Lecture 19 - Pharynx and Larynx

Question 1

Pharynx

Answer 1

Extends between rami of the mandible and the base of the cranium Divisions: nasopharynx, oropharynx, hypopharynx •Muscles of mastication pass on either side of the pharynx in the infratemporal fossa from cranium to mandible. •Posteriorly the pharynx is in contact with the prevertebral fascia of the somatic neck.

Question 2

Nasopharynx

Answer 2

Opens into nasal cavity

Question 3

Oropharynx

Answer 3

Opens into oral cavity

Question 4

Hypopharynx

Answer 4

Continuation into larynx and esophagus •Nasal choanae mark beginning of nasal pharynx. •Floor is formed by soft palate. •Posteriorly and superiorly relations are the atlas and the basilar occipital bone. •Auditory tube opens on lateral wall of nasopharynx. •Cartilaginous wall of the tube creates the torus tubarius.

Question 5

Salpingopharyngeus muscle

Answer 5

Nasopharynx •Originates from end of auditory tube •Raises pharynx during swallowing •Covered by salpingopharyngeal fold

Question 6

Pharyngeal tonsils

Answer 6

Nasopharynx •AKA: adenoids •Embedded in posterior wall of nasopharynx •Regress by 8 years

Question 7

Faucial pillars

Answer 7

Oropharynx •Palatoglossus muscle •Palatopharyngeus muscle

Question 8

Tonsillar fossae

Answer 8

Oropharynx •Lie between diverging fauces •Contain palatine tonsils •Related to space between superior and middle pharyngeal constrictors •Represents the second pharyngeal pouch

Question 9

Tonsils

Answer 9

Arterial supply: •Tonsilar branches from: •Maxillary artery (branches of) •Facial artery (branches of) •Lingual artery (branches of) Waldeyer’s ring: •Ring of lymphoid tissue around pharynx; includes: •Pharyngeal tonsils •Palatine tonsils •Tubal tonsils •Lingual tonsils

Question 10

Pharyngeal Musculature

Answer 10

three overlapping constrictors and three diagonal muscles: •Meet posteriorly at pharyngeal raphe. •Overlap constrictor muscles above. •Lateral gaps occur between constrictor muscles anteriorly. •Used in swallowing

Question 11

Superior constrictor (pharyngeal)

Answer 11

•Lies deep to mandibular ramus in infratemporal fossa •Attached to pterygoid plate and mandibular and maxillary alveolar processes •Posteriorly attached to pharyngeal tubercle of occipital bone •Superior edge is free, creating a narrow space below the base of the cranium: •Provides passage for auditory tube

Question 12

Middle constrictor

Answer 12

•Arises anteriorly from stylohyoid ligament and horns of hyoid bone •Fibers pass posteriorly to pharyngeal raphe •Separated from superior constrictor by a gap: •Provides passage for stylopharyngeus muscle, pharyngeal branch of CN IX, and tonsillar branch of facial artery

Question 13

Inferior constrictor

Answer 13

•Fans out superiorly but becomes more tubular inferiorly •Fibers insert posteriorly on pharyngeal raphe •Cricopharyngeus portion of muscle functions as a sphincter at superior end of esophagus

Question 14

Gap above superior pharyngeal constrictor

Answer 14

•Closed by pharyngobasilar fascia •Traversed by auditory tube •Forms tonsillar bed

Question 15

Gap above middle constrictor

Answer 15

Traversed by: •Stylopharyngeus muscle •Glossopharyngeal nerve

Question 16

Palatopharyngeus muscle:

Answer 16

•Underlies posterior faucial pillar (palatopharyngeal fold) •Arises from palate and inserts on pharyngeal musculature •Functions as sphincter between oral cavity and pharynx •Helps raise larynx during swallowing •Innervated by CN X

Question 17

Salpingopharyngeus muscle:

