Nose Flashcards
nostrils/nares
two elliptical, external orifices of external nose
ala nasi
lateral margin of external nose, which is rounded and mobile
bony elements of nose
nasal bones
frontal processes of maxilla
nasal part of frontal bone
primary muscles of external nose
compressor nasalis
dilator naris
levator labii superioris alaeque nasi
all are innervated by facial nerve
blood supply of external nose
skin of external nose: ophthalmic artery & maxillary artery
skin of ala and lower part of septum: facial artery
external nose sensory innervation
bridge & crest of nose: infratrochlear and external nasal branches of the ophthalmic nerve
side of nose: infraorbital branch of the maxillary nerve
vestibule of nose
area of nasal cavity lying just inside the nostril
atrium
entrance to the middle meatus and it sits superior to the vestibule
roof of nasal cavity
anteriorly by: nasal and frontal bones
middle by: cribriform plate of the ethmoid
posteriorly by: sphenoid
floor of nasal cavity
it is the superior surface of the hard palate. components include:
palatine process of maxilla
horizontal plate of palatine bone
lateral wall of nasal cavity
-it has three projections of bone: superior conchae middle conchae (parts of ethmoid bone) and inferior conchae
sphenoethmoidal recess
small area above the superior concha. it receives the opening of the sphenoid air sinus
superior meatus
- lies below superior concha
- it receives the openings of the posterior ethmoid sinuses
middle meatus
- it lies below the middle concha
- it has a rounded swelling: bulla ethmoidalis that is formed by middle ethnoidal air sinuses, a curved opening hiatus semilunaris lies below the bulla
- the end of the hiatus leads to a channel called infundibulum which leads to frontal sinus
- maxillary sinus opens into the middle meatus through hiatus semilunaris
inferior meatus
- lies below the inferior concha
- receives opening of the lower end of the nasolacrimal duct
medial wall of nasal cavity
it is former by the nasal septum
upper portion by: verticular plate of ethmoid
lower portion by: vomer
anterior part by: septal cartilage
olfactory area
it includes roof of nasal cavity, sphenoethmoidal recess, superior surface of superior concha, superior edge of the nasal septum
nasal cavity nerve supply
olfactory nerves
for general sensation: branches of ophthalmic division and maxillary division of the trigerminal nerve
nasal cavity blood supply
-branches of maxillary artery
most important branch is the sphenopalatine artery, which anatomoses with the septal branch of the superior labial branch of the facial artery
nasal cavity lymph drainage
from the vestibule: submandibular nodes
remainder to: upper deep cervical nodes
epistaxis
- chronic profuse bleeding from nose
- causes: nose picking, degeneration of the nasal septum resulting from chronis use of cocaine
- most episodes occur on the anteroinferior portion of the septum and involve septal branches of the sphenopalatine and facial vessels
transnasal surgery
- it is done to approach the pituitary gland
- instruments run across the nasal cavity to its posterior roof, sphenoid is pierced, sphenoid air sinus is traverses and sella turcica is entered from below
function of paranasal sinuses
- reduce the weight of the skull
- give resonance to voice
- drainage of mucus by siphon action
maxillary sinus
- pyramidal in shape
- floor of the orbit forms the roof
- drains into middle meatus through hiatus semilunaris
frontal sinuses
- roughly triangular
- drains into middle meatus through infundibulum
sphenoid sinuses
- lie within the body of sphenoid
- drains into sphenoethmoidal recess
ethmoid sinuses
-three pairs are present between the nose and the orbit
anterior group: drains into infundibulum & middle meatus
middle group: drains into middle meatus on bulla ethmoidalis
posterior group: drains into superior meatus
which sinus is most prone to infection?
maxillary sinus
