Hypopharynx anatomy

The pharynx is a 13 cm long fibro-muscular tube that extends from the base of the skull to the 6th cervical vertebra. It is divided into 3 parts: the nasopharynx, oropharynx, and laryngopharynx. The hypopharynx extends from the level of the hyoid bone above to the lower border of the cricoid cartilage below. It has three subdivisions: the pyriform sinus, post cricoid region, and posterior pharyngeal wall. The pyriform sinus lies on either side of the larynx and drains into cervical lymph nodes.