Flexible Fiber-Optic Nasolaryngoscopy

T. S. Lian, MD FACS
Email

Send Email

Recipient(s) will receive an email with a link to 'Flexible Fiber-Optic Nasolaryngoscopy' and will have access to the topic for 7 days.

Subject: Flexible Fiber-Optic Nasolaryngoscopy

(Optional message may have a maximum of 1000 characters.)

×


Introduction

Flexible fiber-optic nasolaryngoscopy is useful technique to allow for a thorough examination of the hypopharynx and larynx. As the fiber-optic endoscope is passed through the nasal cavity and the nasopharynx, these areas are easily examined as well. Direct examination of the areas can provide for a more thorough examination as opposed to indirect techniques such as mirror examination as well as more limited examination using a nasal speculum. 
A thorough understanding of the anatomy of the nasal cavity, nasopharynx, hypopharynx, and larynx is necessary in order to completely realize the utility of flexible fiber-optic nasolaryngoscopy. Anatomical structures that can be identified and used as landmarks for orientation when passing the scope via the nasal cavity include the floor of the nose, nasal septum, and inferior turbinate. Similarly, familiarity with the nasopharyngeal opening of the eustachian tubes and posterior nasopharyngeal wall as well as the nasal side of the soft palate is necessary when advancing the scope. 
Flexible fiber-optic nasolaryngoscopy is not only useful in the identification of pathology such as masses, but it is also a dynamic examination, as the movement of the soft palate and the vocal cords can be assessed. Another useful feature of flexible fiber-optic nasolaryngoscopy is that a recording of the exam can be made when the scope is attached to a camera. This documentation is useful, as previous examinations can be reviewed and compared. 

Equipment

  • Numerous flexible fiber-optic laryngoscopes are available; however, they all have basic common features, including a monocular eye piece for viewing; hand piece with controls to flex the tip of the scope; and the fiber-optic bundle, which is inserted during examination. The diameter of most fiber-optic bundles range from 3 to 4 mm, with the working length typically being up to 300 mm. A light source is also required.

Indications

  • Odynophagia

  • Dysphagia

  • Hemoptysis

  • Dysphonia (hoarseness)

  • Dyspnea

  • Stridor

  • Epistaxis

  • Chronic nasal airway obstruction

  • Foreign body

  • Unilateral serous otitis media in an adult

Contraindications

  • Uncooperative patient

  • Intractable bleeding

  • Impeding airway collapse

  • Suspected epiglottitis/supraglottitis in a child

The Procedure

Step 1

Obtain informed consented. Ask the patient if breathing is better through one side of the nose relative to the other. If there is a perceived difference, one should plan on introducing and passing the scope through the side of the nose that is easier to breathe through. Topical decongestant spray such as phenylephrine (Neo-Synephrine) or oxymetazoline (Afrin) as well as an anesthetic such as 4% topical lidocaine is insufflated into the nasal cavity. Benzocaine spray can also be sprayed into the oral cavity and oropharynx for further anesthetic effect. 
  • PITFALL: The lidocaine solution has a bitter taste. Warn the patient about this unpleasant effect. The examiner should pause for a few seconds after administering the first two sprays to allow the anesthetic to take effect and to permit the patient to respond to the taste.

Step 2

The scope is typically held with the dominant hand guiding the fiber-optic bundle and the nondominant hand holding the eyepiece end of the scope and operating the flexion/extension control. 

Step 3

The thumb is used to slide the deflection control to cause the tip of the scope to deflect up or down. Strong twisting action of the right first and second fingers torque the scope tip from its vertical motion to the right and left, and continued up-and-down movement of the left thumb facilitates right and left turning. 

Step 4

The patient assumes and maintains a sitting, upright “sniffing” position with the neck slightly extending, allowing for the chin to be slightly elevated. 
  • PITFALL: A patient’s glasses can interfere with anchoring the hand to the patient’s face or be hit during the procedure. Consider asking the patient to remove glasses before the procedure.

Step 5

The flexible end of the scope is then introduced into the nasal vestibule. The dominant hand advances and guides the fiber-optic bundle while using the patient’s external nose for stabilization. It is imperative from this point on until the scope is removed that the operator look through the eyepiece so as to avoid traumatizing the patient. One should avoid blindly advancing or withdrawing the scope. The floor of the nose, anterior nasal septum, and anterior extent of the inferior turbinate should be identified for reference prior to advancing the scope. The figure shows the anterior nasal septum, floor of the nose, and anterior face of the inferior turbinate. 

