A 23-year-old man comes to the emergency department due to a sensation of food being stuck in his throat. His symptoms started 2 hours ago after eating fish at a local seafood restaurant. He has tried swallowing multiple times to clear the food with no relief. The patient has no difficulty with breathing. He does not appear to be in significant distress on physical examination. Laryngoscopy reveals a fish bone lodged in the left piriform recess. During retrieval of the fish bone, a nerve is injured deep to the mucosa overlying the recess. Which of the following is most likely to be impaired in this patient?

Question

A 23-year-old man comes to the emergency department due to a sensation of food being stuck in his throat.  His symptoms started 2 hours ago after eating fish at a local seafood restaurant.  He has tried swallowing multiple times to clear the food with no relief.  The patient has no difficulty with breathing.  He does not appear to be in significant distress on physical examination.  Laryngoscopy reveals a fish bone lodged in the left piriform recess.  During retrieval of the fish bone, a nerve is injured deep to the mucosa overlying the recess.  Which of the following is most likely to be impaired in this patient?

Quizplus · Accepted Answer

11ec160b_356b_5351_9249_8bf00ebad34e_MD0001_00 The piriform recesses are small cavities that lie on either side of the laryngeal orifice. They are bounded medially by the aryepiglottic folds and laterally by the thyroid cartilage and thyrohyoid membrane. During normal swallowing, food is diverted by the epiglottis laterally through the piriform recesses into the esophagus without endangering the airway. A thin layer of mucosa overlying the piriform recess is all that protects the superficially coursing internal laryngeal nerve, a branch of the superior laryngeal nerve (part of the vagus nerve [CN X]). Unlike the recurrent and external laryngeal nerves that carry motor fibers to the muscles involved in vocal cord function, the internal laryngeal nerve contains only sensory and autonomic fibers. It mediates the afferent limb of the cough reflex by carrying sensation from the mucosa superior to the vocal cords. Damage to the internal laryngeal nerve can occur when foreign bodies (eg, chicken or fish bones) become lodged in the piriform recess or during attempts to retrieve them. The resulting reduction in laryngeal sensation can impair the cough reflex. (Choice B) The afferent limb of the gag reflex is mediated predominantly by the glossopharyngeal nerve (CN IX), whereas the efferent limb is carried by the vagus nerve (CN X). Although the internal laryngeal nerve is a branch of CN X, it does not carry motor fibers and is not involved in the gag reflex. (Choice C) The muscles of mastication are innervated by the mandibular branch of the trigeminal nerve (CN V₃). This nerve is involved in the jaw jerk reflex, which is typically prominent only in patients with upper motor neuron lesions. (Choice D) Salivation is mediated by the glossopharyngeal nerve (which innervates the parotid gland via the otic ganglion) and the facial nerve (which innervates submandibular and sublingual glands via the submandibular ganglion). These nerves do not lie in close proximity to the piriform recess. (Choice E) Although the internal laryngeal nerve carries taste sensation from the root of the tongue and epiglottis, its role in the perception of taste is extremely minor. Taste sensation is primarily mediated by glossopharyngeal nerve (posterior one-third of the tongue and oropharynx) and facial nerve (anterior two-thirds of the tongue). Educational objective: The internal laryngeal nerve mediates the afferent limb of the cough reflex above the vocal cords. Foreign bodies (eg, fish bones) can become lodged in the piriform recess and may cause damage to the nerve, impairing the cough reflex.

A 23-Year-Old Man Comes to the Emergency Department Due to a Sensation