The Pharynx 2 Flashcards
Where is the stylohyoid ligament in comparision to the stylohyoid muscle?
It passes deep to this muscle.
Where does the stylohyoid ligament attach onto?
It attached onto the lesser horn of the hyoid bone.
The lesser horn also provides some attachment for the middle constrictor muscle at its origin.
What is the interior of the pharynx lined with?
Mucous membrane.
What is the mucous membrane in the nasopharynx like?
It is respiratory epithelium = pseudostratified ciliated columnar epithelium.
What is the rest of the mucous membrane like?
It is stratified squamous epithelium.
What are the 3 divisions of the cavity of the pharynx?
- the part behind the nose is the nasopharynx
- the part behind the mouth is the oropharynx
- behind the larynx is the laryngopharynx
We can see the relationship between the 3 divisions clearly on a paramedian section of the head and neck or on a lateral skull radiograph of the region.
Where does the nasopharynx lie?
Lies above the level of the palate.
How is the nasopharynx continuous of the oral part of the pharynx?
It is continuous through a narrow pharyngeal isthmus.
What does the nasopharynx communicate with in front?
It communicates with the nasal cavities.
What do the roof and the posterior wall of the nasopharynx consist off?
They consist of mucous membrane covering the bones of the base of the skull.
What is found in the submucosa of the posterior wall of the pharynx?
Lymphatics.
How is the lymphoid tissue in the nasopharynx found in children?
In children, it is enlarged where aggregations are called adenoids.
What happens if the adenoids are grossly enlarged?
They can interfere with breathing and often force a child to breathe through an open mouth and this gives the typical appearance called adenoidal facies.
Where is the opening of the auditory tube?
This is on the lateral wall of the pharynx at the level of the floor of the nose.
What does the auditory tube do?
It equalises the pressure between the pharynx and the middle ear.
When can the auditory tube be blocked?
It can be blocked in upper respiratory tract infections such as a common cold.
What is the opening of the auditory tube above and at the back bounded by?
It is bounded by a tubal ridge.
What is present in the tubal ridge?
More lymphoid tissue.
Form the tubal ridge, what can we see descending down the side wall of the pharynx?
We can see a fold of mucous membrane which contains the delicate salpingopharyngeus muscle that passes down from the auditory tube to the pharyngeal wall. This is a longitudinal muscle.
What is the name of the recess behind the tubal ridge?
The pharyngeal recess.
What the oropharynx lie behind?
It lies behind the palatoglossal fold.
What is the palatoglossal fold formed by?
It is formed by the palatoglossus muscle.
What muscle lies behind the oropharynx?
The palatopharyngeus muscle. This also raises a fold.
What are the palatoglossal and palatopharyngeus folds sometimes called?
They are sometimes called anterior and posterior pillars of the fauces.
What is present between the palatoglossal and palatopharyngeal arches?
The palatine tonsil. There is one tonsil on either side.
What are the palatine tonsils?
These are lymphoid masses.
How are the tonsilar crypts formed?
The mucous membrane on the surface of the tonsil dips deeply into the substance of the lymphoid tissue to form narrow tonsilar crypts.
What is the outer surface of the tonsil covered by?
By a thin capsule which is attached to the pharyngobasilar fascia and to the sheath of the palatoglossal muscle. This helps to keep the tonsil in place.
Where is the superior constrictor muscle in relation to the tonsils?
It is outside or lateral to them.
What nerve is lateral to the tonsilar beds?
The glossopharyngeal nerve.
When the tonsil is removed what does it have to be cut away from?
It has to be cut away from the tonsilar bed.
What is important to the tonsil?
The blood supply and venous drainage.
What is the chief artery to the tonsil a branch of?
It is a branch of the facial artery.
What part of the tonsil does the chief artery to the tonsil enter?
It enters the lower part of the tonsil.
Where do veins pierce the superior constrictor muscle?
They pierce the muscle near the chief artery to the tonsil.
Where do the veins from the tonsil terminater?
They terminate in the pharyngeal plexus of the veins or they drain into the facial vein.
When the pharyngeal plexus of veins or the facial vein bleed badly?
They bleed badly after tonsilectomy.
What is the lymphatic drainage of the tonsils like?
These are through lymphatics that pierce the superior constrictor muscle and go to the nearest lymph nodes.
When do the lymph nodes near the tonsils become enlarged and painful?
In tonsilitis. One node in particular is affected and this is called the tonsilar node or the jugulodigastric lymph node.
What are the 2 pairs of folds of mucous membranes that pass forwards from the epiglottis to the tongue called?
They are called the medial and 2 lateral glossoepiglottic folds.
What is the vallecula?
This is a depression on either side of the median fold.
Where does the laryngopharyx lie?
It lies behind the larynx.
What are the posterior and lateral walls of the laryngopharynx made of?
- They are made of the middle and inferior constrictors
- Lower fibres of the salpingopharyngeus, palatopharyngeus and stylopharyngeus muscles run longitudinally and internally.
What is the anterior wall of the laryngopharynx composed off?
It is composed of the inlet of the larynxwith the piriform fossa/ recess on either side.
Lower down what is the laryngopharynx made up of?
It is made up of the mucous membrane on the back of the cricoid cartilage.
How do the neurones that supply the muscles of the pharynx leave the brain?
They leave the brain through the cranial root of the accessory nerve (11th) and then they enter the vagus nerve (10th). The various branches of the vagus then distribute the neurones to the muscles
How is sensory supply to the pharynx like?
It varies with the level of the pharynx.
What is the mucous membrane of the nasopharynx supplied by?
It is supplied by the maxillary branch of the trigeminal nerve.
How is sensation from the oropharynx transmitted?
It is transmitted through the glossopharyngeal nerve.
Apart from transmitted sensation from the oropharynx, where else does the glossopharyngeal nerve supply?
It supplies the mucous membrane of the auditory tube
