lining, and the Eustachian tube openings are symmetrical, with the adenoid tissue small in adults. The olfactory cleft is open.

Interpretation.

• Chronic rhinosinusitis without polyps: oedema, mucopurulent discharge from the middle meatus, and mucosal inflammation.
• Chronic rhinosinusitis with polyps: pale, grey, smooth, mobile grape-like swellings from the middle meatus, usually bilateral. They are graded by size (grade 1 limited to the middle meatus, 2 reaching lower than the middle turbinate, 3 reaching the floor of the nose).
• Allergic rhinitis: pale, bluish, swollen turbinates with clear watery secretions.
• Deviated septum or spur: contact with the lateral wall, causing blockage and, at times, headache or bleeding.
• Unilateral polyp or mass, friable or bleeding, ulcerated, or with bone destruction: suspected tumour (inverted papilloma, squamous cell carcinoma, adenocarcinoma, lymphoma, or other).
• Nasopharyngeal mass, asymmetry of the lateral nasopharyngeal recess, or blocked Eustachian tube opening: suspected nasopharyngeal carcinoma.
• Enlarged adenoids: nasal blockage and ear effusion in children.
• Crusting and atrophy: atrophic rhinitis, granulomatous disease, drug effects (cocaine), or previous surgery.
• Clear fluid dripping with a mass: cerebrospinal fluid leak or encephalocele.
• Bleeding point, prominent vessels, or telangiectasia: epistaxis site, hereditary haemorrhagic telangiectasia.

Critical values and findings needing immediate action.

• Unilateral friable mass, ulcer, or bleeding lesion: urgent biopsy by a specialist and imaging for suspected malignancy.
• Pulsatile mass or suspected encephalocele or cerebrospinal fluid leak: no biopsy, and urgent imaging and neurosurgical advice.
• Posterior epistaxis with active bleeding and haemodynamic compromise: emergency resuscitation and packing or cautery.
• Necrotic black or grey tissue in the nose of a diabetic or immunosuppressed patient: urgent assessment for invasive fungal sinusitis, with imaging and surgical debridement.
• Orbital swelling, vision loss, or severe headache with sinusitis: urgent imaging for orbital or intracranial complications.
• Septal haematoma or abscess after trauma: urgent drainage.

Limitations and artefacts.

• Decongestants shrink the mucosa and can hide or change the signs of inflammation. Poor topical anaesthesia and anxiety limit the view.
• Narrow passages, a marked deviation, or a large spur can block the scope, so a thinner flexible scope is used.
• The sinuses themselves cannot be seen, only their openings, so the test does not replace CT for the extent of disease.
• Endoscopic appearances and symptoms correlate poorly in some patients, and mucosal swelling in viral infection and allergy can mimic chronic disease.
• Inexperience leads to missed lesions at the back of the nose, and the nasopharynx is a blind spot for the beginner.
• Complications are uncommon, and include discomfort, nosebleed, vasovagal faint, and rarely allergic reaction, and rarely injury.
• Biopsy in the wrong setting (vascular tumour, encephalocele) can lead to serious bleeding or leakage.

Special groups.

• Children: flexible thin scopes after topical anaesthesia, with parental help. Adenoid hypertrophy, foreign body, choanal atresia, and encephalocele are considered.
• Pregnant women: the decongestants are used sparingly.
• Patients with bleeding disorders or on anticoagulants: caution and local control of bleeding.
• Patients with suspected nasopharyngeal carcinoma: persistent unilateral ear effusion, neck mass, and nosebleeds, with biopsy of the nasopharynx.
• Immunosuppressed and diabetic patients: early examination in facial pain or black nasal discharge.
• Regions: nasopharyngeal carcinoma is common in parts of East Asia, South East Asia, and North Africa, and endoscopy is a key diagnostic tool. A head light and rigid scope can be used in clinics with low resources. Chronic rhinosinusitis, allergic rhinitis, nasal polyposis, fungal sinusitis, and trauma are common reasons for visits.

Follow-up tests.

• CT of the sinuses and skull base for the extent of disease and before surgery.
• MRI of the nasopharynx, skull base, and sinuses for tumours.
• Biopsy and histology of suspicious lesions.
• Allergy tests (skin prick tests, specific immunoglobulin E), and blood eosinophil count.
• Smell testing, and cultures of purulent discharge.
• Tests for granulomatous disease (antineutrophil cytoplasmic antibodies, angiotensin-converting enzyme) and immune deficiency in refractory disease.
• Nasal function tests (rhinomanometry) in blockage.