Nasal Cavity Flashcards
Dorsum
-extends from root to apex, in midline of the nose
what are the inferior apertures of the nose?
-the nares(nostrils)
Each nostril is lined laterally by…
-ala of the nose
supporting framework of the nose is composed of…
bone and hyaline cartilage
what does the bony framework support and what bones does it consist of?
- supports the upper part of the nose
- consists of nasal bones and frontal process of maxillae
what does the cartilaginous framework support and what does it consist of?
- supports lower part of the nose
- consists of one septal and two major alar cartilages
what are cartilages connected to each other and bones by?
-fibrous tissue
septal cartilage forms what?
-anterior part of the nasal septum
how many lateral processes does the septal cartilage have>
2
-located below inferior border of the nasal bones
major alar cartilages
- u shaped
- form lateral and medial borders of nostrils
what is another word for borders of the nostrils?
-crura
what is the chamber of the nasal cavity covered with?
-mucosa
what divides the nasal cavity into right and left parts
-nasal septum
how does the nasal cavity communicate with the pharynx?
-posterior nasal apertures(choanae)
vestible
- area immediately above nares
- lined with skin and contains stiff hair
what are the functions of the nasal cavity?
- olfaction
- conditioning inspired air
- secretions from paranasal air sinuses and nasolacrimal duct drain into it
what is superior to the nasal cavity
anterior cranial fossa
what separates the anterior cranial fossa and the nasal cavity?
the cribriform plate
what is lateral to the upper part of the nasal cavity?
-ethmoidal air cells and orbit
what is lateral to the lower part of the nasal cavity
-maxillary sinus
what is inferior to the nasal cavity>
-oral cavity
what separates the oral cavity and the nasal cavity?
-hard palate
what is posterior to the nasal cavity?
-nasopharynx
what forms the floor of the nasal cavity
-hard palate(palatine processes of maxillae and horizontal plates of palatine bones)
what forms the roof of the nasal cavity?
(from anterior to posterior)
- nasal bone
- nasal spine of frontal bone
- cribriform plate of ethmoid
- anterior and inferior aspects of body of sphenoid
what forms the medial wall of the nasal cavity
-perpendicular plate of ethmoid and vomer
what makes up the lateral wall of the nasal cavity?
- maxilla
- lacrimal bone
- inferior nasal concha
- ethmoidal labyrinth
- perpendicular plate of palatine
- medial pterygoid plate
what is the meatus?
-space between each concha and lateral wall
conchae
- superior, middle, inferior
- 3 scroll-like bony projections
which conchae is part of the ethmoid bone and which is its own bone?
- superior and middle are part of the ethmoid
- inferior is its own bone
sphenoethmoidal recess
- part of nasal cavity located above and behind superior nasal conchae
- receives opening of sphenoidal sinus
in the superior meatus, what opens up via small orifices in its lateral wall
-posterior ethmoidal air cells
ethmoidal bulla
-elevation in lateral wall of middle meatus caused by middle ethmoidal air cells
semilunar hiatus
-curved cleft anterior and inferior to ethmoidal bulla
where is the ostium of maxillary sinus located?
-lower part of semilunar hiatus
Infundibulum
curved channel that the superior end of semilunar hiatus leads into
what does the infundibulum receive?
-openings of anterior ethmoidal air cells
what is the options about the opening of the frontal sinus and the infundibulum?
- some receive opening of frontal sinus
- in others, the infundibulum has superior blind end, and frontal sinus opens directly into anterior part of middle meatus
what is located in the anterior part od the inferior meatus lateral wall?
-opening of nasolacrimal duct
nasal mucosa lines the entire nasal cavity EXCEPT
vestibule
nasal mucosa is firmly bound to…
periosteum and perichondrium of supporting structures
nasal mucosa is continuous with the mucosal lining of…
nasopharynx, paranasal air sinuses, and nasolacrimal duct
what are the types of mucosa?
- olfactory
- respiratory
olfactory mucosa
- lines highest part of roof and adjacent parts of septum and lateral wall
- contains olfactory receptor cells
respiratory mucosa
- lines rest of the nasal cavity
- ciliated, pseudostratified, columnar epithelium
- has goblet cells
branches from what two nerves provide general sensory nerve supply to the nasal cavity?
-ophthalmic and maxillary nerves
what is the anterior ethmoidal nerve a branch of?
-nasociliary nerve(from the ophthalmic nerve)
the anterior ethmoidal nerve passes from the orbit to the anterior cranial fossa via…
-anterior ethmoidal foramen
what does the anterior ethmoidal nerve run forward on?
cribriform plate
the anterior ethmoidal nerve leaves the anterior cranial fossa and enters the nasal cavity via…
small slit at the side of the crista galli
what does the internal branch of the anterior ethmoidal nerve supply?
