RAD 245- C-Spine PA or AP Axial Oblique Projection- Chapter 8- Module 3

Question 1

What is positioned parallel to the floor?

Answer 1

IPL parallel to the floor

Question 2

What is the patient angle?

Answer 2

45 degrees from the IR

Question 3

Where is the CR centered?

Answer 3

CR to MSP, halfway between the EAM and the jugular notch

Question 4

How is the CR angled in a PA axial oblique projection?

Answer 4

CR 15 to 20 degrees Caudally

Question 5

How is the CR angled in a AP axial oblique projection?

Answer 5

CR 15 to 20 degrees Cephalically

Question 6

What is the positioning error when the intervertebral foramina are narrowed or obscured and the pedicles of interest are foreshortened?

Answer 6

If the cervical vertebral rotation is LESS than 45 degrees

Question 7

What is the positioning error when the pedicles of interest are partially foreshortened and the opposite pedicles are aligned with the midline of the vertebral bodies, and the zygapophyseal joints that are demonstrated without vertebral body superimposition are demonstrated in profile?

Answer 7

If the cervical vertebrae are rotated MORE than 45 degrees

Question 8

What is a larger degree of angulation used for patients with?

Answer 8

Higher degrees of lordotic cervical curvature

Question 9

What is the positioning error when the disk spaces are obscured and the cervical bodies are NOT seen as distinct individual structures?

Answer 9

The C-spine vertebral column is tilted

OR

The CR is inaccurately angled with the intervertebral disk spaces

Question 10

What causes upper cervical vertebral column tilting?

Answer 10

Caused by the head being positioned TOO close to or far away from the IR (Poor IPL posiitoning)

Question 11

What causes lower cervical vertebrae tilting?

Answer 11

Caused by the upper thorax being tilted anteriorly

Question 12

What is the positioning error when the PA axial oblique projection when the intervertebral disk spaces are closed, the cervical bodies are distorted, and zygapophyseal joint spaces are demonstrated?

Answer 12

The cervical vertebral column tilted anteriorly (vertebrae leaning toward the IR)

OR

The CR angled too cephalically to align with the intervertebral disk spaces

Question 13

What is the positioning error when the transverse process is seen within the intervertebral formamen?

This can happen on a PA or AP Axial Oblique Projections

Answer 13

More tilting

OR an

Increase in cephalic CR angulation

Question 14

What type of patient has the lower cervical vertebrae angled toward the IR because of the greater lordotic curvature of the area?

Answer 14

A patient with severe kyphosis

Question 15

What type of angle is needed for the kyphotic patient?

Answer 15

CR needs to be angled more than the suggested 15-20 degrees for the oblique projections

Question 16

What projection, AP Axial or PA Axial, is the cranial cortex and mandibular rami situated farther from the IR projected superiorly?

Answer 16

AP Axial Oblique Projection

Question 17

On what projection, AP Axial or PA Axial, is the cranial cortex and mandibular rami situated farther from the IR projected inferiorly?

Answer 17

PA Axial Oblique Projection

Question 18

What needs to be done to avoid head and upper cervical column tilting?

Answer 18

Position the IPL parallel with the floor

Question 19

For the PA Axial oblique projection, the distances between the inferior cranial cortices and the inferior mandibular rami are INCREASED and the atlas’s vertebral foramen are OPEN?

Answer 19

The head and upper cervical vertebrae are tilted away from the IR

Question 20

For the PA Axial oblique projection, the distances between the inferior cranial cortices and the inferior mandibular rami are DECREASED and the atlas’s vertebral foramen are NOT demonstrated?

Answer 20

The head and upper cervical vertebrae were tilted toward the IR

Question 21

For the AP Axial Oblique projection, the distances between the inferior cranial cortices and the inferior mandibular rami are INCREASED and the atlas’s vertebral foramen are NOT demonstrated?

Answer 21

The head and upper cervical vertebrae are tilted AWAY from the IR

Question 22

For the AP Axial oblique projection, the distances between the inferior cranial cortices and the inferior mandibular rami are DECREASED and the atlas’s vertebral foramen are Demonstrated?

Answer 22

The head and upper cervical vertebrae are tilted toward the IR

Question 23

For head positioning on an oblique projection, what is the positioning error when the mandibular rami are superimposed over C1 and C2?

Answer 23

The chin is NOT properly elevated

AND/OR

The patient’s head is rotated (From the lateral projection)

Question 24

For the Trauma patient and the oblique projections, WHAT is of interest when- The IR should be shifted to the left enough to align the left mastoid tip and the longitudinal axis of the IR and inferior enough position the right gonion with the transverse axis of the IR?

Answer 24

If the right vertebral foramina and pedicles are of interest

Question 25

For the Trauma patient and the oblique projections, WHAT is of interest when- The IR should be shifted to the right enough to align the right mastoid tip and the longitudinal axis of the IR and inferior enough position the left gonion with the transverse axis of the IR?

Answer 25

If the left vertebral foramina and pedicles are of interest