Anatomy Flashcards
Nasal cartilages have control of the nostrils like a sphincter. TRUE/FALSE?
TRUE
WHat parts of the frontal bone and maxilla meet to frame the nasal bones?
Nasal processes of each
What bone makes up part of the nasal septum?
Perpendicular part of the ethmoid bone
What structures are formed by the palatine bone?
Posterior layers of the nasal cavity
Hard palate
What is different about the inferior nasal concha in comparison to the superior and middle?
Inferior = bone of its own
also the largest of the 3
What parts of the nasal cavity are formed by the ethmoid bone?
roof
lateral walls
septum
What Le fort fractures can cause loss of smell and increased risk of infection from the paranasal sinuses?
Le fort II & III
can disrupt the cribriform plate of the ethmoid bone
What types of epithelium are found in the nasal vestibule and nasal cavity?
VESTIBULE = Stratified squamous epithelium (Keratinised to non-keratinised)
NASAL CAVITY =
Respiratory epithelium to Olfactory epithelium
Describe the olfactory pathway
- Receptor cells in olfactory epithelium
- Pass up through cribriform plate
- Synapse with olfactory bulb (ganglion)
- Neurons pass along olfactory tract
- To Temporal lobe and olfactory areas
What nerves provide somatic sensory innervation to the nasal cavity?
Anterior ethmoidal nerve CN V1
(through anterior ethmoidal foramen)
Nasopalatine Nerve CN V2
(through sphenopalatine foramen)
Blood supply to the nose comes from both the internal and external carotid arteries. TRUE/FALSE?
TRUE
What is the name of the area of anastomosing blood vessels in the nose, prone to nosebleeds (epitaxis)
Kiesselbach’s (Little’s) Area
Apart from the 3 nasal concha, what structures are found on the lateral nasal wall?
Sphenoethmoidal recess (above superior concha)
Superior meatus
Middle meatus
Inferior meatus (below inferior concha)
What structure opens into the lateral wall of the nasopharynx?
eustachian tube (from the middle ear)
Why does congestion in the nose move between the two sides?
engorgement of the nasal mucosa changes to other side every 1-5 hours
What are the paranasal sinuses?
Open spaces within bone
Frontal sinuses
Ethmoidal air cells
Maxillary sinuses
Sphenoid sinuses
What epithelium covers the paranasal sinuses?
thin respiratory epithelium
The paranasal sinuses are normally symmetrical. TRUE/FALSE?
FALSE
not always symmetrical in normal patient
Where does the Sphenoethmoidal recess drain to in the paranasal sinuses?
Sphenoid sinus
Where does the Superior Meatus drain to in the paranasal sinuses?
Posterior ethmoidal air cells
Where does the Middle Meatus drain to in the paranasal sinuses?
Semilunar hiatus:
- Frontal sinus
- Maxillary sinus
- Anterior ethmoidal air cells
Ethmoidal Bulla:
- Middle ethmoidal air cells
Where does the Inferior Meatus drain to in the paranasal sinuses?
Nasolacrimal duct
What is sinusitis?
Inflammation of the mucosa in 1 or more of the paranasal sinuses
If a viral infection reduces the diameter or the ostia, what are the consequences?
pressure build up
orbital blow-out fracture
Why is the maxillary sinus prone to infection?
- Ostium is located superior in relation to its cavity
- Cilia must work against gravity
Tooth infection can lead to sinus infections. TRUE/FALSE?
TRUE
oro-antral fistula can allow roots to pierce upwards into maxillary sinus
Sinusitis pain can be referred to the teeth and present as ‘toothache’. TRUE/FALSE?
TRUE
if improper closure of oro-antral fistula
What are the functions of the auditory and vestibular systems?
Hearing = Auditory system Balance = Vestibular system
What is the pterion?
- H-shaped suture
- Frontal, parietal, temporal and sphenoid
- Thinnest part of skull
What cranial nerve is associated with the Stylomastoid foramen?
CN VII
Pathology in the internal acoustic meatus (e.g. an acoustic neuroma) could damage which cranial nerves?
