Skull Review (theory 3)

Question 1

What position will the patient be put in for PA projection of the MANDIBLE

Answer 1

forehead and nose against IR, MSP and OML perpendicular to IR
Seated upright or supine

Question 2

whats the central ray for PA mandible

Answer 2

perpendicular exiting the acanthion

Question 3

What will be seen for PA mandible?

Answer 3

• Mandibular Rami
• Mandibular body (with the middle superimposed on spine though)
• Medial/lateral displacement if fracture present on rami

Question 4

What position is patient in for PA axial mandible?

Answer 4

forehead and nose against IR, MSP and OML perpendicular to IR
Seated upright or supine

Question 5

What is the CR for PA axial mandible?

Answer 5

CR:
- 20-25 degrees ceph
- exitting the acanthion

Question 6

What is show on PA axial mandible?

Answer 6

• Mandibular Rami
• Mandibular body (with the middle superimposed on spine though)
• Medial/lateral displacement if fracture present on rami

Question 7

What position is patient in for axiolateral/axiolateral oblique of the mandible

Answer 7

IPL perpendicular to IR
mouth closed teeth together
head against IR

Question 8

How would you position pt head for axiolateral mandible for ramus?

Answer 8

Pt head in true lat

Question 9

How would you position pt head for axiolateral mandible for mandibular body?

Answer 9

Pt head rotated 30 degrees toward the IR

Question 10

How would you position pt head for axiolateral mandible for symphysis?

Answer 10

Pt head rotated 45 degrees toward the IR

Question 11

What is the CR for axiolateral oblique mandible?

Answer 11

25 degrees cephalad to pass directly through what you need (body, symph or rami)

Question 12

If the shoulder will project onto madible, what do?

Answer 12

• Adjust MSP of skull with ~15 degree with anterior part getting closer to IR
• adjust cephalic angle to 10 degrees cephalad

Question 13

what structure are seen for axiolateral mandible?

Answer 13

The body, symph, or rami that is parallel to the IR

Question 14

How to position patient for SMV?

Answer 14

hyperextend the neck so that IOML is as close to parallel with IR as possible no rotation, msp perpendicular to midline of IR

Question 15

whats the CR for SMV of zygomatic arches?

Answer 15

• Perpendicular to IOML and centered to zygomatic arches (~1” posterior to outer canthus)

Question 16

What is shown on SMV?

Answer 16

Bilateral symmetric images of the Z. arches without superimposition

Question 17

What is the patient position for tangential

Answer 17

IOML as parallel as possible to IR, rotate MSP of head 15 degrees towards side of interest, tilt head 15 degrees away from side of interest

Question 18

What is the CR for tangetial

Answer 18

CR perpendicular to IOML centered to Z. Arch 1” post outer canthus

Question 19

What is seen on tangetial?

Answer 19

Z. arch free of Superimposition
used in patients with depressed fracturs or flat cheekbones

Question 20

How to position for ap axial (modified townes) for Z. arches

Answer 20

MSP and OML perpendicular to IR with patient chin tucked so OML can do so.

Question 21

Whats the CR for modified townes?

Answer 21

Entering glabella ~1” above the nasion with 30 degrees caudad
If the patient cannot flex neck to get OML perpendicular, get IOML and adjust 30 to 37

Question 22

What is shown in modified townes?

Answer 22

Zygomatic arches free of superimposition

Question 23

How is patient positioned for AP axial TMJ?

Answer 23

MSP and OML perpendicular to IR

Question 24

CR for ap axial tmj?

Answer 24

35 degrees caudad, centered between TMJs and entering 3” above the nasion

Question 25

What projections are taken on AP axial TMJ?

Answer 25

Open and closed mouth

Question 26

If patient was in trauma recently, and required an AP axial TMJ what must NOT be done?

Answer 26

Dont do an open mouth AP axial as this could displace the fracture fragments

Question 27

How is the patient positioned for axiolateral TMJ?

Answer 27

Seated or prone, Head in lateral position with affected side closest to IR. MSP parallel, IPL perpendicular

Question 28

What is the CR for axiolateral TMJ?

Answer 28

@ midpoint of IR with 25-30 degree caudad angle entering 0.5" anterior and 2" superior to EAM (or center to the TMJ)

Question 29

What is seen on axiolateral TMJ?

Answer 29

TMJ anterior to EAM Condyle in mandibular fossa (closed mouth) Condyle inferior to articular tubercle (open mouth)

Question 30

During the parietoacanthial waters projection of the facial bones, what angle does the OML make with IR?

Answer 30

37 degrees

Question 31

If you can see the posterior arch of C1 on townes projection, what error happened?

Answer 31

Too much chin tuck

Question 32

What projections demonstrate bilaterally symmetric images of the zygomatic arches without superimposition?

Answer 32

SMV or modified townes (AP axial)

Question 33

What angle should OML make with modified waters of the orbits?

Answer 33

50 degrees

Question 34

Patient position for modified waters:

Answer 34

IR at the lvl of orbits Rest patient's chin on IR MSP perpendicular to IR OML makes 50 degree angle with IR