The pharynx Flashcards
State the location, relations and extents of the pharynx
Length: 5 inches
Location: in front of upper 6 cervical vertebrae
Extent: from base of skull to C6( lower border of the cricoid cartilage to continue as the esophagus)
Relations
1. Anterior: nasal cavity, oral cavity and larynx.
2. Posterior: upper 6 cervical vertebrae
3. Sides:
a. Styloid process and structures attached to it; stylopharyngeus, styloglossus, stylohyoid muscles and stylomandibular and stylohyoid ligaments
b. Vessels: carotid arteries ( ECA, CCA & ICA) and internal jugular vein.
c. Nerves:- last 4 cranial nerves and sympathetic chain
Name the parts of the pharynx.
- Nasopharynx- behind the nasal cavities
- Oropharynx - behind the oral cavity
- Laryngopharynx- behind the larynx
Discuss the boundaries and features of the nasopharynx
Boundaries:
1. Roof & posterior wall- adenoid (pharyngeal tonsil)
2. Floor- soft palate
3. Anterior - posterior nasal orifice
4. Lateral wall: contains
- opening of auditory tube/ eustatian tube
- tubal elevation
- salpingopharyngeal fold- formed by salpingopharyngeal muscle
- pharyngeal recess
Name the features of the oropharynx
- Palatine tonsil- in tonsillar fossa
- Anterior - palatoglossal arch
- Posterior - palatopharyngeal arch
Discuss the location and boundaries of the palatine tonsil.
Site: tonsillar fossa bounded by:
1. Anterior: palatoglossal arch
2. Posterior: palatopharyngeal arch
3. Floor: superior constrictor muscle
State the blood supply of the palatine tonsils
- Facial artery: tonsillar branch- main supply
- Facial artery: ascending palatine branch
- Ascending pharyngeal: from ECA
- Lingual artery: through dorsal lingual artery
- Lesser palatine: from greater palatine artery
State the features of the laryngopharynx and their boundaries.
- Laryngeal inlet: bounded by
- anterior: epiglottis
_ posterior: arytenoid cartilage and interarytenoid fold. - sides: aryepiglottic fold
- anterior: epiglottis
- Pyriform fossa: lateral to aryepiglottic fold.
Name the layers of the pharyngeal wall.
- Buccopharyngeal fascia - loose areolar sheath
- Muscle layer
- Pharyngobasilar fascia- pharyngeal aponeurosis
- Mucous membrane
Name the muscles of the pharynx
Constrictor
1. Superior constrictor
2. Middle constrictor
3. Inferior constrictor
Longitudinal
1. Stylopharyngeus
2. Palatopharyngeus
3. Salpingopharyngeus
State the origins, insertions and actions of the three constrictor muscles
- Superior constrictor
• pterygoid hamulus
• pterygomandibular ligament
• mylohyoid line of mandible - Middle constrictor:
• stylohyoid ligament
• hyoid bone - Inferior constrictor:
• thyroid cartilage
• cricoid cartilage
• arch over cricothyroid muscles
Insertion:
• all insert to median raphe extending from the pharyngeal tubercle to the cricoid cartilage
State the origins, insertion and action of the three longitudinal muscles.
Origins
3. Salpingopharyngeus- from the eustachian (auditory) tube
2. Palatopharyngeus - from the palatine aponeurosis
1. Stylopharyngeus - from the styloid process.
Insertion
Posterior border of the lamina of the thyroid cartilage.
** Action**
Elevation of pharynx and larynx during swallowing.
Discuss the gaps in the lateral wall and state their contents
- Above the superior constrictor*
• auditory tube: cartilaginous part
• 2 muscles: tensor and levator palati.
• 2 arteries: ascending palatine & pharyngeal branch of ascending pharyngeal artery
- Above the superior constrictor*
- Between Superior and middle constrictors*
• glossopharyngeal nerve
• stylohyoid muscles
• stylohyoid ligament
- Between Superior and middle constrictors*
- Between the middle and inferior constrictors*
-Thyroid membrane which is pierced by:
• internal laryngeal nerve
• superior laryngeal artery
- Between the middle and inferior constrictors*
-
Below the inferior constrictor
• recurrent laryngeal nerve
• inferior laryngeal artery
State the arterial supply of the pharynx
1. 2 pharyngeal arteries
• ascending pharyngeal artery- from ECA
• pharyngeal branch - from maxillary artery
2. 2 from facial artery:
• tonsillar artery
• ascending Palatine artery
3.2 Palatine arteries: from maxillary
• greater palatine
• lesser palatine
4.2 dorsal lingual arteries: from lingual artery
State the Venous drainage of the pharynx
• Largely drained into pharyngeal Venous plexus located on the posterolateral aspect of the pharynx over the middle constrictor.
• drains into IJV
State the motor, sensory and sympathetic nerve supply of the pharynx.
motor
- all the muscles are supplied by the pharyngeal branch of the vagus( from the cranial root of accessory nerve) except the stylopharyngeus by the glossopharyngeal
Sensory:
1. Nasopharynx: maxillary
• pharyngeal branch of the pterygopalatine ganglion
2. Oropharynx: glossopharyngeal
• pharyngeal branch of IX nerve
3. Laryngopharynx: vagus
• internal laryngeal nerve of vagus
Sympathetic
Superior cervical sympathetic ganglion through pharyngeal plexus