CN VII and CN VIII
What are the functions of the external, middle and inner ear?
External - Collects and conveys sound waves to tympanic membrane
Middle - Amplifies & conducts sound waves to the internal ear
Inner - Converts special sensory information
The external ear is avascular. TRUE/FALSE?
TRUE
Describe the composition of the ear canal starting at the external acoustic meatus
1/3 cartilage, 2/3 bony
What glands in the ear canal produce earwax?
ceruminous glands
What cranial nerves make up the tympanic membrane?
CN V3
CN X
What superficial lymph nodes are responsible for lymphatic drainage of the ear?
- parotid
- mastoid
- superficial cervical lymph nodes
The petrous portion is a part of which bone in the skull?
temporal bone
What are the functions of CN VII?
Motor to face and stapedius
Taste to anterior 2/3 of tongue
Secretomotor to salivary glands and lacrimal gland
Sensation to external ear
What structures pass through the internal acoustic meatus?
CN VII (Facial nerve) CN VIII (Vestibulocohlear nerve) Labyrinthine artery (+ vein)
The labyrinthine artery is a branch of which artery?
Anterior inferior cerebellar artery
What are the names for the thick and thin parts of the tympanic membrane?
Pars flaccida = thin
Pars tensa = thick
What cranial nerves supply the internal and external surface of the tympanic membrane?
External surface: mostly CN V3
Internal surface: CN IX
What structures are provided sensory innervation by CN IX?
Middle ear cavity Eustachian tube Nasopharynx Oropharynx Tonsils
What are the 3 bones found in the middle ear?
Malleus (hammer)
Incus (anvil)
Stapes (Stirrup)
What muscles are found in the inner ear?
Stapedius
Tensor tympani
What type of joint is found in the middle ear between the ossicles?
synovial joint
Where is the base of the stapes found?
In the oval window
What is the aditus?
Aditus* (doorway into) the mastoid antrum from the epitympanic recess
What two structures does the eustachian tube connect?
Connects anterior wall of the middle ear cavity to nasopharynx
Where is the internal acoustic meatus located?
The pontomedullary junction
What are the 4 axon modalities of the facial nerve?
Special sensory
sensory
motor
parasympathetic
Chorda tympani is a branch of which cranial nerve?
CN VII
What is supplied by the chorda tympani?
Taste buds of the anterior 2/3rds of the tongue
Parasympathetic to submandibular & sublingual salivary glands
How does the stapedius muscle dampen excessive noise?
Reduces stapes movement to protect the internal ear from excessive noise
The chorda tympani piggy backs on what other cranial nerve?
lingual nerve branch of CN V3
What are the muscles of facial expression?
Frontalis
Orbicularis oculi
Elevators of lips
Orbicularis oris
Asking the patient to complete what facial movements will test the muscles of facial expression and their innervation?
Frown
Close eyes tightly
smile
Maintain air in puffed out cheeks
What is the otic capsule?
surrounds the structures of the inner ear
Otic capsule bone is denser than the surrounding temporal bone. TRUE/FALSE?
TRUE
What type of fluid is found between the bony and membranous labyrinths in the inner ear?
Perilymph (like ECF => high Na, Low K)
What fluid is found inside the membranous labyrinth in the inner ear?
Endolymph (like ICF -> Low Na, High K)
What is the other word for the apex of the cochlear spiral?
Cupula
How many semicircular canals are found in one ear and what are they named?
Superior
Lateral
Posterior
What is the name given to clusters of hair cells?
regions called maculae
How is sound transmitted in the inner ear?
- Sound waves make tympanic membrane vibrate
- Vibrations transmitted through ossicles
- Base of stapes vibrates in oval window
- Vibration of stapes creates pressure waves in perilymph
- Hair cells in cochlea are moved, APs stimulated and conveyed to brain by cochlear nerve
- Pressure waves descend and become vibrations again
- Pressure waves are dampened at round window
The cochlear duct is suspended by the spiral ligament and splits the cochlear canal into what 2 parts?
Scala vestibuli
Scala tympani
