Flexible Nasopharyngoscopy

Article Author:
Sirhan Alvi
Article Editor:
Pooja Harsha
Updated:
8/8/2020 11:32:39 PM
PubMed Link:
Flexible Nasopharyngoscopy

Introduction

Flexible nasopharyngoscopy (also called fiberoptic nasendoscopy/flexible nasolaryngoscopy/flexible fiberoptic nasopharyngolaryngoscopy) is an essential skill for any otorhinolaryngologist (ENT surgeon). It is a diagnostic procedure used for examination of the nose, throat, and airway. Fiberoptic imaging became prominent in the 1950s due to the innovations of Hopkins and Stortz. The first medically functioning fiberoptic scope was designed in 1963 by Hirschowitz.[1]

Anatomy and Physiology

Nasopharyngoscopy can be performed in adults, cooperative children, and babies with parental permission. It is typically done to investigate any area of concern or follow-up in a treated area (surgery/radiotherapy/chemotherapy) that is otherwise difficult to access and visualize.

As there are too many abnormalities and pathologies that are identifiable on scoping, that to mention all would be impossible. Some of the important and commoner ones are listed below.

Nasal Cavity

A three-pass technique is used to examine all areas of the nasal cavity.

  • Septal deviation, bony spurs, turbinate hypertrophy
  • External and internal nasal valve areas
  • Nasal obstruction, mucopurulent debris, sinus drainage, mucosal edema
  • Bleeding points, septal perforations
  • Polyps, adhesions, and crusting 

Posterior Nasal Space

The Eustachian tube orifices, fossa of Rossenmuller, and adenoidal pad are inspected.

Adenoids should regress in adulthood, and prominent adenoids warrant investigation. Any untoward mass seen should be further investigated.   

The Base of Tongue and Valleculae

The base of tongue and valleculae are inspected for any masses, cysts, or irregularities. Lymphoid tissues of the lingual tonsils can be found here and often account for the irregularity seen. Any untoward mass seen should be further investigated, as this is a common site for oropharyngeal squamous cell carcinoma.

Epiglottis

In children, abnormalities of the epiglottis (omega-shaped) and aryepiglottic folds can be seen in laryngomalacia.[2]

Epiglottitis is a contraindication for scoping, unless done in experienced hands in a stabilized patient in an appropriate environment, due to the risk of laryngospasm and airway deterioration. 

Piriform Fossae

Any pooling of saliva, fullness, or masses seen here requires further investigation.

Larynx

Abnormalities of the arytenoids, if any, should be inspected.

Vocal cord movements, swelling, edema, masses, or mucosal changes also require examination. Any stridor or airway concerns again need to be scoped in a safe environment and experienced hands, with support from the anesthetists.

Indications

The majority of scope investigations occur in the hospital setting for acute assessments of the airway, persistent hoarseness, globus sensation, recurrent epistaxis, and tumor/cancer investigation and surveillance. In addition to this, the other main indications are listed below:[3][4][5][6]

  1. Removal of a foreign body that is easily accessible
  2. Evaluation of obstructive sleep apnea, e.g., the Muller maneuver, although it is still difficult to evaluate from this the patients that will do well with surgery.
  3. Velopharyngeal insufficiency
  4. Examining the acute airway and establishing if patients require intensive therapy unit (ITU) care or airway management
  5. Fibre endoscopic evaluation of swallowing (FEES) done in association with the speech and language therapists in patients with swallowing problems
  6. Vocal cord office-based injections for vocal cord palsies
  7. Tracheoscopy

Contraindications

There are few contraindications for flexible nasopharyngoscopy. The main two are acute epiglottitis and croup. In epiglottitis, there is an actual risk of sending the patient into laryngospasm, so this needs to be left to an experienced ENT surgeon to perform the procedure if required.[7] Relative contraindications include coagulopathies, which may result in significant bleeding and craniofacial trauma where inadvertent intracranial instrumentation can occur.

