RAD 245- Open Mouth- AP Cervical Atlas and Axis Projection- Chapter 8- Module 3

Question 1

What is the CR angulation on the open mouth projection?

Answer 1

CR 5 degrees cephalically

Question 2

What is the positioning error when the ATLAS pivots around the dens so that the lateral mass located on the side for which the face is turned is displaced ANTERIORLY and the mass located on the side TOWARD which the face is turned is displaced POSTERIORLY?

Answer 2

Head Rotation

Question 3

What is the positioning error when the space between the lateral mass and dens to narrow on the side from which the face if turned and to enlarge on the side toward which the face is turned?

Answer 3

Rotation (Basically, the space is open on the side in which the face is turned)

Dens also moves away from the side which the face is rotated towards

Spinous process also moves opposite from which the side it is rotated

Question 4

What is the positioning error when the occiput is positioned accurately superior to the dens, but the atlantoaxial joint is closed and the upper incisors are positioned too superiorly?

This positioning will also demonstrate the spinous process of the axis at the level of the 3rd vertebral body

Answer 4

The C-spine was extended (backwards) OR

The CR was angled too cephalically

Question 5

What type of angle do you use on a trauma patient who cannot move their neck?

Answer 5

10 degree Caudal Angle at the MSP at the level 0.5 inferior to the lower surface of the incisors

Question 6

For a trauma patient, What is the positioning error that causes the upper incisors to be demonstrated superior to the dens and the dens to be superimposed over the occipital base?

Answer 6

Insufficient Caudal Angulation

Question 7

For the trauma patient, What is the positioning error when the occipital base is demonstrated SUPERIOR to the dens and the upper incisors are superimposed over the dens?

Answer 7

CR was Angled TOO Caudally