2b. Facial Bone Views and Positioning Flashcards
what is a zygomatico-maxillary fracture
in terms of what bones are separated from what, how many pieces of # there is, which 2 bones are fractured and where the breach is
zygoma separated from the frontal bone at zygomatico-frontal suture
comminuted fracture of zygomatic arch
orbital floor fracture
breach of lateral wall of maxillary antrum
what is a orbital blowout fracture
teardrop # of soft tissue has herniated from orbit into the maxillary antrum
what are the 3 views for facial bones
Occipitomental/OM - PA
occipitalmental30/OM30
lateral
what is the OM facial projection patient position
in terms of erect/supine, chin, what is perp to IR
patient erect, face against IR (can be supine if needed)
raise chin so OMBL is at 45*
MSP perp to IR
what is the central ray and centering point for OM facial view
Horizontal ray to root of nose/acanthion in midline
what is the exposure factor and SID for OM facial view
70kV, 20mAs
110cm SID
why is it better to do PA of facial bones rather than AP
better detail as PA face is closer to detector
PA has lower dosage to eyes
why is the erect better than supine for facial view OM
better air fluid demonstration
in the facial OM view are the petrous bones close to the orbitals
no they are very far away, lower than orbitals
what is the area of interest for a OM facial view
supraorbtial margins superiorly
zygomatic arches laterally
what is the patient positioning for the OM30 facial view
in terms of the patient erect/supine, face, chin, what is perp to IR
patient erect, face against IR
raise chin so RBL is at 45*
MSP perp to IR
what is the central ray for OM30 facial view
from horizontal CR angled 30* caudally
what is the centering point of OM30 facial view
center to point of chin (CR passes through zygomatic arches)
what is the exposure factors and SID for OM30 facial view
70kV, 25mAs, 110SID
what is the area of interest for OM30 facial view
lower orbital margin seen in profile
zygomatic arches demonstrated