Protocols
These projections/positions are used during a trauma skull protocol.
AP Townes, AP or PA Caldwell, 2 lateral images (either X-table or upright)
Angle for an AP Townes during a skull series when the OML is perpendicular to the IR. (When the IOML is perpendicular?)
30° for OML. 37° for IOML Caudad
How would you fix this PA Caldwell image (used for skull series) What technique would be used?
75 kVp @ 12.5 mAs
Centering point for an AP Townes for a skull exam.
6.5cm above the glabella
The acronym for this positioning point: EAM
External Auditory Meatus
These projections/positions are required for sinus imaging.
PA Caldwell, Parietoacanthial Waters, Lateral (affected side closest to IR)
Angle for an AP Caldwell during a trauma facial bones series when the OML is perpendicular to the IR.
15° cephalad.
How would you fix this Parietoacanthial Waters image (used for sinuses)? What technique would use?
Turn head left (patient is rotated to the right).
75 kVp @ 10 mAs
The beam exits this positioning point in a PA Caldwell for facial bones.
The Nasion
The acronyms for these skull positioning lines: OML/IOML.
Orbitomeatal line/ Infraorbital meatal line
In this modified version of the Waters position the LML is perpendicular to the IR, and the OML is 55° to the IR.
Waters position used for orbits.
Angle for Modified AP Townes for a mandible series when the OML is perpendicular to the IR (When the IOML is perpendicular?)
35° OML, 42° IOML caudad.
How would you fix this AP Townes image (used for skull series)? What technique would you use?
Tuck chin or angle more. (Dorsum sellae is superior to the foramen magnum)
75 kVp @ 16mAs
Centering point for a lateral skull.
5cm superior to the EAM
The acronym for this positioning line: MML.
Mentomeatal line
These projections/positions are used for mandible imaging.
AP Modified Townes, PA or PA Modified Caldwell, Axiolateral (oblique)
Angle used for TMJ's in an axiolateral when the head is in a true lateral.
25-30° caudad
Does this lateral skull show tilt or rotation (or both)? What technique would you use?
Rotation
70 kVp @ 10 mAs
The beam exits this centering point in a Waters position for sinuses.
Acanthion
Acanthiomeatal line
These projections/positions are used for imaging zygomatic arches.
AP Modified Townes, Submentovertex (SMV), Oblique Inferosuperior (tangential)
Angle used for a modified PA Caldwell when performing orbit imaging (OML is perpendicular to the IR).
30° caudad
This image is a part of what series? What is the position/projection?
AP Modified Townes for mandible.
These are the positioning points for a TMJ exam, using the Schuller method (preferred method at QEH)
1.3cm anterior and 5cm superior to the upside EAM
The acronym for this positioning line: LML