Internal laryngeal nerve

The internal laryngeal nerve is one of the two branches of the superior laryngeal nerve and provides sensory innervation of the laryngeal mucosa down to the level of the vocal cords (supraglottic larynx).

Summary

• origin: arises as the larger of the two branches of the superior laryngeal nerve at the level of the greater cornu of the hyoid bone
• course
  • descends anterior to the thyrohyoid membrane piercing it at the level of the vallecula before dividing into 2 branches
• branches and supply
  • upper branch: runs horizontally
    • sensory and secretomotor supply to the mucosa of the pharynx, laryngeal vestibules, epi­glottis and valleculae
  • lower branch: runs vertically, downwards in the medial wall of the piriform recess
    • sensory and secretomotor supply to the aryepiglottic fold, the mucosa on the back of the arytenoid cartilage and part of the transverse arytenoid muscle
    • unites with an ascending branch of the recurrent laryngeal nerve after piercing the inferior pharyngeal constrictor muscle

Related pathology

Compression of the internal laryngeal nerve by an enlarged triticeal cartilage may cause dysphagia, odynophagia and sensation of a foreign body.