Mirror laryngoscopy is typically done to evaluate symptoms in the pharynx and larynx.
(See also Evaluation of the Patient with Nasal and Pharyngeal Symptoms and Overview of Laryngeal Disorders.)
Indications
Laryngoscopy may be indicated to evaluate
In particular, patients at high risk of head and neck cancer (eg, heavy smokers or alcohol users) may benefit from laryngoscopy, especially if they have had hoarseness, sore throat, or ear pain for > 2 weeks.
Laryngoscopy also may be useful to evaluate the airway prior to orotracheal intubation.
Contraindications
Absolute contraindications
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Suspected epiglottitis
In such cases, stimulation of the laryngopharynx may further compromise the airway. If laryngoscopy is essential, it should be done in the controlled setting of an operating room with a person skilled at difficult airway management (including surgical techniques) present.
Relative contraindications
Complications
Equipment
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Curved dental mirror
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Antifogging solution, warm water (about body temperature), or alcohol swab
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Headlamp or other external light source that can be used hands-free if possible
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Gloves
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Protective eyewear
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Gauze pad 10 cm × 10 cm (4 in × 4 in)
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Tongue depressor
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Topical anesthetic spray (eg, lidocaine, benzocaine)
Additional Considerations
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Most patients tolerate mirror laryngoscopy without anesthesia of the oropharynx; however, topical anesthesia may be needed.
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If the patient does not tolerate this procedure, flexible laryngoscopy should be done.
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Mirror laryngoscopy provides only a limited view of the subglottic larynx and proximal trachea. If pathology is suspected in these regions, use another procedure, such as bronchoscopy.
Relevant Anatomy
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The pharynx includes the nasopharynx, oropharynx, and hypopharynx.
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The larynx connects the pharynx to the trachea and is suspended from the hyoid bone. It includes 3 single and 3 paired cartilage structures: single (epiglottis, thyroid, and cricoid) and paired (arytenoid, cuneiform, and corniculate). The larynx extends from the tip of the epiglottis down to the inferior aspect of the cricoid cartilage and includes the vocal folds.
Positioning
Step-by-Step Description of Procedure
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Adjust the external light source.
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Warm the mirror with warm water (about body temperature) to prevent fogging (check to make sure mirror is not too hot). Alternatively, coat the mirror with antifogging solution or alcohol.
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Wrap the patient's tongue with gauze and grasp it with your nondominant hand. The gauze will prevent the tongue from slipping and protect it from injury by the lower incisor teeth.
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Gently pull on the tongue.
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Instruct the patient to breathe deeply through the mouth, to help prevent gagging.
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Slide the mirror into the oropharynx without touching the tongue or any mucosa.
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Place the back of the mirror against the uvula and gently insert it further until the larynx can be clearly seen.
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If gagging occurs, remove the mirror and spray the posterior oropharynx with a topical anesthetic.
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Move the mirror gently and as little as possible to inspect the base of the tongue, valleculae, epiglottis, piriform sinuses, arytenoids, false and true vocal cords, and if possible the larynx below the vocal cords.
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Rotate the mirror from side to side with thumb and forefinger to bring lateral structures into view.
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Fully inspect the vocal cords. Instruct the patient to say "eeee," which will contract the vocal cords, and assess their function.
Aftercare
Warnings and Common Errors
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Failure to align the light source as closely as possible with line of sight
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Failure to warm the mirror, because a cold mirror will fog
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Failure to maintain hold of the patient's tongue to keep it retracted
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Allowing the patient to lean back, which will prevent full visualization
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Having the mirror at the wrong angle to see the larynx
