Lec2 Pharynx Anatomy PDF

1 DR/ABDELHAMID 2 DR/ABDELHAMID ILOS 1-By the end of this lecture, the student should be able to describe the pharynx as regards: 1-Site&extent. 2-Strtucture. 3-Divisions&functions. 4-Interior. 5-Supply(arterial&nerve). 6-Clinical points. 3 DR/ABDELHAMID PHARYNX NOSE MOUTH LARYNX C6 4 DR/ABDELHAMID...

1 DR/ABDELHAMID 2 DR/ABDELHAMID ILOS 1-By the end of this lecture, the student should be able to describe the pharynx as regards: 1-Site&extent. 2-Strtucture. 3-Divisions&functions. 4-Interior. 5-Supply(arterial&nerve). 6-Clinical points. 3 DR/ABDELHAMID PHARYNX NOSE MOUTH LARYNX C6 4 DR/ABDELHAMID Pharynx 1. Definition: The pharynx is a musculofascial half-cylinder tube that links the oral and nasal cavities in the head to the larynx and esophagus in the neck 2.Functions:  The pharyngeal cavity is a common pathway for air and 'food'.  Defense functions (Lingual, pharyngeal, and palatine tonsils are on the deep surface of the pharyngeal walls). 5 DR/ABDELHAMID Pharynx Site & extent: The pharynx is attached above to the base of the skull and is continuous below the esophagus at the level of vertebra C6 The walls of the pharynx are attached anteriorly to the posterior margins of the nasal cavities, oral cavity, and larynx. Based on these anterior relationships the pharynx is subdivided into three regions, the nasopharynx, oropharynx, and laryngopharynx 2.Communications: the posterior apertures (choanae) of the nasal cavities open into the nasopharynx; the posterior opening of the oral cavity (oropharyngeal isthmus) opens into the oropharynx; the superior aperture of the larynx (laryngeal inlet) opens into the laryngopharynx. 6 The pharyngotympanic tubes open into the lateral walls of the nasopharynx conducting air to middle ear cavity. DR/ABDELHAMID Features present in the mucosal surface of the interior of Pharynx Nasopharynx: 1-The pharyngeal tonsil: is a large collection of lymphoid tissue in the mucosa covering the roof of the nasopharynx. Enlargement of this tonsil, known as adenoids, can occlude the nasopharynx so that breathing is only possible through the oral cavity. 2-The opening of the pharyngotympanic tube Oropharynx: 1-Palatine tonsils Laryngopharynx: 1-Piriform fossa 7 DR/ABDELHAMID Sup. Constrictor Mid. Constrictor Inf. Constrictor 8 Muscles of pharynx wall DR/ABDELHAMID Pharyngeal tonsil Auditory tube 9 DR/ABDELHAMID Interior of nasopharynx Pharyngo tympanic tube 10 DR/ABDELHAMID Interior of oropharynx Palatine tonsils 11 DR/ABDELHAMID Palatine tonsils 12 DR/ABDELHAMID Interior of laryngopharynx 13 DR/ABDELHAMID Arterial blood supply of pharynx Supplied by many pharyngeal&palatine branches from the external carotid artery 14 DR/ABDELHAMID ARTERIAL BLOOD SUPPLY 15 DR/ABDELHAMID NERVE SUPPLY 16 DR/ABDELHAMID Nerve supply of pharynx: Motor and most sensory innervation (except for the nasopharynx) is mainly through branches of the vagus [X] and glossopharyngeal [IX] nerves. 17 DR/ABDELHAMID 18 DR/ABDELHAMID