ARRT Head and Neck Procedures 3 — Questions and Answers
Question 1: Which projection best demonstrates the mandibular condyles in the axiolateral oblique position?
- Towne projection (Correct answer)
- Waters projection
- PA Caldwell
- Lateral skull
Correct answer: Towne projection
The Towne (AP axial) projection with additional modifications demonstrates the mandibular condyles by projecting them below the mastoid processes.
Question 2: When positioning for a lateral projection of the sella turcica, the central ray enters at which landmark?
- 1 inch anterior and 1 inch superior to the EAM (Correct answer)
- Glabella
- Nasion
- Vertex of the skull
Correct answer: 1 inch anterior and 1 inch superior to the EAM
For a lateral sella turcica, the CR enters approximately 3/4 inch anterior and 3/4 inch superior to the external auditory meatus (EAM).
Question 3: On the AP axial (Towne) projection, the dorsum sellae and posterior clinoid processes are projected into which structure?
- Foramen magnum (Correct answer)
- Orbital plates
- Petrous ridges
- Sphenoid sinuses
Correct answer: Foramen magnum
The Towne projection projects the dorsum sellae and posterior clinoid processes through the foramen magnum.
Question 4: For a radiograph of the zygomatic arch using the oblique inferosuperior projection, the CR is directed at what angle?
- 15° medially (Correct answer)
- 30° caudally
- 45° cephalically
- Perpendicular
Correct answer: 15° medially
For the oblique inferosuperior (tangential) zygomatic arch projection, the CR is angled approximately 15° medially and 15° cephalically.
Question 5: Which structure is best seen on the open-mouth Waters view of the face?
- Sphenoid sinuses (Correct answer)
- Frontal sinuses
- Ethmoid sinuses
- Mastoid air cells
Correct answer: Sphenoid sinuses
The open-mouth Waters view projects the sphenoid sinuses through the open mouth, making them visible without overlying structures.
Question 6: On a properly positioned lateral skull radiograph, the sella turcica should appear how?
- As a single image without superimposition (Correct answer)
- Double-contoured due to bilateral visualization
- Projected above the petrous ridges
- Not visible
Correct answer: As a single image without superimposition
A properly positioned lateral skull shows the sella turcica as a single, non-double-contoured image, indicating true lateral positioning.
Question 7: For an AP projection of the cervical spine, the CR is angled how to open the intervertebral disk spaces?
- 15–20° cephalad (Correct answer)
- 10° caudad
- Perpendicular
- 30° cephalad
Correct answer: 15–20° cephalad
For AP cervical spine, the CR is angled 15–20° cephalad to open the intervertebral disk spaces and reduce the lordotic curve.
ARRT Head and Neck Procedures 3
Which projection best demonstrates the mandibular condyles in the axiolateral oblique position?