Sinus Positioning Flashcards
What’s another name for the PA sinus view?
Modified Caldwell method
What another name for the modified Caldwell method?
PA sinus
What IR is used for sinus views?
10x12
What breathing technique are sinus views taken on?
Suspended respiration
What SID is used for sinus views?
40”
What structures are seen for a PA sinus view (modified caldwell)?
- Demonstrates the frontal sinuses and anterior ethmoidal air cells
- Symmetric petrous ridges, lying in lower thrid of orbits
Where is the CR for a PA sinus view (modified caldwell)?
Exits at the nasion
How is the patient positioned for a PA sinus view (modified caldwell)?
Upright PA with nose resting on grid
Where is the MSP for a PA sinus view (modified caldwell)?
Perpendicular to IR
Where is the OML for a PA sinus view (modified caldwell)?
At 15 degrees with the CR
When doing a PA sinus view (modified caldwell), what improves the detail of air/fluid levels?
A horizontal CR
Why would you use a horizontal CR for a PA sinus view (modified caldwell)?
To improve detail of air/fluid levels
What is another name for a parietoacanthial sinus?
Waters method
What is another name for the waters method?
Parietoacanthial sinus
What structures are seen for the Parietoacanthial sinus (waters method)?
- Demonstrates the maxillary sinuses best
- Distance between the lateral border of skull and orbit of skull and orbit equal on each side
- Petrous ridges below maxillary sinuses
- Open mouth= Sphenoidal sinuses projected through the open mouth
Where is the CR for a Parietoacanthial sinus (waters method)?
Exits the acanthion
How is the patient positioned for a Parietoacanthial sinus (waters method)?
Patient is upright PA with the chin on the bucky/table and the nose is 3/4” from the bucky/table
Where is the MSP for the Parietoacanthial sinus (waters method)?
Perpendicular to IR
Where is the OML for the Parietoacanthial sinus (waters method)?
37 degrees with plane of IR
Where is the MML for the Parietoacanthial sinus (waters method)?
Approx. perpendicular to the plane of the IR
In what case will the MML not be perpendicular to the IR for a Parietoacanthial sinus (waters method)?
When doing the open mouth waters method
What does the patient do for an open-mouth waters method?
The patient is instructed to open their mouth
What are the structures seen for a lateral sinus (most affected side only)?
- Demonstrates all sinus groups
- No rotation of sella turcica
- Superimposed orbital roofs and mandibular rami
Where is the CR for the lateral sinus (most affected side only)?
1/2” to 1” posterior to outer canthus
How is the patient positioned for a lateral sinus (most affected side only)?
Patient is upright in a RAO/LAO position with head in true lateral position
Where is the MSP for a lateral sinus (most affected side only)?
Parallel to IR
Where is the IP line for a lateral sinus (most affected side only)?
Perpendicular to IR
Where is the IOML for a lateral sinus (most affected side only)?
Perpendicular to the front edge of the IR
What are the structures seen in a Submentovertical sinus (SMV)?
- Demonstrates the sphenoid and ethmoid sinuses
- Anterior frontal bone superimposed by mental protuberance (chin)
- Mandibular condyles anterior to petrous pyramids
- No rotation of the head
Where is the CR for a Submentovertical sinus (SMV)?
Perpendicular to IOML, entering at MSP and 3/4” anterior to the level of the EAM
Where is the MSP for a Submentovertical sinus (SMV)?
Perpendicular to IR
How is the patient positioned for a Submentovertical sinus (SMV)?
Patient is upright with head tilted back (vertex on upright bucky)
Where is the IOML for a Submentovertical sinus (SMV)?
Parallel with IR
What might you have to do to the CR that it enters perpendicular to the IOML?
Angle it
Why would you have to angle the CR for a Submentovertical sinus (SMV)?
So that it enters perpendicular to the IOML
