Nasal anatomy and physiology Flashcards
primary function of the nose
airway in respiration
Group who are obligate nasal breathers
neonates
Sinonasal mucosa epithelium type
respiratory ciliated columnar epithelium with goblet cells
List as many other functions of the nose as you can
olfaction
warming of inspired air and humidification
filtration of large particles by vibrisae/coarse hairs in nasal vestibule
mucus production, trapping and cilia clearance
immune protection
drainage/aeration of middle ear by Eustachian tube
voice modification
drainage of paranasal sinuses and nasolacrimal duct
pheromone detection via vomero-nasal organ of Jacobson
Nasolacrimal duct common name
tear duct
What does the Eustachian tube link?
middle ear and nasopharynx
Pheromone
Chemical an animal produces which another animal can detect and hence alter their behaviour
3 functions of sinuses
Reduce skull weight and facial bones
help with vocal resonance
act as a buffer for trauma
What are paranasal sinuses?
air cavities in the facial bones
List the parts of the external nose
glabella, nasion, dorsum, supratip, tip, columnella
Clinical conditions of external nose
deformity
congenital
acquired eg trauma
Bony and cartilage fractions of the nose and what bones are involved
1/3 bone - frontal and maxillary
2/3 cartilage
Midline partition of inner nose
nasal septum
Lateral wall structures inside nose
turbinates
roof of internal nose
cribriform plate of ethmoid bone
floor of internal nose
hard palate
Associated structures of the internal nose
paranasal sinuses and nasopharynx
3 turbinates
superior, middle, inferior
Meatus association with turbinates
found inferior to associated turbinate
What turbinate can cause the most problems? Examples
inferior - inflammation or infection by allergic rhinitis
topical steroids and reduction surgery
Name the paranasal sinuses
frontal, maxillary, ethmoid - posterior and anterior, sphenoid
What meatus drains most of the paranasal sinuses?
middle
List meatus and what paranasal sinuses are drained
superior - posterior ethmoid and sphenoid
middle - frontal, maxillary, anterior ethmoid
inferior - nasolacrimal duct
Important relations of each paranasal sinus
frontal + ethmoid = anterior cranial fossa
maxillary - orbits
sphenoids - ICA, optic nerve, cavernous sinus
Rhinosinusitis
Inflammatory and infective process effecting the nasal passage and para nasal sinuses
types of rhinosinusitis
Acute (bacterial) <12 weeks
Chronic - allergic or non allergic
non allergic is with or without polyps
Importance of paranasal sinuses
infection spread eg meningitis, intracranial abscess, orbital sepsis
surgery risk eg CSF leak, orbital complications leading to blindness
Anterior nasal supply
branches of ICA
ophthalmic –> anterior/posterior ethmoid arteries
Posterior nasal supply
branches of ECA
sphenopalatine
What is little’s area and why is it important?
When ECA and ICA branches meet - sphenopalatine, anterior and posterior ethmoid arteries, greater palatine and superior labial artery
epistaxis
Epistaxis
Nose bleeds
Nose bleeds causes
Trauma - nose picking Anticoagulants iatrogenic - surgery idiopathic hypertension
Important nerves
trigeminal
olfactory - smell
facial nerve - innervate pterygoid canal
Anosmia
loss of sense of smell
