LRA-225 Week 3 notes Flashcards
define paranasal sinuses
- large air-filled cavities
- also called accessory nasal sinus (due to being lined with mucous membranes)
what are the 4 groups of paranasal sinuses?
- frontal
- maxillary
- sphenoid
- ethmoid
who do the paranasal sinuses communicate with?
- sinuses communicate with each other
- communicate with the nasal cavity
how many sinuses are in the maxillary bones?
2
how many sinuses are in the frontal bone?
2
how many sinuses are in the ethmoid bone?
several
how many sinuses are in the sphenoid bone?
1 or 2
which sinuses are only part of the facial bone structures?
maxillary sinuses
which sinuses are contained in their respective cranial bones?
- frontal
- ethmoid
- sphenoid
what is the purpose of the paranasal sinus?
- vocal resonance
- lighten the weight of the skull
- produce mucous (to moisten the nasal passageways and air entering the nasal airway)
which paranasal sinus is developed, or shown, at birth?
maxillary sinuses
which paranasal sinuses are developed at ages 6-7?
- frontal and sphenoid sinuses
which paranasal sinus is developed last?
ethmoid sinus
which is the largest paranasal sinus?
maxillary sinus
what is another name for the maxillary sinus?
- antrum
- antrum of highmore
what is the shape of the maxillary sinus?
- pyramid (frontal view)
- cube (lateral view)
what are the dimensions of the maxillary sinuses?
- vertical: 1-1 1/2 inches
- 1 inch
what is the site of communication of the maxillary sinus?
- opening into the middle nasal meatus
- located at the superior medial aspect of the sinus cavity
why is erect preferred when positioning for a sinus view?
When a person is erect, any mucus or fluid trapped within the sinus tends to remain there and layer out, forming an air-fluid level
where is the frontal sinus located?
between the inner and outer tables of the skull, posterior to the glabella
true or false: frontal sinuses are rarely symmetric
true
what separates the frontal sinuses?
- nasal septum??
are frontal sinuses larger in men or women?
men
where are the ethmoid sinuses located?
within the lateral masses or labyrinths of the ethmoid bone
how does the ethmoid sinuses look when in a lateral view?
appear to fill in the orbits
where are the sphenoid sinuses located?
lie in the body of the sphenoid bone directly below the sella turcica
what is the shape of the sphenoid body?
cubic, divided by a thin septum to form two cavities
true or false: Because the sphenoid sinuses are so close to the base or floor of the cranium, sometimes pathologic processes make their presence known by their effect on these sinuses
true
define sphenoid effusion
a basal skull fracture and that either blood or cerebrospinal fluid is leaking through the fracture into the sphenoid sinuses
what sinuses make up the osteomeatal complex?
- frontal
- maxillary
- ethmoid
define sinusitis
an infection of either the frontal, maxillary, or ethmoid sinus
what are the 2 key passages?
infundibulum and middle nasal meatus