How does the hyoid apparatus contribute to swallowing?
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The hyoid apparatus pulls the larynx forward.
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How does the hyoid apparatus contribute to swallowing?
The hyoid apparatus pulls the larynx forward.
What type of epithelium lines the laryngopharynx?
Stratified squamous epithelium.
Where do all the pharyngeal wall muscles insert?
Onto the roof of the pharynx, specifically the dorsal and lateral arches.
Which muscle raises the soft palate during swallowing and mouth breathing? Location within soft palate?
The Levator veli palatini muscle. Within caudal side wall
What is the external carotid artery responsible for?
Supplying blood to the face and neck.
Muscle inside guttural pouch (NOTE LC and MC are lateral and medial compartments)
Longus capitus muscle
What is the rostral and caudal margin of the oropharynx?
The rostral margin is the oral cavity. Caudal is laryngopharynx
What type of epithelium lines the oropharynx?
The oropharynx is lined with stratified squamous epithelium.
What is a proposed function of the guttural pouch in horses?
It may cool blood to the brain.
What is the process of swallowing called?
Deglutition
What are the dorsal and ventral margins of the oropharynx?
The dorsal margin is the soft palate and the ventral margin is the tongue.
What is the rostral margin of the laryngopharynx?
The free tip of the soft palate.
What are the main divisions of the pharynx?
The main divisions of the pharynx are the nasopharynx, oropharynx, and laryngopharynx.
Which muscle within the main body of the soft palate shortens it?
The Palatinus muscle.
What is the name of the single muscle associated dilation of the with the pharyngeal wall?
Stylopharyngeus caudalis.
What is located at the caudal margin of the nasopharynx?
The caudal margin of the nasopharynx is the laryngopharynx.
What is the surgical access point for the guttural pouch in veterinary medicine? (less common - usually done endoscopically)
Viborg’s triangle
What are the margins of the guttural pouch in horses?
The dorsal margin is the base of the skull. Ventral: laryngopharynx and oesophagus. Lateral: skin. Medial: septum
What is the pharynx?
The pharynx is a common cavity for food and ingesta, connecting the oral cavity ventrally with the esophagus dorsally, and the nasal cavity dorsally with the larynx and trachea ventrally.
Cranial nerves passing through / near the guttural pouch which can be seen in the image
Cranial nerve IX (glossopharyngeal), X (vagus), XII (hypoglossal)
What role does the palatopharyngeal arch play in swallowing?
The palatopharyngeal arch constricts.
What is the rostral margin of the nasopharynx?
The rostral margin of the nasopharynx is the choanae, which is the opening of the nasal cavity into the nasopharynx.
What is the nasopharyngeal recess (D on diagram)? Note also on diagram, R and L are entrances to the guttural pouch
It is a caudodorsal extension of the nasopharynx found in most ungulates, and it is blind ending.
What forms the caudal margin of the laryngopharynx?
The larynx and the opening of the oesophagus.
What type of muscles make up the pharyngeal wall?
Striated muscles.
Blood vessels passing through / near the guttural pouch which can be seen in the image
Internal carotid artery, external carotid artery
How can the guttural pouch in horses be accessed?
The guttural pouch can be accessed through slits that drain into the nasopharynx.
What is a bacterial disease associated with the guttural pouch in horses?
Strangles caused by Streptococcus equi subsp. equi.
What are the three regions of the pharyngeal wall muscles?
Rostral (Palatopharyngeal), Middle (Hypopharyngeal), Caudal (Thyropharyngeal).
Which nerves are responsible for the innervation of the pharyngeal wall?
Vagus nerve (X) and hypoglossal nerve (XII).
What are the two compartments that the stylohyoid bone divides into?
Lateral and medial compartments.
What is the function of the pharyngeal wall muscles?
Important for the passage of food
What is the ventral margin of the nasopharynx?
The ventral margin of the nasopharynx is the soft palate, which is soft tissue continuous with the palatine bone.
What is the location of the auditory tube in all species?
The auditory tube runs from the nasopharynx to the middle ear.
What are the signs of fungal mycosis in the guttural pouch?
Signs depend on the location of plaques, such as epistaxis if over an artery or neurological disease if over a nerve.
What is the primary function of the soft palate?
The soft palate divides the pharynx.
Lymph node visible in guttural pouch
Pharyngeal lymph node
What does the epiglottis do during swallowing?
The epiglottis flips back to cover the tracheal opening.
What is the guttural pouch in horses?
The guttural pouch is a large diverticulum of the auditory tube.
What are the lateral and dorsal margins of the laryngopharynx?
The pharyngeal wall.
What type of structure is the soft palate?
The soft palate is a flexible muscular structure.
What is the role of the Tensor veli palatini muscle? How is it located in the soft palate?
It causes lateral traction and tension on the soft palate. Within rostral side wall
Which nerve innervates the soft palate?
The mandibular branch of the trigeminal nerve.
What action does the tongue perform in the swallowing process?
The tongue pushes food into the esophagus.
What type of epithelium lines the nasopharynx?
The nasopharynx is lined with respiratory epithelium.
What forms the lateral and dorsal margins of the nasopharynx?
The lateral and dorsal margins of the nasopharynx are formed by the pharyngeal wall.
Airflow in the head! See on image how air passes through the nasal and oral cavities
See image
Notable information about the anatomy of the pig's soft palate
Has long soft palate (past trachea, almost into oesophagus)
Bottom image shows dorsal displacement of the soft palate - the other two are normal
See image
Swallowing process - lengthy 5-step description
Soft palate elevated to obstruct nasopharynx and open oropharynx
Palatopharyngeal arch constricts
Hyoid apparatus pulls larynx forward
Epiglottis flips back to cover tracheal opening
Tongue pushes food into oesophagus
Three structures that make up Viborg's triangle
Ramus of mandible, Sternomandibularis muscle, linguofacial vein