Equipment

  • Flexible nasopharyngoscope - fibreoptic or digital chip-on-the-tip technology; the size of scope diameter varies from 1.9 mm (pediatric) to 6 mm (adult)
  • A viewing camera can be attached to the viewing port of the scope (if not a digital scope)
  • A light source (can be portable) 
  • Light lead (if required)
  • Screen/monitor with picture acquisition and an image printer
  • A decontamination system for scopes: a disposable endoscopic sheath; chlorine dioxide multi-wipe system; endoscope washer-disinfector units
  • Topical decongestant/anesthetic spray
  • Lubrication gel
  • Alcohol wipes
  • Tissues

Personnel

  • ENT surgeon
  • Maxillofacial surgeon
  • Speech and language therapists (fiberoptic evaluation of swallowing)

Technique

Preparation

  • The nasopharyngoscope should be cleaned and disinfected. Follow the clinic or hospital policy.
  • If using an endoscopic sheath apply it
  • Confirm the light source and light lead are functioning normally
  • Discussion with the patient should include the following:
    • The need for the procedure
    • Describe the procedure
    • Discuss the risks, including the discomfort. It may cause them to sneeze and their eyes water. The local anesthetic spray has a very very bitter taste and rarely may cause a reaction. They should be NPO for an hour.
    • Discuss the benefits including diagnosis
    • Obtain the patient's informed consent 
  • Positioning
    • The patient should sit upright, "sniffing the morning air." The head should be supported 
  • In most cases, use a topical nasal anesthetic spray as the procedure is poorly tolerated with this by most patients.
  • Lidocaine and epinephrine or xylometazoline can help to numb and decongest the nose if there is mucus or edema. 

Pass the Nasopharyngoscope

  • Have the patient sniff and observe which nasal passage is the more patent.
  • Visualize both nasal passages, especially for nasal conditions
  • The posterior nasal space, the base of the tongue, hypopharynx, and larynx can be examined by using one side.
  • Focus the lens using some writing or a label
  • Lubricate the scope and avoid getting any lens
  • Fogging can be reduced with the patient's saliva or isopropyl alcohol.
  • Direct the scope at the center of the lumen without touching the sides. This can pick up debris. The lateral nasal wall is less sensitive.
  • Ask the patient to breathe normally through their nose when moving from the nasopharynx to oropharynx. This allows the soft palate to open up and allows the scope to be advanced without resistance.

 Examination[8]

  • Examine the nose, posterior nasal space, the base of tongue, pharynx, and larynx 
  • Visibility can be improved by having the patient do the following:
    • Protrude the tongue to visualize the tongue valleculae and base.
    • Puffing the cheeks gives a better view of the pyriform fossae - alternatively moving the head to the right and left will do the same.
    • Observe vocal cord movements by having the patient make an 'Eeeee' sound or counting aloud will abduct both vocal cords at the midline normally. Breathing should abduct the cords equally.
  • Foreign bodies can be removed with handheld forceps using the scope for visual guidance.

 Communication

  • Record findings in the medical record

A simple drawing is useful. Most medical record systems will allow picture capture and printing. This permits the medicolegal documentation of findings and allows comparison of findings between visits. Some departments require a separate procedural log to be noted, which allows for correct tariffs to be billed and allows traceability. The cleaning or traceability sticker from the nasopharyngoscope should be part of the medical record.

Post-procedure Instructions

  • The patient should be NPO until the anesthetic spray effects have resolved. Depending on the agent used, this is usually an hour.
  • The patient's vital signs should be assessed, and they should remain seated until they can ambulate safely.
  • At the end of the scope procedure, follow endoscope sterilization procedures.

Complications

The following represent some of the possible comlications[9][10][11]:

  • Although complications are rare, the most common are sneezing, and mucosal tearing and bleeding secondary to injury - to prevent this, adequate nasal decongestion and limited force should be used
  • Laryngospasm, a serious risk, although reported in less than 1% of procedures
  • Gagging and adverse reaction to the nasal decongestant are other potential risks
  • Damage to anatomic structures is more common with the use of rigid scopes, and rarely seen with flexible scopes

Clinical Significance

Flexible nasopharyngoscopy and fiberoptic imaging have revolutionized ENT outpatient clinics. Technology has moved further forward with the new chip-on-the-tip digital flexible scopes. This method is a far cry from the ENT doctors using indirect laryngoscopy with hand-held mirrors and head mirrors.

In a typical head and neck cancer clinic, nearly all patients will have a flexible nasopharyngoscopy to look at cancer surveillance, treatment response, or disease recurrence. In the acute setting, it is also used very often, for example, in all airway concerns or neck abscesses. It has become a routine tool in the ENT surgeon's armament, as common as using an otoscope, and one that is used regularly.

Enhancing Healthcare Team Outcomes

Interpretation and ability to carry out flexible nasopharyngoscopies remains a skill and a learning curve. Although the ENT surgeon does these procedures daily, and so their learning curve is much faster, other related specialists, including anesthesiologists, nurse anesthetists, and the pulmonologists, can use this tool and quickly pick up the expertise also. New gadgets used in stroboscopy, digital chip-on-the-tip technology, and endoscopic smartphone adapters keep the technology moving forward.[12][13][14]


References

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