Nasal Cavity And Paranasal Sinuses Flashcards
What supports the lower part of the nose?
What does it consist of?
Cartilaginous framework
One septal and two major alar cartilages
What makes up the upper part of the nose?
Bony framework, nasal bones and frontal processses of maxillae
Cartilages are connected to each other and to bones by
Fibrous tissue
Forms anterior part of nose, has 2 lateral processes (triangular in shape, located below inferior border of nasal bones)
Septal cartilage
U-shaped, form lateral and medial borders of nostrils (lateral and medial curry, respectively)
Major alar cartilages
Chamber consisting of bony and cartilaginous walls, covered with mucosa
Nasal cavity
Nasal cavity opens anteriorly on face via..
Nares
Nasal cavity communicated posteriorly with pharynx via
Posterior nasal apertures (choanae)
Area immediately above nares, lines with skin and stiff hairs
Vestibule
Function of the nasal cavity
Olfaction, conditioning of inspired air (filtration, humidification, warming), and reception of secretions from paranasal air sinuses and nasolacrimal duct
Part of nasal cavity located above and behind superior nasal concha
Sphenoethmoidal recess
Composition of floor of Nasal Cavity
Hard palate
Composition of roof of bony walls
Anterior to posterior..
Nasal bone, nasal spine of frontal bone, cribriform plate of ethmoid, anterior and inferior aspects of body of sphenoid
Medial walls of nasal cavity
Nasal septum
Perpendicular plate of ethmoid and vomer (+ smaller contributions from sphenoid, maxilla, and palatine)
Lateral wall of nasal cavity
Maxilla, lacrimal bone, inferior nasal concha, ethmoidal labyrinth, perpendicular plate of palatine, and medial pterygoid plate
Has 3 scroll like bony projections (nasal conchae) with space in between (meatus)
Communications of superior meatus
Posterior ethmoidal air cells open via small orifices in its lateral wall
Communications of middle meatus
Ethmoidal bulla: openings of middle ethmoidal air cells
Semilunar hiatus, inferior to ethmoidal bulla
Optimum of maxillary sinus located in lower part of semilunar hiatus
- Elevation in lateral wall of middle meatus cause by middle ethmoidal air cells.
- Curved cleft Structure located inferior and anterior to 1
Ethmoidal bulla
Semilunar hiatus
What is located in lower part of semilunar hiatus?
Optimum of maxillary sinus
Communications of middle meatus
Superior end of semilunar hiatus leads into a curved channel known as the infundibulum
Receives openings of anterior ethmoidal air cells, but in some individuals it also receives opening of frontal sinus
And in others, it has a superior blind end, and frontal sinus opens directly into Anterior part of middle nasal meatus
Infundibulum
Communications of inferior meatus
Opening of nasolacrimal duct is located in anterior part of its lateral wall
Communications of sphenoethmoidal recess
Opening of sphenoidal sinus
Lines entire nasal cavity, except vestibule
Firmly bound to periosteum and perichrondium of supporting structures
Continuous with mucosal lining of nasopharynx, paranasal air sinuses, and nasolacrimal duct
Nasal mucosa
Types of nasal mucosa
Olfactory mucosa
Respiratory mucosa
Lines highest part of roof and adjacent parts of septum and lateral wall, contains olfactory receptor cells
Olfactory mucosa
Lines rest of nasal cavity (respiratory epithelium–ciliated, psuedostratified, columnar epithelium)
Respiratory epithelium
General sensory nerve supply in nasal cavity
Derived from branches of ophthalmic and maxillary nerves
Anterior ethmoidal nerve, nasal branches of infraorbital nerve, nasal branch of anterior superior alveolar nerve, posterolateral nasal branches, nasopalatine nerve
Branch of nasociliary nerve (from opthalmic nerve)
Passes from orbit to anterior cranial fossa via anterior ethmoidal foramen
Runs forward on cribriform plate
Leaves anterior cranial fossa and enters nasal cavity via small slit at side of crista Galli
Anterior ethmoidal nerve
Anterior ethmoidal nerve branches
Internal nasal branches