Pharynx Week 5 FINISHED

Question 1

What is the pharynx and where is it located?

Answer 1

Part of the digestive system posterior to the nasal cavities, oral cavity and larynx. It also has respiratory function

Question 2

Where does the pharynx extend? What does it lie against posteriorly?

Answer 2

Extends from the base of the skull to the inferior border of the cricoid cartilage (anteriorly) and the inferior border of C6 posteriorly
Posteriorly it lies against the prevertebral layer of the deep cervical fascia

Question 3

What is the widest point of the pharynx and where is it?

Answer 3

The widest point ~ 5cm opposite the hyoid bone

Question 4

What is the narrowest part of the pharynx and where is it?

Answer 4

Narrowest part ~1.5 cm at the inferior end of the pharynx where it is continuous with the oesophagus

Question 5

What are the 3 regions of the pharynx?

Answer 5

nasopharynx - posterior to the nasal cavity and superior to the soft palate

oropharynx - posterior to the mouth and the oral cavity

laryngopharynx - posterior to the larynx

Question 6

What is the nasopharynx and what is the function of the nasopharynx?

Answer 6

Respiratory function

Posterior extension of the nasal cavities

Question 7

What are the 2 openings from the nasal cavity into the nasopharynx?

Answer 7

The nasal cavities open into the nasopharynx via the 2 choanae (paired openings)

Question 8

What do the roof and the posterior surface of the nasopharynx form?

Answer 8

Roof and the posterior wall form a continuous surface that lie inferior to the body of the sphenoid and the basilar part of the occiput

Question 9

What are the pharyngeal tonsils also known as?

Answer 9

Adenoids

Question 10

Where are the pharyngeal tonsils/adenoids found?

Answer 10

Found in the roof and walls of the nasopharynx

Question 11

Where are the tubal tonsils found?

Answer 11

Lymphoid tissue near the pharyngeal orifice of the pharyngotympanic tube

Question 12

What is the function of the oropharynx?

Answer 12

Digestive function

Question 13

What is superior to the oropharynx?

Answer 13

The soft palate

Question 14

What is inferior to the oropharynx?

Answer 14

Base of the tongue and epiglottis

Question 15

What is lateral to the oropharynx?

Answer 15

Laterally palatoglossal and palatopharyngeal arches

Question 16

What are the palatine tonsils?

Answer 16

Lymphoid tissue found either side of the oropharynx

Question 17

What is the laringopharynx and where is it found?

Answer 17

Hypopharynx

• Found between the superior border of the epiglottis
• To the inferior border of the cricoid cartilage where it becomes continuous with the oesophagus
• Posteriorly find the bodies of C4-6 vertebrae

Question 18

What forms the laryngopharynx laterally and posteriorly?

Answer 18

Posteriorly and laterally formed by the middle and inferior constrictor muscles

Question 19

What forms the internal surface of the laryngopharynx?

Answer 19

Internally the wall is formed by the palatopharyngeus and stylopharyngeus muscles

Question 20

How does the laryngopharynx communicate with the larynx?

Answer 20

Communicates with the larynx via the laryngeal inlet

Question 21

How many layers of muscle are in the wall of the pharynx?

Answer 21

2 layers

Question 22

What is the orientation of the layers of muscle in the pharynx?

Answer 22

Externally circular

Internally longitudinal

Question 23

How does the muscle orientation in the pharynx differ from other organs?

Answer 23

The pharynx has a muscle orientation external circular and internal longitudinal which is opposite to that of other organs e.g. the bladder

Question 24

How many external constrictor muscles does the pharynx have? Are they voluntary or involuntary?

Answer 24

3

Involuntary

Question 25

Describe the constrictor muscles in the pharynx. Where do they insert posteriorly?

Answer 25

3 curved sheets which lie on the posterior wall and sides of the pharynx. Posteriorly they insert into the median fibrous raphe

Question 26

Where do the constrictor muscles of the pharynx descend from and where do they go to?

Answer 26

They descends from the pharyngeal tubercle on the base of the skull to blend in with the oesophagus

Question 27

What is the function of the pharyngeal muscles?

Answer 27

Contract sequentially superior to inferior | Propels food into the oesophagus

Question 28

What is the nerve supply to the pharyngeal muscles?

Answer 28

Nerve supply: - Pharyngeus plexus (Lies lateral wall of the pharynx mainly on the middle constrictor) - IX & X and sympathetic from the superior cervical ganglion

Question 29

Superior constrictor OIAN

Answer 29

``` Origin: Pterygoid hamulus (projection of the medial pterygoid plate) Pterygomandibular raphe (raphe = seam) (strand of tendinous fibres from the pterygoid hamulus to the posterior end of the mylohyoid line) ``` Insertion: Median raphe of pharynx, pharyngeal tubercle on the basilar part of the occipital bone Innervation: Pharyngeal branch of vagus and pharyngeal plexus Action: Constricts the wall of the pharynx during swallowing

Question 30

Middle constrictor OIAN

Answer 30

Origin: Stylohyoid ligament, horns of the hyoid bone Insertion: Median raphe of pharynx Innervation: Pharyngeal branch of vagus, pharyngeal plexus & branches of external & recurrent laryngeal nerves Action: Constricts the wall of the pharynx during swallowing

Question 31

Inferior constrictor OIAN

Answer 31

Origin: Oblique line of the thyroid cartilage, side of the cricoid cartilage Insertion: Median raphe of pharynx Innervation: Pharyngeal branch of vagus, pharyngeal plexus & branches of external & recurrent laryngeal nerves Action: Constricts the wall of the pharynx during swallowing

Question 32

What are the 3 internal pharyngeal muscles?

Answer 32

Palatopharyngeus Stylopharyngeus Salpingopharyngeus

Question 33

Palatopharyngeus OIAN

Answer 33

Origin: Hard palate, palatine aponeurosis Insertion: Lateral wall of the pharynx, thyroid cartilage, oesophagus Innervation: Pharyngeal branch of vagus, pharyngeal plexus Action: Tenses the soft palate, Elevates (shorten and widens the pharynx and larynx during swallowing and speaking)

Question 34

Salpingopharyngeus OIAN

Answer 34

Origin: Cartilaginous part of the auditory tube Insertion: Blends with palatopharyngeus Innervation: Pharyngeal branch of vagus, pharyngeal plexus Action: Elevates (shorten and widens the pharynx and larynx during swallowing and speaking)

Question 35

Stylopharyngeus OIAN

Answer 35

Origin: Styloid process Insertion: Thyroid cartilage with palatopharyngeus Innervation: Glossopharyngeal (CN IX) Action: Elevates (shorten and widens the pharynx and larynx during swallowing and speaking)

Question 36

What is the arterial supply of the pharynx?

Answer 36

``` Facial artery - tonsillar artery The ascending (facial) and descending (maxillary) palatine arteries Lingual artery (external carotid) Ascending pharyngeal artery (external carotid) ``` ALL BRANCHES OF THE EXTERNAL CAROTID ARTERY

Question 37

What is the venous drainage of the pharynx?

Answer 37

External palatine vein ---> internal jugular vein

Question 38

What is the nerve supply of the pharynx?

Answer 38

Motor and sensory mainly from the pharyngeal plexus of nerves Motor- vagus to all the mm of the pharynx except stylopharyngeus (CN IX G/P) Sensory CN IX and CN V (2)