Skull Prep Flashcards
GML stands for
Glabellomeatal line
OML stands for
Orbitomeatal line
IOML stands for
Infraorbitomeatal line
AML stands for
Acanthiomeatal line
LML stands for
Lips-meatal line
MML stands for
Mentomeatal line
CR angle for AP Axial Cranium (Towne Method)
30 degrees caudal to OML
- or -
37 degrees caudal to IOML
CR centering for AP Axial Cranium (Towne Method)
At MSP 2.5 inches above glabella
For the Towne Method, the ______ ______ should be symmetric
Petrous ridges
Correct CR angle and proper neck flexing in the Towne Method are indicated by _________
Dorsum sellae and posterior clinic processes visualized in the foremen magnum
Lateral cranium CR angle
Perpendicular
Positioning for Towne method
Depress chin, bringing OML perpendicular to the IR (if patient unable to flex, IOML perpendicular)
CR centering for Lateral Cranium
2 inches superior to EAM or halfway between glabella and inion for other types of skull morphologies
No tilt in a lateral cranium will be indicated by ______
Superimposed orbital plates (roof)
No rotation in a lateral cranium will be indicated by ______
Superimposition of greater wings of sphenoid and mandibular rami
Caldwell method positioning, facing (board/tube)
OML perpendicular to IR, facing board
The Towne Method is (a/an) ___ projection
The Caldwell Method is (a/an) ___ projection
AP axial, PA or PA axial
PA Caldwell CR angle and centering
Perpendicular, exit at glabella
PA Axial Caldwell CR angle and centering
15 caudad to OML, exit at nasion
What does SMV stand for?
Submentovertical
Patient position for SMV
hyperextend neck to get IOML parallel to IR, rest head on vertex
CR angle for SMV
Perpendicular to IOML
CR centering for SMV
1.5 inches inferior to mandible symphysis or midway between gonions (approx. 0.75 inches anterior to level of EAM)
Patient position for facial bones
Lateral side of head (side of interest) on IR
CR angle for facial bones
Perpendicular
CR centering for facial bones
Zygoma (prominence of cheek), midway between outer canthus and EAM
Patient positioning for Waters
Extend neck to get MML perpendicular to IR ~OR~ OML 37 degrees to IR
CR angle for Waters
Perpendicular
CR centering for Waters
Exit at acanthion
Patient positioning Modified Waters
OML 55 degrees to plane of IR/LML perpendicular to IR
CR angle Modified Waters
Perpendicular
CR centering Modified Waters
Exit at acanthion
What is the technical name for Waters/Modified Waters?
Parietoacanthial/Modified Parietoacanthial
IPL stands for
Interpupillary line
How would you do a reverse Waters (in a trauma scenario)?
-AP projection
-CR parallel to MML, centering at acanthion
How would you do a reverse Modified Waters (in a trauma scenario)?
-AP projection
-CR parallel to junction of LML centering at acanthion
Patient positioning for nasal bones
Head in true lateral position
CR angle for nasal bones
Perpendicular
CR centering for nasal bones
0.5” inferior to nasion
Patient positioning Bilateral SMV for Zygomatic Arches
extend neck to get IOML parallel to IR
CR angle for Bilateral SMV for Zygomatic Arches
Perpendicular to IOML (likely perpendicular to board)
CR centering for Bilateral SMV for Zygomatic Arches
~1.5 inches inferior to mandibular symphysis
The parieto-orbital oblique is also called ———-
Rhese Method
