Larynx
Anatomy
The Larynx, also known as the voice box, is an organ in the top of the neck involved in breathing, producing sound and protecting the trachea against food aspiration. It manipulates pitch and volume, which is essential for phonation. The larynx houses the vocal cords, and manipulates pitch and volume, which is essential for phonation. It is situated just below where the tract of the pharynx splits into the trachea and the esophagus.
Structure
The larynx extends vertically from the tip of the epiglottis to the inferior border of the cricoid cartilage. Its interior can be divided into three sections: the vestibule, the ventricle and the infraglottic cavity. The vestibule is the section of the laryngeal cavity from the laryngeal entrance to the vestibular folds. The ventricle is a small sinus between the vestibular and vocal folds. The infraglottic cavity extends from the vocal folds to the inferior border of the cricoid cartilage.
Function
The larynx performs several functions in humans, its most immediate is the routing of air and food into the proper channels. The larynx also plays a crucial role in the effective production of speech, as it houses the vocal cords, and manipulates pitch and volume. The strength of expiration from the lungs also contributes to the volume of sound produced. Additionally, the larynx functions in the protection of the trachea from food aspiration, which is done by the closure of the larynx at the epiglottis.
Clinical significance
Various diseases, including laryngitis, laryngeal cancer, and laryngeal papillomatosis, can affect the larynx. Laryngitis is an inflammation of the larynx. It causes hoarse voice or temporary complete loss of the voice because of irritation to the vocal folds (vocal cords). Laryngeal cancer, also known as cancer of the larynx or laryngeal carcinoma, are mostly squamous cell carcinomas, reflecting their origin from the skin of the larynx. Laryngeal papillomatosis, also known as recurrent respiratory papillomatosis or glottal papillomatosis, involves the growth of small, wart-like tumors in the larynx due to the human papillomavirus (HPV).