Step 6

The scope is then advanced along the floor of the nose toward the nasopharynx. The nasal side of the soft palate, uvula, ipsilateral eustachian tube opening, and posterior wall of the nasopharynx should be identified (as in the figure) for reference. Motion of the soft palate can be assessed by having the patient say “kick, cat, cow” or “K-K-K-K-K.” The flexion/extension control can be manipulated so that the contralateral eustachian tube opening can also be examined. The figure shows the torus tubarus (opening of the eustachian tube os) and nasal surface of the soft palate, and the posterior wall of the nasopharynx is identified prior to flexing the tip of the scope and passing into the hypopharynx for examination of the larynx. 
  • PITFALL: During insertion of the endoscope, mucus can adhere and obscure the view through the scope. Gently tap the tip of the scope against the wall of the nasopharynx to clean the view on the scope. If the view becomes obscured while examining the larynx, have the patient swallow to clear the tip of the scope. It is almost never necessary to completely withdraw the scope to clear the lens.

Step 7

With the posterior wall of the nasopharynx in view, the tip of the scope is flexed down, and the scope is advanced into the oropharynx and hypopharynx. In this position, numerous anatomical structures can be examined to include the base of tongue, vallecula, lateral and posterior pharyngeal walls, epiglottis, aryepiglottic folds, arytenoids, true and false vocal folds, and the glottic aperture (and to a certain extent, the pyriform sinuses and subglottis). The vallecula and base of tongue may be better seen by having the patient stick out the tongue. Normal true vocal cords should appear white relative to the other more pink mucosal surfaces. The free edge of the true vocal cords are smooth and linear in the normal situation. Any irregularity in this area, such as a mass, would be expected to affect the normal vibratory nature of the true vocal cords and result in hoarseness. Assessment of true vocal cord motion can be made by having the patient say “eeee.” In the normal circumstance, the true vocal cords approximate to the midline on phonation. Acute unilateral true vocal cord paresis or paralysis/immobility can result in incomplete approximation of the true vocal cords with a resultant weak and breathy voice. Frank aspiration of secretions may also be observed in the setting of unilateral vocal cord paralysis. Further assessment of true vocal cord abduction can be made by having the patient sniff in through the nose. In the absence of bilateral true vocal cord abduction, the patient may experience an element of stridor and/or dyspnea, which may require urgent securing of the airway, particularly in the acute setting of bilateral vocal cord paralysis. The posterior glottis should also be examined, as this area commonly appears thickened and relatively pale in cases of chronic laryngopharyngeal reflux or relatively erythematous in the acute situation. The procedure is completed by withdrawing the scope while looking through the eyepiece until the end of the scope has exited the nose. 

Complications

  • Mucosal abrasion

  • Bleeding

  • Laryngospasm

Pediatric Considerations

Flexible fiber-optic nasolaryngoscopy can be performed in children depending on cooperativity and availability of pediatric/neonatal flexible laryngoscopes. Such scopes have a relatively small fiber bundle diameter. 

Postprocedure Instructions

Patients are instructed to refrain from eating and drinking for at least 45 minutes subsequent to the application of the anesthetics so as to avoid aspiration. 

Coding Information and Supply Sources

ICD-9 Codes

Supplies

Nasolaryngoscopes may be ordered from the following suppliers: 
Additional supplies can be obtained as follows: 
  • Lidocaine hydrochloride (4% solution or 2% jelly) is available from Astra Pharmaceuticals, Westborough, MA (phone: 508-366-1100) or through a local pharmacy.

Oxymetazoline hydrochloride (0.05%) (Afrin spray) is produced by Schering-Plough, Kenilworth, NJ (phone: 908-298-4000) and is available through a local pharmacy. 

Bibliography

Bent J. Pediatric laryngotracheal obstruction: current perspectives on stridor. Laryngoscope .  2006;116(7):1059. [View Abstract]
Couch ME, Blaugrund J, Kunar D. History, physical examination and the preoperative evaluation. In: Cummings CW, Haughey BH, Thomas JR, et al., eds. Cummings Otolaryngology: Head and Neck Surgery (4th ed.). Philadephia: Elsevier Mosby;  2005:3–24.
Plant RL, Samlan RA. Visual documentation of the larynx. In: Cummings CW, Haughey BH, Thomas JR, et al., eds. Cummings Otolaryngology: Head and Neck Surgery (4th ed.). Philadephia: Elsevier Mosby;  2005:1989–2007.
Zarnitz P. Guidelines for performing fiberoptic flexible nasal endoscopy and nasopharyngolaryngoscopy on adults. ORL Head Neck Nurs .  2005;23(2):13–18. [View Abstract]
2008 MAG Mutual Healthcare Solutions, Inc.’s Physicians’ Fee and Coding Guide. Duluth, Georgia. MAG Mutual Healthcare Solutions, Inc. 2007.
 
×