Infraglottic cavity

The infraglottic cavity is the portion of the larynx situated inferior to the glottis.  It is situated between the vocal cords (superior limit), and the inferior border of the cricoid cartilage (inferior limit) where it is continuous with the trachea. 

On transverse section, the infraglottic cavity appears elliptical in shape superiorly, and circular in shape inferiorly. It is wider inferiorly. The walls of the infraglottic cavity are lined with respiratory epithelium. Structural support is provided by the cricothyroid ligament above, and the cricoid cartilage below.