Ch. 11 Mandible, TMJ, and Sinuses Workbook

Question 1

what is the older term for the maxillary sinuses

Answer 1

antrum/antrum of Highmore

Question 2

an infection of the teeth may travel upward and involve what sinus

Answer 2

maxillary sinus

Question 3

specifically, where are the frontal sinuses located

Answer 3

between inner and outer tables of the skull, posterior to the glabella

Question 4

the frontal sinuses rarely become aerated before what age

Answer 4

6 years

Question 5

which specific aspect of the ethmoid bone contains the ethmoid sinuses

Answer 5

lateral masses or labyrinth

Question 6

what is the drainage pathway for the paranasal sinuses called

Answer 6

osteomeatal complex

Question 7

which sinus is projected through the open mouth with a PA axial transoral projection

Answer 7

sphenoid sinus

Question 8

what is the name of the passageway between the maxillary sinuses and the middle nasal meatus

Answer 8

infundibulum

Question 9

T/F - most CT studies of the paranasal sinuses do not require the use of contrast media

Answer 9

true

Question 10

what position is most often used when performing a CT study of the sinuses

Answer 10

prone

Question 11

T/F - the PA axial projection of the mandible produces an elongated view of the condyloid processes

Answer 11

true

Question 12

which projection of the mandible projects the opposite half of the mandible away from the side of interest

Answer 12

axiolateral oblique

Question 13

what must be done to prevent the ramus of the mandible from being superimposed over the c-spine with an axiolateral oblique projection of the mandible

Answer 13

extend the chin

Question 14

how much skull rotation (from the lateral skull position) toward the IR is required with an axiolateral oblique projection for demonstrating the body of the mandible

Answer 14

30 degrees

Question 15

how much skull rotation (from the lateral skull position) toward the IR is required with an axiolateral oblique projection for demonstrating the mentum region

Answer 15

45 degrees

Question 16

how much skull rotation (from the lateral skull position) toward the IR is required with an axiolateral oblique projection for demonstrating the ramus region

Answer 16

0 degrees (true lateral)

Question 17

how much skull rotation (from the lateral skull position) toward the IR is required with an axiolateral oblique projection for demonstrating a general survey of the mandible

Answer 17

10-15 degrees

Question 18

what is the max CR angle needed for all of the axiolateral oblique projections

Answer 18

25 degrees cephalad

Question 19

what specific positioning error has been committed if both sides of the mandible are superimposed with an axiolateral oblique projection

Answer 19

insufficient cephalic CR angle or skull tilt

Question 20

where should the CR exit for a PA axial projection of the mandible

Answer 20

acanthion (at lips for PA projection)

Question 21

which cranial positioning line is places perp to the IR for a PA or PA axial projection of the mandible

Answer 21

orbitomeatal line (OML)

Question 22

T/F - for a true PA projection of the mandibular body (if this is the area of interest) the AML should be perp to the IR

Answer 22

true

Question 23

T/F - the CR should be angled 20-25 degrees caudad for the PA axial projection of the mandible

Answer 23

false - cephalad

Question 24

which aspect of the mandible is best visualized with an AP axial projection

Answer 24

condyloid process

Question 25

what CR angle is required for the AP axial projection of the mandible if the OML is perp to the IR

Answer 25

35 degrees caudad

Question 26

what CR angle is required for the AP axial projection of the mandible if the IOML is perp to the IR

Answer 26

42 degrees caudad

Question 27

where is the CR centered for an AP axial projection of the mandible

Answer 27

1" superior to glabella

Question 28

which projection of the mandible demonstrates the entire mandible, including the coronoid and condyloid processes

Answer 28

SMV projection

Question 29

which imaging system provides a single, frontal perspective of the entire mandible

Answer 29

orthopantomography (panoramic tomography)

Question 30

what device provides inherent collimation during an orthopantomographic procedure

Answer 30

narrow, vertical slit diaphragm

Question 31

which cranial line is places parallel to the floor for orthopantomography of the mandible

Answer 31

infraorbitomeatal line (IOML)

Question 32

what type of IR must be used with digital orthopantomography

Answer 32

digital detector or photostimulable phosphor plate

Question 33

T/F - the modified Law method provides a bilateral and functional study of the TMJ

Answer 33

true

Question 34

T/F - the mandibular condyles move anteriorly as the mouth is opened

Answer 34

true

Question 35

which projection/method of the TMJ requires that the skull be kept in a true lateral position

Answer 35

Schuller

Question 36

the axiolateral (Schuller method) projection for the TMJ requires a CR angle of what

Answer 36

25-30 degrees caudad

Question 37

the axiolateral oblique projection of the TMJ is commonly referred to as what

Answer 37

modified Law

Question 38

the axiolateral oblique projection of the TMJ requires how much head rotation from lateral

