As a preface it should be mentioned that Sebileau* accurately described the general area of the larynx and hypopharynx as the crossroads of the air and food passages ("carrefour aero-digestif"). This concept is particularly applicable to the pyriform sinuses, which are in a preeminent position to refer symptoms to both structures. A wide variety of diseases, offering interesting diagnostic and therapeutic problems, may originate in this portion of the hypopharynx, which may be approached by both peroral and external surgical procedures.
Anatomically the hypopharynx is that portion of the pharynx extending from the hyoid bone to the lower border of the cricoid cartilage. The aperture of the larynx communicates with it, and the inferior constrictor muscles (thyropharyngeus and cricopharyngeus) provide muscular support and coordinated action. The pyriform sinus is that portion on each side of the laryngeal orifice bounded laterally by the ala of the thyroid cartilage and thyrohyoid membrane