ARRT Head and Neck Procedures 3

Question 1

Which projection best demonstrates the mandibular condyles in the axiolateral oblique position?

Accepted Answer

Towne projection

Answer

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?

Accepted Answer

1 inch anterior and 1 inch superior to the EAM

Answer

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?

Accepted Answer

Foramen magnum

Answer

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?

Accepted Answer

15° medially

Answer

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?

Accepted Answer

Sphenoid sinuses

Answer

The open-mouth Waters view projects the sphenoid sinuses through the open mouth, making them visible without overlying structures.

ARRT - American Registry of Radiologic Technologists Practice Test