Answer 38

15 degrees

Question 39

the axiolateral oblique projection of the TMJ requires what CR angle

Answer 39

15 degrees caudad

Question 40

if the area of interest is the temporomandibular fossae, what should the angle of the CR to the OML be for the AP axial (modified Towne) projection to reduce superimposition of the temporomandibular fossae and mastoid portions of the temporal bone

Answer 40

40 degrees caudad

Question 41

aligning what plane perp to the IR prevents rotation of either a PA or an AP axial mandible

Answer 41

midsagittal

Question 42

what kVp range should be used for paranasal sinus radiography

Answer 42

75-85 kVp

Question 43

to demonstrate any possible air or fluid levels within the paranasal sinuses, it is important to do these two things

Answer 43

- perform positions erect when possible - use horizontal x-ray beam

Question 44

T/F - ultrasound exams of the maxillary sinuses to rule out sinusitis are possible

Answer 44

true

Question 45

T/F - MRI is the preferred modality to study soft tissue changes and masses within the paranasal sinuses

Answer 45

true

Question 46

T/F - secondary osteomyelitis is often caused by tumor invasion

Answer 46

false

Question 47

list the 4 most commonly performed routine projections for paranasal sinuses

Answer 47

- lateral - PA caldwell - parietoacanthial (waters) - SMV

Question 48

which single projection for a paranasal sinus routine provides an image of all 4 sinus groups

Answer 48

lateral

Question 49

if the patient cannot stand for the lateral projection of the paranasal sinuses, the projection should be taken how

Answer 49

with a horizontal x-ray beam

Question 50

which paranasal sinuses are best demonstrated with a PA (caldwell) projection

Answer 50

frontal and anterior ethmoid

Question 51

to avoid angling the CR for the erect PA (axial) caldwell sinus projection, the head should be adjusted so that the OML is how many degrees from horizontal

Answer 51

15 degrees

Question 52

which group of paranasal sinuses is best demonstrated with a parietoacanthial (waters) projection

Answer 52

maxillary sinuses

Question 53

the OML forms what degree angle with the IR in the parietoacanthial (waters)

Answer 53

37 degrees

Question 54

which positioning line is placed perp to the IR for a parietoacanthial projection

Answer 54

mentomeatal line (MML)

Question 55

where are the petrous ridges on a well-positioned parietoacanthial projection

Answer 55

just below the maxillary sinuses

Question 56

which paranasal sinuses are demonstrated with an SMV projection of the paranasal sinuses

Answer 56

sphenoid, ethmoid, and maxillary sinusesj

Question 57

where should the CR exit for both the PA parietoacanthial (waters) and PA transoral (open-mouth waters) projections

Answer 57

level of the acanthion

Question 58

what is the one major difference in positioning between parietoacanthial and PA axial transoral projections

Answer 58

mouth is open with PA transoral

Question 59

which paranasal sinuses are projected through the oral cavity with the PA axial transoral projection

Answer 59

sphenoid sinuses

Question 60

which projection shows the sphenoid sinus in oral cavity

Answer 60

PA transoral

Question 61

which projection shows an inferosuperior view of sphenoid and ethmoid sinus

Answer 61

SMV for sinuses

Question 62

which projection shows all 4 paranasal sinuses demonstrated

Answer 62

lateral

Question 63

which projection shows the best view of maxillary sinus

Answer 63

parietoacanthial

Question 64

which projection shows the best view of frontal and ethmoid sinuses

Answer 64

PA (axial) caldwell

Question 65

a radiograph of a PA (caldwell) projection for paranasal sinuses shows the petrous ridges are projected into the lower half of the orbits and are obscuring the ethmoid sinuses. the tech used a horizontal x-ray beam for the projection. the skull was positioned to place OML at a 15 degree angle from horizontal plane. what positioning modification is needed

Answer 65

head and neck need to be extended more to project petrous ridges below ethmoid sinuses

Question 66

a radiograph of a PA transoral projection shows the sphenoid sinus is superimposed over the upper teeth and the nasal cavity. how must the position be modified to avoid this problem during repeat

Answer 66

increase extension of head and neck to project entire sphenoid sinus through oral cavity

Question 67

a radiograph of an axiolateral oblique projection of the mandible shows the bod of the mandible is severely foreshortened. the body of the mandible is the area of interest. what positioning error lead to this outcome

Answer 67

insufficient rotation of the skull toward the IR, skull should be rotated 30 degrees (from lateral position) toward the IR to prevent foreshortening of the body

Question 68

a patient comes to the radiology dept. to rule out a possible polyp within the sphenoid sinus. what routine and/or special projection provides the best overall assessment of the paranasal sinuses for this patient

Answer 68

PA transoral special projection in addition to routine 4 sinuses projections (PA caldwell, lateral, parietoacanthial, SMV)