Neck, Nasal Cavity, Middle Ear Flashcards
Name the 5 suprahyoid muscles
Anterior belly of the digastric muscle, posterior belly of the digastric muscle, stylohyoid, mylohyoid, and glenohyoid
Which suprahyoid muscles are innervated by the nerve to mylohyoid (V3)?
Anterior belly of the digastric muscle and the mylohyoid muscle
Which suprahyoid muscles are innervated by the facial nerve (VII)?
Posterior belly of the digastric muscle and the the stylohyoid
What are the 2 main functions of the suprahyoid muscles?
They raise the hyoid bone and depress the mandible
Name the 4 infrahyoid muscles
Omohyoid, Sternohyoid, Sternothyroid, and Thyrohyoid
What is the main function of the infrahyoid muscles?
They depress the hyoid bone
What does the ansa cervicalis (C1-C3) innervate?
omohyoid, sternohyoid, and sternothyroid
What is the thyrohyoid innervated by?
N. to thyrohyoid (from C1)
What is the ansa cervicalis?
superior and inferior roots that originate from C1 and C2-C3 respectively and combine to form a nerve loop
What are the three main tributaries of the internal jugular vein?
common facial vein (the junction of the facial vein and the retromandibular vein), superior thyroid vein (drains the superior part of the thyroid gland), and the middle thyroid vein (drains the inferior part of the thyroid gland)
What are the three harder to see tributaries of the internal jugular vein?
the lingual vein (drains tongue), pharyngeal vein (drains pharynx via pharyngeal venous plexus), and occipital vein (drain posterior part of scalp)
What are the 8 direct branches of the external carotid artery?
Superior thyroid artery, Ascending pharyngeal artery, Lingual artery, Facial artery, Occipital artery, Posterior auricular artery, Superficial temporal artery, Maxillary artery
What are the two terminal branches (most superior position of neck) of the external carotid artery?
Superficial temporal and maxillary arteries
What is the first branch of the external carotid artery (down at the bottom of the neck)?
Superior thyroid artery
Thyroid surgery causes damage to the ______ nerve or _____ nerves because they are closely entangled in the ______ arteries.
recurrent, external laryngeal, inferior thyroid
Bilateral injury in thyroid surgery results in _____ and/or ________ spasm.
aphonia (no voice), laryngeal
Removal of parathyroid glands can result in what due to decline in what?
It can cause tetany ( severe convulsions) due to decline in serum calcium levels
What drains into the superior meatus?
the posterior ethmoid cells
What drains into the middle meatus?
The frontal sinus, middle ethmoid air cells, and maxillary sinus
What drains into the inferior meatus?
The nasolacrimal duct
What is the nasal cavity space that drains the sphenoidal sinus?
The sphenoethmoidal recess (which is between the superior concha and nasal roof)
What is CSF Rhinorrhea?
When CSF leaks into the nasal cavity due to a compromised cribriform plate
What are the three causes for CSF Rhinorrhea?
head trauma, complications of ear/nose surgery, or spontaneously from chronic elevated intracranial pressure
What are two possible symptoms of CSF Rhinorrhea?
salty post-nasal drainage or severe headache eased by intermittent clear fluid drainage(rhinorrhea)
What is a possible complication of CSF Rhinorrhea?
meningitis
Infection in the nasal cavity can reach what five places?
anterior cranial fossa via the cribriform plate, nasopharynx and retropharyngeal space, middle ear via the pharyngotympatic tube, paranasal sinuses, and the orbit via the nasolacrimal duct
Infection from the sphenoidal sinus can reach what two places?
the pituitary fossa and cavernous sinus
Infection from the ethmoidal sinus (and any other sinus, but mostly the ethmoidal) can reach what?
the orbit
Infection from the frontal, ethmoidal and sphenoidal sinuses can potentially reach the cranial cavity to cause what two things?
meningitis or intracranial abscess
What are the 6 openings in the nasal cavity?
- cribriform plate (where CN1 and posterior ethmoidal vessels pass through)
- anterior ethmoidal canal (between the cribriform plate and surrounding bone)
- foramen caecum (only in some individuals between the crista galli and frontal bone)
- sphenopalatine foramen (in posterolateral wall of superior nasal meatus and is a route of communication between the nasal cavity and pterygopalatine fossa)
- Incisive canal (in the maxilla just lateral to the nasal septum)
- nares
What are the 6 different surfaces of the ethmoid bone?
- Ethmoid labyrinths: two rectangular boxes united superiorly by the cribriform plate
- Cribriform plate: perforated sheet of bone at apex of nasal cavities that separates nasal cavities from cranial cavity
- Perpendicular plate: sheet of bone descending vertically from cribriform plate to form nasal septum
- Orbital plate: forms medial wall of orbit
- Superior and middle conchae: projections across nasal cavity
- Ethmoid bulla: middle ethmoidal air cells form a bulge located inferior to origin of middle concha
What bones do the ethmoid labyrinths articulate with?
- superior surface with frontal bone
- anterior surface with maxilla and lacrimal bones
- inferior surface with maxilla bones
What are the three regions of each nasal cavity?
from top to bottom: olfactory region, respiratory region, and nasal vestibule
Which nasal cavity region is the largest and what’s inside it?
respiratory region, and it has a rich neurovascular supply and is lined by an epithelium composed of ciliated and mucous cells
What are choanae and what forms it?
posterior nasal apertures that are formed by sphenoid bone and its medial pterygoid plates, vomer, and palatine bones
Where is the external ear located in the skull?
In the the external auditory meatus ( it combines with the auricle: cartilaginous part of ear, and continues through auditory canal to tympanic membrane)
Where is the middle ear located in the skull?
the cavity within the petrous portion of the temporal bone
Where is the inner ear located in the skull?
series of cavities in the petrous part of temporal bone between middle ear and internal acoustic meatus
What are the three ossicles in the middle ear?
Malleus, incus, stapes
What are the two muscles of the middle ear?
tensor tympani and stapedius
What does the tensor tympani do?
It dampens the vibrations of the tympanic membrane
What does the stapedius do?
It dampens the oscillations of the staples
What is the primary function of the middle ear?
The middle ear is an air-filled space lined by mucosa that is primarily for mechanical conduction of sound to fluid-filled internal ear
What’s inside the cochlea of the inner ear?
The cochlear duct with the organ of hearing
What’s inside the semicircular canals of the inner ear?
The semicircular duct with the organ of balance
What’s inside the ventricle of the inner ear?
The utricle and saccule with the organ of balance
What is otitis media?
infection with inflammation of the ear which results in fluid build up in the middle ear, and puts pressure on the tympanic membrane
What are two causes of otitis media?
- viral respiratory infections (that pass through the pharyngotympanic tube to middle ear)
- enlarged adenoids (that block the pharyngotympanic tube)
What are 6 symptoms of otitis media?
pain, fever, headache, clear fluid draining from external ear, dizziness, hearing loss
What are the complications of otitis media?
eardrum rupture, permanent damage to tympanic membrane, hearing loss
What two structures pass through the middle ear but do not innervate it?
1) lesser petrosal n (which is a branch of tympanic plexus) en route to the otic ganglion
2) chorda tympani n (branch of facial n) en route to submandibular ganglion
What structures innervate the middle ear?
GE: the nerve to stapedius (VII) to innervate stapes and nerve to medial pterygoid (V3) to innervate tensor tympani muscle
GA and VE: the tympanic plexus (innervates mucosa of middle ear, mastoid air cells, and pharyngotympanic tube)