Fluoroscopy

Question 1

_________ uses a continuous beam of x-rays to create images of the movement of internal structures that can be viewed on a monitor.

Answer 1

Fluoroscopy

Question 2

_____ imaging is accomplished with fluoroscopy as opposed to radiography.

Answer 2

Dynamic

Question 3

The process that the exit radiation from the anatomic area of interest interacts with the input phosphor for conversion to visible light, which are converted to electrons by a photocathode, then focused by electrostatic focusing lenses, and accelerated toward an anode to strike the output phosphor is:

Answer 3

Image intensification

Question 4

The ___________ consists of a light-emitting material (like cesium iodide) to absorbs x-rays and emits light.

Answer 4

input phosphor

Question 5

This part of the image intensifier absorbs light and converts light to electrons.

Answer 5

photocathode

Question 6

This is measured in cd/m2/mR/s.

Answer 6

conversion factor

Question 7

The formula for brightness gain is:

Answer 7

brightness gain = minification gain × flux gain.

Question 8

When operated in magnification mode, the electrostatic lenses have ________ voltage.

Answer 8

increased

Question 9

A disadvantage of using magnification mode during fluoroscopy is:

Answer 9

the patient receives additional dose.

Question 10

Vidicon refers to a type of:

Answer 10

camera tube

Question 11

Increasing the mA is the way to correct a fluoroscopic image that has:

Answer 11

noise

Question 12

When the electron beam in the camera travels back and forth across, from the top to bottom, it is moving in a _____ pattern.

Answer 12

raster

Question 13

The CCD’s electrical charge from the capacitors is sent to the:

Answer 13

display monitor

Question 14

The fiber-optic bundle or optical lens system is used to:

Answer 14

link the output phosphor and camera or CCD.

Question 15

When using the mobile C-Arm unit, the x-ray tube should be positioned under the patient and the image intensifier above the patient because:

Answer 15

reduce radiation exposure to operator.

Question 16

The newest fluoroscopy systems use a flat-panel detector in place of the:

Answer 16

image intensifier

Question 17

What feature has replaced automatic brightness control (ABC) on newer fluoroscopic units?

Answer 17

Automatic exposure rate control (AERC)

Question 18

_____ reduces the number of images each second, decreases patient dose, and reduces the visibility of patient motion.

Answer 18

pulsed fluoroscopy

Question 19

Fluoroscopic equipment should be inspected every:

Answer 19

6 months

Question 20

Who invented the fluoroscope?

Answer 20

Thomas Edison

Question 21

What is the primary job of the image intensifier?

Answer 21

To increase brightness

Question 22

Light emitted by the input phosphor is directly proportional to:

Answer 22

How many x-rays it receives

Question 23

flux gain x minification gain =

Answer 23

brightness gain

Question 24

T/F: Fluoroscopy is lower in mA than radiographic mode.

Answer 24

True

Question 25

Coated with light emitting crystals to absorb electrons and emit light:

Answer 25

output phosphor

Question 26

Digital fluoroscopy is improved by:

Answer 26

CCD

Question 27

T/F: When a CCD is exposed to light, it generates and briefly stores light energy.

Answer 27

False

Question 28

The ratio of the size of the input phosphor versus the size of the output phosphor

Answer 28

minification gain

Question 29

Maximum mA station for fluoroscopy

Answer 29

5 mA

Question 30

Emitting electrons from a light source

Answer 30

Photoemission

Question 31

Focuses electrons toward the anode

Answer 31

Electrostatic lenses

Question 32

Accelerates electrons to send to the output phosphor

Answer 32

Anode

Question 33

Converts electrons into light photons

Answer 33

Output phosphor

Question 34

What is the input phosphor made of?

Answer 34

Cesium iodide

Question 35

What is the output phosphor made of?

Answer 35

Zinc Cadmium sulfide

Question 36

Converts light back to electrical signal

Answer 36

Charged coupled device (CCD)

Question 37

Collects electrical signal and sends it to the ADC (analog to digital converter)

Answer 37

Charged coupled device (CCD)

Question 38

Converts to digital signal

Answer 38

Analog to digital converter (ADC)

Question 39

The ratio of light photons at the output phosphor divided by the number of input x-ray photons

Answer 39

flux gain

Question 40

The total number of light photons produced by each electron

Answer 40

flux gain

Question 41

T/F: Magnification mode increases the input phosphor size

Answer 41

False

Question 42

Magnification mode increases: A. Spatial resolution B. Contrast resolution C. Image Brightness D. Patient Dose

Answer 42

A, B, and D

Question 43

Smaller input size = [increased/decreased] dose

Answer 43

increased

Question 44

converts x-rays to light using a flat panel detector (FPD)

Answer 44

Cesium Iodide Scintillator

Question 45

Converts light to electrons using a FPD

Answer 45

Photodiode

Question 46

Collects electrical signal using a FPD

Answer 46

Thin film transistor (TFT)

Question 47

Smaller DELs = [increased/decreased] spatial resolution

Answer 47

increased

Question 48

The loss of shape at the edges of the fluoro image

Answer 48

Pincushion artifact

Question 49

reduction of an image's brightness or saturation toward the periphery compared to the image's center

Answer 49

Vignetting

Question 50

Image in a fluoroscopic system to distort with an 'S' shape

Answer 50

S shape distortion

Question 51

The exposure switch in fluoro

Answer 51

Dead Man Switch

Question 52

Allows the image to be saved, reducing the need for another exposure

Answer 52

Last image hold (LIH)

Question 53

T/F: Electrons emitted from the photocathode are directly proportional to the intensity of light that reaches the photocathode

Answer 53

True

Question 54

Formula to find minification gain

Answer 54

(diameter of input phosphor/diameter of output phosphor)^2

Question 55

Output phosphor illumination/input exposure rate

Answer 55

Conversion factor

Question 56

Distortion of image-intensified fluoroscopic image that appears as unequal magnification is

Answer 56

pincushion appearance

Question 57

In image-intensified fluoroscopy, shape distortion is caused by:

Answer 57

the curved shape of the photocathode.

Question 58

The CCD’s electrical charge from the capacitors is sent to the:

Answer 58

display monitor

Question 59

Because the DELs of a flat-panel detector are arranged in a grid pattern (uniform columns and rows), they do not exhibit:

Answer 59

pincushion artifacts and S distortion artifacts

Question 60

Which of the following C-arm advancements can provide both static and dynamic images along with 2D and 3D during surgical procedures?

Answer 60

O-arm

Question 61

Adjusting the collimator without exposing the patient to additional radiation is known as:

Answer 61

virtual collimation

Question 62

Photoemission occurs at the:

Answer 62

Photocathode

Question 63

T/F: The ABC can be slow in responding, seen as a brief delay in the brightness adjustment.

Answer 63

True

Question 64

T/F: When using magnification mode, the fluoroscopist needs to manually set the exposure factors higher to compensate for the reduced diameter input phosphor.

Answer 64

False

Question 65

What is essentially the sum total of air kerma over the exposed area of the patient's body surface?

Answer 65

dose area product

Question 66

Which of the following are types of ionizing radiation that produce virtually the same biologic effect for equal absorbed doses in body tissue?

Answer 66

X-rays, beta particles, and gamma rays

Question 67

T/F: In fluoroscopy, pulse rate is the number of exposures per second.

Answer 67

True