FINAL RADIO

Question 1

Source to skin distance at 50kvp =

If >50kvp?

Answer 1

10cm

18cm

Question 2

Ideal paralleling technique distance

Answer 2

12 inches

Question 3

X ray field should have diameter of ___ or less

Answer 3

7cm

Question 4

If exposure is longer than __, operator should be able to terminate it

Answer 4

0.5s

Question 5

kvp and time need to be within __% accuracy

Answer 5

10%

Question 6

Coefficient of variation for reproductibility of kvp, timing, and radiation exposure shall not exceed ___ for 4 consecutive exposures

Answer 6

0.05

Question 7

Continuous dynamic process that can see things in real time

Answer 7

flouroscopy

Question 8

Hand-held radiation can only be used for intraoral (T/F)

Answer 8

TRUE

Question 9

If operating voltage (kVp) is from 50-70, total filtration is:
kvp in the 70s=
kvp in 80s=
kvp in 90s

Answer 9

50-70 = 1.5
70s= 2.1
80s=2.3
90s=2.5

Question 10

Which film speed is the minimum

Answer 10

E-speed or faster!

Question 11

What makes a detailed radiograph of a plane section of a solid object while blurring out the images of adjacent planes. What’s the focused area called?

Answer 11

panoramic

focal trough

Question 12

Where is film in pan

Answer 12

film in FRONT of patient

Question 13

Vertical magnification varies little with _____

Answer 13

object depth (focal spot to object distance)

Question 14

Light, pale film is from

Answer 14

UNDERexposure

Question 15

If anterior teeth look small (pic is very zoomed out), patient is biting..

Answer 15

too far onto rod (face is closer to film in front)

Question 16

what plane is horizontal from tragus to the lower part of orbit of eye

Answer 16

frankfurt plane

Question 17

If pano has exaggerated smile, patient chin is tipped ___

Answer 17

down

Question 18

Pano is __% less dose than a full mouth series

Answer 18

20

Question 19

Disadvantages of pano

Answer 19

poor definition

20-30% magnification

Question 20

What produces non-superimposed images

Answer 20

CT (computed tomography)

Question 21

What’s a Hounsfield unit

Answer 21

measurement of grey values in CT

Question 22

Isotropic resolution:

Anisotropic:

Answer 22

boxes with all 4 sides equal (much clearer)

not all sides equal

Question 23

Conebeam has between ____ sequential planar projection images of the field of view

Answer 23

150-600

Question 24

Small field of view for cone beam=
medium=
large=

Answer 24

small 10

Question 25

Difference of fan beam and cone beam with soft tissue

Answer 25

Fan beam shows all soft tissue. Cone only shows outline

Question 26

MRI 3 steps

Answer 26

magnetic field
radio frequency pulse
relaxation

Question 27

MRI signal is essentially a map of ____ion distribution in the body

Answer 27

hydrogen

Question 28

What shows up black on MRI

What shows up white

Answer 28

black=air

white=fat

Question 29

Which shows structure AND function of target tissues

Answer 29

Nuclear scintigraphy

Question 30

3 ways to look at cone beam

Answer 30

3d volume rendering
2d multiplanar
3d curve MPR

Question 31

Axial view of cone beam is look at occlusal surface of teeth (T/F)

Answer 31

TRUE

Question 32

Caries are (increased/decreased) absorption of x-ray beam

Answer 32

decreased

Question 33

Mach band is defined as a radiolucent (black) density difference between

Answer 33

enamel and dentin.

it’s an optical illusion! Can create false-positive

Question 34

For periapical, rarefying osteitis is radio___

sclerosing is radio___

Answer 34

lucent

opaque