facial bones, orbits, sinuses, nasal bones Flashcards
where is CP for lat facial bones
at zygoma, 1/2 between tip of the nose and EAM
why would you do lateral facial bones erect
air-fluid levels shown
easier for hypersthenic pts
what is the projection for a waters method
parietoacanthial
what should be perp to bucky up on a waters
MML perp to IR
on a waters, what angle should the OML be form the IR
37 degrees
what should facial waters collimation include
zygomatic arches
include orbits and mandible
what is the CR used for a facial caldwell
15 deg caudad
where should the petrous ridges be on a facial caldwell
in bottom 1/3 of orbits
what MUST happen if there is suspected foreign body in the orbits
wipe down bucky, grid, and IR
eyes must focus on one point, to hold still
what are the 3 types of orbital fractures
blowout
tripod
le forte
what is a blowout fracture
frontal pressure fractures the orbital floor
what is a tripod fracture
3 separate fractures, all around the zygoma
what is a le forte fracture
specific fracture patterns
3 tyoes
which le forte is this
I
which le forte is this
II
which le forte is this
III
what are the 2 routine orbits views
modified caldwell (30)
OR modified waters (55)
and lateral IOML
where is the CP of a lateral orbit
outer canthus of remote eye
for orbits, which side goes against the IR
the affected side
what is the CR for an orbits modified Caldwell
30 deg caudad
where are the petrous ridges on an orbits modified caldwell
below the orbital margins
what CR is used for the shallow waters
OML 50-55 dge from bucky
where is the CP for a shallow waters
outer canthus of orbits
where are the petrous ridges on a shallow waters
in lower 1/3 of maxillary sinuses
what is the shallow waters especially good for
visualizing blowouts fractures
what are the essential sinus projections
- lateral
- Caldwell - PA axial
- open mouth waters - parietoacanthial
- SMV - suubmentovertical
what needs to happen for sinus imaging
clean the IR prior
done UPRIGHT (fluid levels)
where is the CP on a lateral sinuses
1/2 to 1” posterior to outer canthus
where is collimation on lateral sinuses
down to mouth, back to EAM
the sinus lateral projection is best for which sinus
sphenoid sinuses
how is the sinus Caldwell lined up
OML 15 deg to IR
line from TEA to bottom 1/3 of orbit
what does the CR do in sinus studies
ALWAYS STAYS HORIZONTAL
what sinuses are best deomnstrated on a Caldwell methid
frontal sinuses
anterior ethmoid cells
what angle is used for an open mouth waters
OML at 37 degrees
what sinus is best demonstrated in open mouth waters
sphenoid through mouth
maxillary sinuses
where is the CP on a sinus SMV
midway between tip of nose and EAM
what sinuses does the SMV best demonstrate
sphenoid and ethmoid sinuses
what are the routine nasal views
lateral
parietoacanthial
what is different about nasal images
non grid, bilateral!!
where is the CP on lateral nasal bones
1/2 inch inferior to nasion
what is the collimation for a waters nasal bones
length and width of nasal septum, AND maxillary sinuses