-mucosa of anterior parts of septum and lateral wall
what does the external branch of the anterior ethmoidal nerve supply?
-skin of the lower part of nose
what does the nasal branches of infraorbital nerve supply?
skin of vestibule
what does the nasal branch of anterior superior alveolar nerve supply?
mucosa of anterior part of inferior meatus
what does the posterolateral nasal branch supply?
- originate from pterygopalatine ganglion or greater palatine nerve
- supply mucose of posterior part of the lateral wall
what does the nasopalatine nerve supply
posterior part of nasal septum
What kind of neurons are olfactory receptor cells?
Bipolar neurons located in olfactory mucosal
olfactory receptor cells are what kind of neurons? located where?
bipolar neurons located in olfactory mucosa
peripheral process of olfactory receptor cells
- dendrites
- reach mucosa surface and give rise to nonmotile cilia, which spread over mucosal surface
central processess of olfactory receptor cells
- axons
- join to form olfactory nerves
- pass through openings of cribriform plate
- end in olfactory bulb
what are the main arteries that supply the nasal cavity?
-sphenopalatine and anterior ethmoidal arteries
sphenopalatine artery
- terminal branch of maxillary artery
- supplies posterior parts pf lalteral wall and septum
anterior ethmoidal artery
- branch of ophthalmic artery
- supplies anterior parts of lateral walls and septum
minor arterial sources for nasal cavity
- posterior ethmoidal artery
- superior labial artery
- greater palatine artery
Kiesselbach’s area
- where the arteries all anastomose together
- common site for epistaxis (nose bleed)
where is the vein plexus for the nasal cavity?
submucosa
where does the venous drainage go?
- pterygoid venous plexus(via sphenopalatine vein)
- facial vein and superior ophthalmic vein(via anterior and posterior ethmoidal veins)
paranasal sinus
air spaces in frontal, maxilla, ethmoid, and sphenoid bones, lined by a mucous membrane continuous with that of nasal cavity
how do sinuses develop?
- as evaginations of nasal mucosa
- mucosa invades bones surrounding nasal cavity, with secondary bone resorption around invading mucosal sacs
paranasal sinuses are __________ at birth
-rudimentary
growing of the paranasal sinuses
- there is a slow, continuous growth during childhood and a rapid growth during adolescence
- sinuses are max size as adult
functions of paranasal sinuses
- resonating chambers for voice
- lighten skull bones (they are hollow)
maxillary sinus
- LARGEST paranasal sinus
- lies in body of maxilla
- base is directed medially
- apex is directed laterally
what is superior to the maxillary sinus
orbit and all its contents
what is medial to the maxillary sinus
nasal cavity
why is there poor drainage in the maxillary sinus?
-maxillary ostium is located high in the medial wall of the nasal cavity so the erect posture makes for bad draining
what is inferior to the maxillary sinus?
-maxillary alveolar process and roots of maxillary teeth
what roots are closer to the maxillary sinus, molar of incisor?
molar
how does the maxillary sinus communicate with the middle nasal meatus?
by an opening located in lower part of semilunar hiatus
nerve supply to the maxillary sinus
superior alveolar nerves (from V2)
Blood supply to the maxillary sinus
superior alveolar arteries (branches of maxillary and infraorbital arteries)
where are the frontal sinuses located?
-within frontal bone, behind superciliary arches
where do the frontal sinuses extend?
superiorly into frontal squama and posteriorly into orbital plates
where do frontal sinuses open to?
middle nasal meatus
Nerve supply to frontal sinuses
supraorbital nerve (branch of frontal nerve from V1)
blood supply to frontal sinuses
supraorbital artery (branch of ophthalmic artery
ethmoidal air cells
- thin walled spaces within ethmoidal labyrinths
- number of cells varies from 3-18
anterior ethmoidal air cells
-open into infundibulum of middle nasal meatus
middle ethmoidal air cells
-open on surface of ethmoidal bulla of middle nasal meatus
posterior ethmoidal air cells
-open into superior nasal meatus
nerve supply of ethmoidal air cells
anterior and posterior ethmoidal nerves (branches of nasociliary nerve, from V1)
Blood supply for ethmoidal air cells
anterior and posterior ethmoidal arteries (branches of ophthalmic artery)
where are sphenoidal sinuses located?
- posterior to upper part of nasal cavity, within body of sphenoid
- superior to pituitary gland and optic chiasm
- laterally to cavernous sinus and internal carotid artery
where do sphenoidal sinuses open?
open into corresponding sphenoethmoidal recess
nerve supply for sphenoidal sinuses
- posterior ethmoidal nerve
- pharyngeal nerve
blood supply for sphenoidal sinuses
- posterior ethmoidal artery
- pharyngeal branch of maxillary artery
