Epiglottis

From Wikipedia, the free encyclopedia.

Epiglottis =
Laryngoscopic view of interior of larynx
Gray's subject #236 1095
Precursor 4th and 6th branchial arch[1]

The epiglottis is a flap of elastic cartilage tissue covered with a mucous membrane, attached to the root of the tongue. It projects obliquely upwards behind the tongue and the hyoid bone. It is often incorrectly used to refer to the uvula[1]

Contents

[edit] Anatomy and function

The epiglottis guards the entrance of the glottis, the opening between the vocal folds.

It is normally pointed upward, but during swallowing, elevation of the hyoid bone draws the larynx upward; as a result, the epiglottis folds down to a more horizontal position. In this manner it prevents food from going into the trachea and instead directs it to the esophagus, which is more posterior.

The epiglottis is one of nine cartilaginous structures that make up the larynx (voice box).

[edit] Clinical significance

[edit] Reflexes

The glossopharyngeal nerve (CN IX) sends fibers to the upper epiglottis that contribute to the afferent limb of the gag reflex. The superior laryngeal branch of the vagus nerve (CN X) sends fibers to the lower epiglottis that contribute to the afferent limb of the cough reflex. [2]

[edit] Infection of the epiglottis

In children, the epiglottis will occasionally become infected with Haemophilus influenzae or Streptococci in the trachea, causing massive inflammation. This condition has become rare in countries where vaccination against Haemophilus influenzae (Hib) is administered.

[edit] Additional images

[edit] Reference sites

  1. ^ hednk-025dEmbryology at UNC
  2. ^ April, Ernest. Clinical Anatomy, 3rd ed. Lippincott, Williams, and Wilkins.

[edit] External links

--24.24.213.211 (talk) 01:33, 30 October 2008 (UTC)

This is an extract from Wikipedia, the Free Encyclopedia
offerte voli | hoteles | precios | voli | die verzeichnis | annuarie web | stop smoking london