Answer 17

•Lies under salpingopharyngeus fold •Originates from torus tubarius •Inserts onto midpharynx musculature •Raises pharynx and larynx during swallowing •Innervated by CN X

Question 18

Stylopharyngeus muscle:

Answer 18

•Originates from styloid process •Passes through hiatus between superior and middle constrictors •Inserts onto pharyngeal musculature and thyroid cartilage •Raises pharynx during swallowing •Innervated by CN IX

Question 19

Glossopharyngeal nerve (IX):

Answer 19

•Nerve of third arch •Exits skull via jugular foramen •Winds around stylopharyngeus muscle and enters pharynx through gap between superior and middle pharyngeal constrictors •Supplies stylopharyngeus muscle

Question 20

Vagus nerve (X):

Answer 20

•Nerve of fourth (through sixth) arch •Supplies all pharyngeal musculature except stylopharyngeus muscle

Question 21

Innervation and Blood Supply of Pharynx

Answer 21

Innervation: •Vagus nerve via pharyngeal plexus: •Except stylopharyngeus (CN IX) •Recurrent laryngeal nerves branches of vagus nerve) to lower part of inferior constrictor Blood supply: •Ascending pharyngeal artery

Question 22

Larynx

Answer 22

formed by a rigid framework of bones, cartilage, and ligaments: Unpaired symmetrical structures: •Hyoid bone •Thyroid cartilage •Cricoid cartilage •Epiglottis •Paired cartilages: •Arytenoid •Corniculate •Cuneiform Function: •Compound sphinctor: •Closes airway during swallowing and Valsalva’s maneuver •Constricts airway for phonation

Question 23

Hyoid

Answer 23

“U”-shaped bone: •Median body •Greater cornua(horns) •Superior cornua Attachment site for numerous muscles

Question 24

Epiglottis

Answer 24

Spoon-shaped structure that extends posteriorly and superiorly into the hypopharynx. attached to hyoid and thyroid cartilage. 2 folds and vallecular recesses Anterior surface is attached to the hyoid: •Hyoepiglottic ligament Attached to the thyroid cartilage: •Thyroepiglotticligament

Question 25

Piriform Recess

Answer 25

Part of laryngopharynx lateral to larynx. Lateral boundary: •Thyrohyoid membrane and thyroid cartilage Medial boundary: Aryepiglottic fold; arytenoid and cricoid cartilages. •Site of lodgement

Question 26

Laryngeal Cavity and Folds

Answer 26

Characterized by superior and inferior pairs of folds

Question 27

Vestibule

Answer 27

lies between vestibular folds

Question 28

vestibular folds

Answer 28

false vocal cords rima vestibuli (space btwn vestibular folds)

Question 29

Ventricular folds

Answer 29

true vocal cords vocal ligaments

Question 30

rima glottidis

Answer 30

space btwn vocal folds narrowest part of laryngeal cavity opens and closes to regulate the passage of air

Question 31

infraglottic cavity

Answer 31

lies btwn ventricular folds and lower border of cricoid cartilage continuos inferiorly with trachea

Question 32

Superior laryngeal artery:

Answer 32

From superior thyroid artery

Question 33

Inferior laryngeal artery:

Answer 33

Branch of inferior thyroid artery

Question 34

Piriform fossae

Answer 34

Inferior to lateral glossoepiglottic folds

Question 35

Innervation of the epiglottis

Answer 35

Glossopharyngeal nerve: •Sensation from upper epiglottic surface Superior laryngeal nerve (CN X): •Taste buds of epiglottis •Sensation from lower epiglottis surface and supraglottic larynx (cough reflex)

Question 36

Folds of the epiglottis

Answer 36

•Median glossoepiglottic fold •Paired lateral glossoepiglottic folds

Question 37

Vallecular recesses (epiglottis)

Answer 37

•Located on either side of the median glossoepiglottic fold •Common sites for lodgement

Question 38

Thyroid

Answer 38

Question 39

Arytenoids

Answer 39