Head and Neck Flashcards
What comprises the anterior cranial fossa?
cribiform plate, crista galli, lesser wing of sphenoid, orbital surface
what comprises the middle cranial fossa?
optic canal, superior orbital fissure, foramen rotundum, formen ovale, superior orbital fissure, pituitary fossa
what comprises the posterior cranial fossa?
internal acoustic meatus, jugular foramen, hypoglossal canal, clivus, foramen magnum
What is the function of nasalis (transverse part)?
It compresses the nares
What is the function of procerus?
it pulls the eyebrows down
what is the function of zygomaticus major?
it draws the angle of the mouth superiorly
what is the function of the buccinator muscle?
pulls the cheek inwards
what is the function of the labii superioris?
it elevates the upper lip
What nerve innervates the muscles of facial expression?
Facial nerve (cranial nerve 7)
which cranial foramina does the facial nerve pass through?
internal acoustic meatus
What are the main divisions of the facial nerve?
temporal, zygomatic, buccal, marginal mandibular, cervical
Where do the 5 main divisions of the facial nerve arise?
the parotid salivary gland
what is the function of the temporalis (horizontal fibres)
it retracts the mandible
what is the function of the masseter?
it elevates the mandible
what is the function of the lateral pterygoid?
it depresses the mandible
what is the function of the medial pterygoid?
it protrudes the mandible
what nerve innervates the muscles of mastication?
the mandibular branch of the trigeminal nerve (cranial nerve 5)
which cranial foramen does the trigeminal nerve exit through?
foramen ovale
Name the muscles of mastication
temporalis, masseter, medial pterygoid and lateral pterygoid
Name the muscles of facial expression
occipitofrontalis, orbicularis occuli, corrugatpr supercilii, nasalis, procerus, depressor septi nasi, orbicularis oris, buccinator, depressor anguli oris, levator anguli oris, risorius, zygomaticus major, zygomaticus minor, levator labii superioris, levator labii superioris alaeque nasi, depressor labii inferioris , mentalis, platysma
what is the action of the platysma?
it depresses the mandible and angle of mouth
what is the action of the trapezius?
elevates the scapula, retracts the scapula, depresses the scapula, rotates the scapula
what is the function of the sternocleidomastoid?
cervical rotation, cervical flexion
what nerve supplies the trapezius and the sternocliedomastoid?
the accessory nerve (cranial nerve 11)
How would you examine cranial nerve 11?
Ask the patient to shrug their shoulders and rotate their head against resistance
What is different about the origin of the left and right common carotid arteries?
the left common carotid typically emerges immediately from the arch of the aorta, whereas the right common carotid arises from the brachiocephalic/innominate artery an intermediate branch between the arch of the aorta and right common carotid
At what vertebral level do the common carotids bifurcate?
C3/C4
which vessel (internal or external carotid) supplies structures within the neck and face?
external carotid
where does the internal jugular vein begin?
as a continuation of the sigmoid sinus, at the jugular foramen
which structures can be found within the carotid sheath?
internal jugular vein, common carotid artery, vagus nerve
where do the internal jugular veins drain to?
left and right brachiocephalic veins respectively, the internal jugular unites with the subclavian
which specialised system drains venous blood from the brain and meninges back towards the internal jugular veins
internal dural venous system
Which 6 extra-occular muscles are responsible for the movement of the eyeball?
4 x rectus (superior, inferior, medial, lateral)
2 x oblique muscles (superior, inferior)
Which structures on the lateral wall of the nasal cavity assist with heating air?
nasal conchae (superior, middle, inferior)
which structures form the nasal septum?
perpendicular plate of ethmoid, vomer, and nasal septal cartillage
what are the names of the paranasal sinuses?
maxillary, frontal, sphenoid, and ethmoid sinuses
what are the boundaries of the oral cavity?
superior - hard and soft pallate
inferior - muscular diaphragm (mylohyoid muscles) and tongue
medial and lateral - buccinator muscles lined by oral mucose
at which point do the nasal cavities and oral cavity become continuos?
nasopharynx
what is Waldeyer’s ring and which structures associated with this can be found within the oral cavity?
a ring of lymphoid tissue found in the throat, consisting of pharyngeal tonsil (adenoid), tubal tonsils, palatine tonsils, lingual tonsils
what is the start and end of the nasopharynx?
base of sphenoid sinus to soft pallate
what is the start and end of the oropharynx?
tip of soft pallate to tip of epiglottis
what is the start and end of the laryngopharynx?
Tip of epiglottis to the inferior border of cricoid cartillage
What are the circular muscles of the pharynx?
superior, middle, inferior constrictor
what is the fucntion of the circular muscles of the pharynx?
decrease the diameter of the pharynx and propel food along the pharynx towards the oesophagus
what are the longitudinal muscles of the pharynx?
stylopharyngeus
salpinopharygneus
palatopharyngeus
what structures does the thyrohyoid membrane run between?
thyroid cartillage and hyoid bone
what structures does the cricothyroid ligament run between?
cricoid cartilage and thyroid cartilage
what is the action of the cricothyroid muscle and how does it effect phonation
action - tension and elongation of the vocal folds, results in higher pitch phonation
what are the notable differences in the course of the vagus nerve between the left and right sides of the neck?
the vagus nerve travels bilaterally down the neck, within the carotid sheath, on the left hand side the nerve descends into the thorax and gives off the recurrent laryngeal nerve after coursing around the arch of the aorta. on the right hand side the vagus nerve courses around the right subclavian artery before giving rise to the recurrent laryngeal nerve
