It is a fibro muscular tube that lies behind: Nose. Mouth. Larynx. It extends from : Base of the skull To 6th cervical vertebra. It is Funnel shaped. It has: Upper expanded end that lies under the skull and A narrow lower end that becomes continuous with the Esophagus. Posterior: Prevertebral muscles and fascia. Lateral: (1) Auditory tube. (2) Styloid process and its muscles. (3) Carotid sheath and its contents. (4) Thyroid gland. It is deficient. It is replaced by: Posterior nasal openings. Oropharyngeal isthmus. Inlet of the larynx. 1. Mucosa : Continuous with that of the nose ,auditory tube, oral cavity , larynx and esophagus. 2. Fascia: Thickened Internally: Paryngobasilar fascia. Externally: Buccopharynge fascia. 3. Muscles : circular & longitudinal. CONSTRICTORS: Superior. Middle. Inferior. They propel the bolus of food down into the esophagus. They overlap like three glasses stacked one inside the other. Each one fans out from its anterior attachment and passes posteriorly around the pharynx. They join each other in the: Pharyngeal Raphe A fibrous midline raphe which extends from the occipital bone to the esophagus. It is the lowest fibers of the inferior constrictor muscle. Action : 1. A sphincter on the lower end of the pharynx. 2. Prevents the entry of air into the esophagus in between swallowing. Stylopharyngeus. Salpingopharyngeus. Palatopharyngeus. Origins : Styloid process . Pharyngotympanic tube. Soft palate. Insertion: To the pharyngeal wall. Action: 1. Elevate the larynx and pharynx. 2. Pull the pharynx forward during swallowing and speaking. (1) Between: Base of the skull and the superior constrictor : Pharyngobasilar fascia. Tensor palati. Levator palati. (2) Between: Superior and Middle constrictors: It is a triangular gape . It allows : A. muscles, vessels & nerves to pass between the tongue and regions lateral to pharynx. B. Stylopharyngeus tendon to slip into the pharynx. (3) Between: Middle & Inferior constrictors: Internal laryngeal nerve & superior laryngeal vessels. (4) Below: Inferior constrictor: The recurrent laryngeal nerve &inferior laryngeal vessels. LARYNGO PHARYNX NASO PHARYNX OROPHARYNX It has a respiratory function. It is Behind the posterior nasal openings (Choanae) AND Above the Soft palate. Roof: Basilar part of occipital bone. Body of sphenoid. It has A collection of lymphoid tissue (pharyngeal tonsil) in its submucosa. Floor : Sloping upper surface of the soft palate. Posterior wall: Anterior arch of atlas. Anterior : Choanae. It is a gap in the floor between the free end of the soft palate and the posterior wall. It is closed in swallowing by the elevation of the soft palate and pulling forward of the posterior wall. Lateral wall : 1. Pharyngeal opening of the auditory tube. 2.Tubal elevation: The elevated posterior margin of the tube. Pharyngeal Recess : It is a slit like depression on each side behind the tubal elevation. 3. Salpingo-pharyngeal fold of mucous membrane produced by the salpingopharyngeal muscle. 4.Tubal tonsil: It is a collection of lymphoid tissue behind the opening of the auditory tube. Hypertrophy and infection of the pharyngeal tonsils. It causes: obstruction of the posterior nasal openings. The patient: breathes through the mouth and snores loudly at night. It can cause: deafness and recurrent otitis media due to its close relation to the auditory tube. It is behind the mouth cavity. It extends from: Soft palate TO The upper border of the Epiglottis. Roof : It is the under surface of the soft palate and the pharyngeal isthmus. It has collection of lymphoid tissue. Floor : Posterior 1/3 of the tongue & the interval between the tongue and the anterior surface of the epiglottis. Lingual tonsil : A collection of lymphoid tissue on the posterior 1/3 of the tongue. Lateral wall : Palatoglossal arch A mucous fold overlying the palatoglossal muscle. It marks the boundary between the oral cavity and the oropharynx. The arched opening between the two folds is the Oropharyngeal isthmus. Palato-pharyngeal arch A mucous fold behind the palatoglossal arch. It overlies the palatopharyngeal muscle. Anterior : It opens into the mouth cavity through the oropharyngeal isthmus. Posterior wall : Body of 2nd cervical vertebra. The upper part of the body of the 3rd vertebra. Two oval bodies of lymphoid tissue. They have their maximum size in childhood. They lie on each side in the tonsilar sinus in the lateral wall of the oropharynx between the palatoglossal arches (anterior) and palatppharyngeal arches (posterior) They lie on the mucosa lining the Superior Constrictor muscle. The capsule is separated from the superior constrictor muscle by loose fascia. This fascia contains: The External palatine vein. The Facial artery is lateral to the muscle. The Internal carotid artery lies about 1’’ (2.5) cm behind and lateral to the tonsil. Superior: Soft palate. It is continuous with the lymphoid tissue on its undersurface . Inferior : Posterior third of tongue. It is continuous with the lingual tonsil. Arterial : Tonsillar arteries from : Facial. Ascending palatine. Venous Drainage: External palatine