Nasal: Anatomy and Physiology Flashcards
what is the nasal function?
> airway in respiration (neonates are obligate nasal breathers) > warming inspired air > humidification > filtration of large particular matter > mucus production, trapping and ciliary clearance > immune protection > olfaction > drainage > voice modification > pheromone detection
describe sinoasal mucosa
respiratory ciliated columnar epithelium with goblet cells
what does the nose drain?
> middle ear via Eustachian tube
> paranasal sinuses and nasolacrimal duct
what are the functions of the sinuses?
debatable:
> vocal resonance?
> decrease weight of skull and facial bones?
> buffer for trauma?
name the different parts of the external nose shape
> glabella > nasion > dorsum > supratip > tip > collumnella
name the three structures that make up the external nose
> nasal bone
upper lateral cartilage
lower lateral cartilage
what fraction of the nose is made up from bone?
1/3
what bones make up the nose?
frontal processes of the maxilla and nasal parts of the frontal bones
what is the middle partition of the internal nose?
nasal septum
what makes up the lateral walls of the internal nose?
turbinates
what makes up the roof of the nose?
cribriform plate
what makes up the floor of the internal nose?
the hard palate
what structures are associated with the internal nose?
> paranasal sinuses
> nasopharynx
what abnormalities can there be associated with the nasal septum?
> deviation (congenital or acquired)
septal perforation
septal haematoma
what are turbinate’s?
bony scroll like projections form the lateral wall of the nose (superior, middle ad inferior)
what is each turbinate associated with?
its respective meatus (passage leading to the interior of the body)
how may turbinates lead to nasal blockage?
infection and inflammation
how are turbinate blockage usually managed?
with topical steroids or surgically with turbinate reduction surgery
name the paranasal sinuses
> frontal
maxillary
ethmoid (anterior and posterior)
sphenoid
what is the inferior meatus?
nasolacrimal duct?
what makes up the middle meatus?
frontal, maxillary and anterior ethmoid
what makes up the superior meatus?
posterior ethmoid and sphenoid
what is rhino sinusitis?
a concurrent inflammatory and infective process that affects the nasal passageway and contiguous para nasal sinuses
what are the different categories of rhino sinusitis?
> acute
chronic:
-allergic
-non allergic (with or without polyps)
what are the important relations of the sphenoid sinus?
> optic nerve
internal carotid artery
cavernous sinus
what sinus are the orbits related to?
maxillary sinus
what are the frontal and the ethmoid sinuses related to?
anterior cranial fossa
what is the relevance of the anatomical relations of the sinuses?
> infection can spread through the; meninges, intracranial abscess and orbital sepsis
surgical risk; CSF leak, orbital complications
describe the anterior nasal blood supply
derived from branches of the internal carotid artery
describe the posterior nasal blood supply
derived from branches of the external carotid artery: sphenopalatine artery
what areas causes most nosebleeds?
littles area
what can cause nosebleeds?
> trauma > anticoagulants > iatrogenic > idiopathic > hypertension
what nerve supplies the nose?
trigeminal nerve
what can cause olfactory dysfunction?
> rhinosinusitis
postviral anosmia
trauma
what does the olfactory bulb have a direct communication to?
the brain
