1. Fluro 1

Question 1

Depending on patient size, part thickness, or pathologies present inside the patient, image brigthness during a fluorscopic exam is maintained by automatically varying the kVp and/or mA by this feature:

flux gain
photoemission
minification gain
automatic brightness control (ABC)

Answer 1

automatic brightness control (ABC)

Question 2

Internal scatter radiation in the form of x-rays, electrons, and light, can reduce the contrast of image intensifiers through a process called:

vignetting (pincusion distortion)
modulation transfer function (MTF)
last image hold
veiling glare

Answer 2

veiling glare

Question 3

The ____________________ in the image intensifier emits electrons when it is stimulated by light photons.

Input phosphor
Output phosphor
Photocathode
Electron gun

Answer 3

Photocathode

Question 4

Electrons hit the _______________ after passing through the anode.

Photocathode
Tube housing
Output phosphor
Focusing lens

Answer 4

Output phosphor

Question 5

Most image intensifiers are of the multifield type which allow for image magnification (example a common trifield tube is 25/17/12 cm). The numeric dimensions refer to the _____________ of the image intensifier (II).

photocathode
electrostatic lenses
output phosphor
input phosphor

Answer 5

input phosphor

Question 6

The input phosphor on an image intensifier is made of:

Molybdenum
Sodium-Activated Cesium Iodide
Barium Strontium-Sulfate
Zinc Cadmium Sulfide

Answer 6

Sodium-Activated Cesium Iodide

Question 7

Depending on the equipment type, light emitted from the output phosphor of an image intensifier can be collected and converted to an electronic signal by the:

1. charge-coupled device (CCD)
2. anode
3. electrostatic lenses
4. television camera

1 and 4
1, 2, and 4
3 and 4
1, 2, 3, and 4

Answer 7

1 and 4

Question 8

The output phosphor of the image intensifier is composed of:

Graphite
Silver-Activated Zinc Cadmium Sulfide
Crystallized Silicon
Cesium iodide

Answer 8

Silver-Activated Zinc Cadmium Sulfide

Question 9

The photocathode responds to the light produced at the input phosphor by emitting electrons through a process called:

brightness gain
thermionic emission
photoemission
veling glare

Answer 9

photoemission

Question 10

What is the minification gain for an image intensification tube with an input screen diameter of 9 inches and an output screen diameter of 1 inch?

81
9
27
18

Answer 10

81

Input Diameter 2 ÷
Output Diameter 2

Question 11

What is the Brightness Gain for an image intensifier with a 9” input phosphor, 1” output phosphor, and a flux gain of 80?

11,520
720
6,480
81

Answer 11

6,480

Minification Gain
(input diamater2 ÷ output diamater2)
x Flux Gain

Question 12

Electrostatic lenses are used to accelerate and focus:

X-ray photons
Light photons
Electrons
Scatter photons

Answer 12

Electrons

Question 13

In order to magnify an image during a fluoroscopic exam, the voltage to the _______________ must be increased.

Anode
Input Phosphor
Electrostatic Lens
Output Phosphor

Answer 13

Electrostatic Lens

Question 14

Fluoroscopy allows for continuous imaging of a patient’s internal structures. If the radiologist observes something during a fluoroscopic exam and would like to preserve that image for further study, what type of image can be taken?

Flat Plate
KUB
Topogram
Spot Film

Answer 14

Spot Film

Question 15

With the image intensifier, viewing the fluoroscopic image in magnification mode increases __________________.

Contrast resolution
Spatial resolution
Patient Dose
All of the above

Answer 15

All of the above

Question 16

The number of light photons emitted within the image intensifier is _______________ to the amount of x-ray photons exiting the patient.

Inversely proportional
Directly proportional
Unrelated
Unequal

Answer 16

Directly proportional

Question 17

During Fluoroscopy, the SOD on a fixed unit cannot be less than ______________ inches.

20 in (50 cm)
40 in (100 cm)
12 in (30 cm)
15 in (38 cm)

Answer 17

15 in (38 cm)

Question 18

The biggest disadvantage of using magnification during image intensified fluoroscopic imaging is:

Increased quantum mottle
Decreased spatial resolution
Decreased contrast resolution
Increased patient dose

Answer 18

Increased patient dose

Question 19

The input phosphor of the image intensifier converts _______________ to _______________.

Electrons, light
Light, electrons
X-rays, light
X-rays, electrons

Answer 19

X-rays, light

Question 20

The photocathode is a thin metal layer bonded directly to the input phosphor and is composed of a photoemissive material called:

Cesium and Antimony
Barium Strontium Sulfate
Calcium Tungstate
Zinc-Cadmium Sulfide

Answer 20

Cesium and Antimony

Question 21

The output phosphor absorbs ______________ and emits ______________.

Electrons, light photons
X-ray photons, light photons
Light photons, electrons
Light photons, x-ray photons

Answer 21

Electrons, light photons

Question 22

With image intensified fluoroscopy, there is a reduction of brightness seen at the periphery of the image because objects positioned furthest from the center of the input phosphor are inherently unfocused. This type of distortion is called:

last image hold
lens coupling
vignetting (pincusion distortion)
modution transfer function (MTF)

Answer 22

vignetting (pincusion distortion)

Question 23

X-rays that exit the patient and enter the image intensifier first interact with the:

Output phosphor
Input Phosphor
Photocathode
Anode

Answer 23

Input Phosphor

Question 24

What is the magnification factor for an image viewed with an image intensification tube with an input screen diameter of 9 inches that is using a 3-inch diameter area during magnification?

6
4.1
27
3

Answer 24

3

input diamater ÷
input diamater during mag

Question 25

Regardless of part thickness, part composition, and collimation, Automatic Brightness Control (ABC) maintains brightness of the image by varying:

kVp and/or mA
Collimation
Monitor settings
Anode voltage

Answer 25

kVp and/or mA