vein. Pharyngeal venous plexus. Pharyngeal and Facial veins. Juglodigastric nodes: Below and behind mandible. Glossopharyngeal nerve supplies its mucosa. The tonsils are a common site of infection. Sore throat , Pyrexia and Tender Enlarged juglodigastric lymph nodes. After tonsilectomy The external palatine vein may be the source of postoperative bleeding. It is a Peritonsilar abscess. It is due to the spread of infection from the palatine tonsil to the loose connective tissue outside the capsule. It extends from: The upper border of the epiglottis and pharyngoepiglottic fold TO The lower border of the cricoid cartilage(C6). Anterior : Inlet of the larynx. Posterior wall: Bodies of 3rd , 4th ,5th and 6th cervical vertebrae. Lateral wall: Thyroid cartilage. Thyrhyoid membrane. Pair of mucosal pouches anterior to the cavity of laryngopharynx. They are between: The base of the tongue AND The epiglottis. One on each side between the median and lateral glossoepiglottic folds. Pair of mucosal recesses. Between: medially The central part of the larynx from which it is separated by the aryepiglottic fold. laterally The thyroid cartilage and thyroyhyoid membrane. Function: It is an important channel that directs solids and liquids from the oral cavity around the raised laryngeal inlet into the esophagus. A foreign body in the fossa causes the patient to gag violently. Nerves related: Branches of internal & recurrent Laryngeal nerves lie deep to its mucous membrane. Nerve injury: They are liable to be injured when a foreign body ( bony fish) is lodged in the fossa. The following arteries supply the pharynx : 1. Ascending pharyngeal. 2. Ascending palatine. 3. Facial. 4. Maxillary. 5. Lingual. The pharynx is drained through the Pharyngeal venous plexus. The plexus drains: Superiorly: into the Pterygoid venous plexus. Inferiorly: into the facial and internal jugular veins. Most of the Motor and sensory supply of the pharynx is through nerves which form the pharyngeal plexus. Formed from: Pharyngeal branches of the Vagus. Branches from External laryngeal nerve (from superior laryngeal). Pharyngeal branches of Glossopharyngeal. Sympathetic fibers The only muscle of the pharynx which is innervated directly by a branch of the Glossopharyngeal nerve. Nasopharynx : pharyngeal branch of Maxillary nerve. Laryngopharynx: pharyngeal plexus (Vagus nerve). Oropharynx : pharyngeal plexus (Glossopharyngeal nerve). Direct to: Deep cervical nodes. Indirect to : Retropharyngeal. Paratracheal nodes. The lymphoid tissue of the pharynx is generally enlarged in childhood. 1. The palatine tonsils: a. Related to the superior constrictor of the pharynx. b. Borderd anteriorly by the palatoglossus muscle. c. Receives some of its blood supply from the facial artery. d. Lies in the oral cavity. e. The internal carotid artery is at its lateral side. 2. Each of the following is related to the walls of the laryngeal part of the pharynx EXCEPT: a. Piriform fossa. b. Cricoid cartilage. c. Thyrohyoid membrane. d. Thyroid cartilage. e. Palatine tonsil 3. The pharynx: a. Extends from the base of the skull to the 4th cervical vertebra. b. It is supported externally by the pharyngobasilar fascia. c. It is related posteriorly to the prevertebral fascia. d. It is related anteriorly to the pretracheal fascia. e. Its muscles have motor supply from the pharyngeal plexus 4. The inferior constrictor muscle of the pharynx has nerve supply from: a. Accessory nerve. b. Hypoglossal nerve. c. Internal laryngeal nerve. d. Pharyngeal plexus. e. Ansa cervicalis. 5. The piriform fossa is: a. Located above the pharyngeal tonsil. b. Located within the pharyngobasilar fascia. c. Located on each side of the larynx. d. Located posterior to the salpingopharyngeal fold. e. Related laterally to the cricoid cartilage. 6. Structures entering the pharynx between the superior and middle constrictor muscles are: a. Recurrent laryngeal nerve. b. Internal laryngeal nerve. c. Glossopharyngeal nerve. d. Superior laryngeal artery. e. Inferior laryngeal artery. 7. The middle constrictor muscle: a. Lies inner to the superior constrictor. b. Attached anteriorly to the pharyngeal raphe. c. The internal laryngeal nerve is between it and the inferior constrictor. d. The stylopharyngeus muscle passes between it and the superior constrictor. e. Propels the bolus of food down into the esophagus. 8. Palatine tonsil: a. Its lymph drainage is to the submandibular lymph nodes. b. Lies in the oral cavity. c. Lies on the middle constrictor. d. The palatopharyngeal arch is anterior to it. e. Its venous blood drain into the external palatine vein. 9. Interior of the pharynx: a. Receives a sensory innervation from the maxillary nerve. b. Has the palatine tonsil in the lateral wall. c. Has an anterior extension on each side of the larynx known as the vallecula. d. Has a ridge formed by the salpingopharyngeus muscle. e. The pharyngeal tonsil is a collection of lymphoid tissue on its roof. 10. The following arteries supply the pharynx EXCEPT: a. Ascending palatine. b. Sphenopalatine. c. Ascending pharyngeal. d. Lingual. e. Maxillary.