Pharynx

Question 1

Describe the pharynx:

Answer 1

Musculomembranous tube located posterior to nasal and oral cavities and larynx

Extends from the base of skull to level of C6

Continuous with the oral and nasal cavities, superiorly

Continuous with larynx and oesophagus inferiorly

Divided into 3 parts - oropharynx, nasopharynx and laryngopharynx

Question 2

What are the choanae ?

Answer 2

Opening at the back of the nasal cavity

Boundaries;
- anteriorly and inferiorly by palatine
- superiorly and posteriorly by sphenoid
- laterally by medial pterygoid plates
- medially by vomer

Question 3

What are the fauces ?

Answer 3

The opening at the back of the oral cavity into pharynx

Boundaries;
- superiorly by the soft palate
- laterally by the palatoglossal and palatopharyngeal arches
- inferiorly by the tongue

Arches;
- form pillars of fauces
- anterior pillar formed by palatoglossus
- posterior pillar formed by palatopharyngeus muscles
- Tonsillar fossa which is the location of the palatine tonsil

Question 4

What are the circular muscles of the larynx and their attachments ?

Answer 4

Superior constrictor
- anterior attach = Medial pterygoid , plate , Pterygomandibular ligament, Mandible, Side of tongue
- posterior attach = Pharyngeal tubercle and Median pharyngeal raphe

Middler constrictor
- anterior is hyoid bone
- posterior is median pharyngeal raphe

Inferior constrictor;
- anterior is thyroid and cricoid cartilage
- posterior is median pharyngeal raphe

Question 5

What is the function and nervous innervation of circular muscles of larynx

Answer 5

Vagus nerve (cranial nerve X)

Propel bolus of food inferiorly

Question 6

What are the longitudinal muscles of the pharynx and their attachments innervation and function ?

Answer 6

Stylopharyngeus
- origin is styloid process
- insertion is soft tissue pharynx
- glossopharyngeal (IX)
- elevate pharynx during swallowing

Palatopharyngeus;
- origin is soft palate
- insertion is soft tissues of pharynx
- vagus (X)
- elevate pharynx during swallowing

Salpinopharyngeus;
- origin is eustachian tube
- insertion is soft tissues of pharynx
- vagus (X)
- elevate pharynx and open eustachian tube during swallowing

Question 7

Describe the boundaries and contents of the oropharynx:

Answer 7

Boundaries;
- uvula superiorly
- oral cavity/ fauces anteriorly
- faucial arches laterally
- base of tongue + epiglottis inferiorly

Contents:
- posterior 1/3 of tongue
- palatine tonsils
- lingual tonsils

Question 8

Describe the boundaries and contents of the nasopharynx:

Answer 8

Boundaries;
- anteriorly nasal cavity/ conchae
- superiorly sphenoid and occipital bone
- inferiorly uvula

Contents;
- tubal tonsils
- pharyngeal tonsils
- opening of eustachians

Question 9

Describe the laryngeal inlet;

Answer 9

In laryngopharynx, the larynx
lies anteriorly and is slightly invaginated

Creates;
- piriform fossae laterally
- vallecula anteriorly

Question 10

What are the boundaries and contents of the laryngopharynx ?

Answer 10

Boundaries;
- oropharynx superiorly
- laryngeal inlet anteriorly
- faucial arches laterally
- cricoid inferiorly

Contents;
- Posterior ⅓ of tongue
- Palatine tonsils
- Lingual tonsils

Question 11

Describe the Torus tubaris:

Answer 11

Tubal elevation to guard auditory opening

Lymphoid tissue overlies tubal elevation - tubal tonsil

Salpingopharyngeal fold

Salpingopalatine fold

Pharyngeal recess

Question 12

Describe the process of swallowing:

Answer 12

Tongue moves bolus to posterior oral cavity

Aim to get bolus into pharynx not larynx

Tongue pushes against hard palate and bolus towards soft palate

Closes off nasopharyngeal from oropharynx

Hyoid bone raised due to digastric and stylohyoid muscles

The larynx raises, and causes the epiglottis to close over

As the bolus enters pharynx, the constrictors contract