Imaging equipment unit 1

What serves as the primary protective barrier in fluoroscopic imaging?

Image intensifier or a flat panel detector

A primary protective barrier of _____ lead equivalent is required for a fluoroscopic unit.

2 mm

The input phosphor is typically composed of _______ and converts ______ to _______.

cesium iodide; x-rays; light

A thicker input phosphor layer has a (higher or lower) absorption efficiency and (Increaseses or decreases) patient dose.

higher; decreases

What effect does a thicker input phosphor have on spatial resolution?

decreases

The photocathode converts ____ to _____

light to electrons

What charge do the electrostatic lenses have?

negative

A potential difference of ____ is maintained between the photocathode and the anode.

25,000 volts

The output phosphor is typically composed of _____ and converts _____ to ______.

zinc cadium sulfide; electrons to light

How much the image is minified from the input phosphor to the output phosphor.

1. flux gain

2. brightness gain

3. minification gain

minification gain

The ability of the image intensifier to convert xrays into light and increase brightness.

1. flux gain

2. brightness gain

3. minification gain

brightness gain

The ratio of light photons at the output phosphor to the number of light photons emitted from the input phosphor (converting a few xrays into many light photons)

1. flux gain

2. brightness gain

3. minification gain

flux gain

Magnification results in (higher/lower) patient dose, (better/worse) contrast resolution, (better/worse) spatial resolution

higher; better; better

_____ is a reduction of brightness at the periphery of the image.

vignetting

______ distortion is a result of the inaccurate control of electrons released at the periphery of the photocathode and the curved shape of to photocathode.

pincushion

Compared with the image on the input phosphor, the image on the output phosphor of the image intensifier is ( select three):

1. magnified

2. distorted

3. brighter

4. dimmer

5. inverted

6. minified

brighter, inverted, minified

As field of view (FOV) decreases in image intensification (select three):

1. output screen image is magnified

2. output screen image has more noise

3. mA increases

4. output screen image has improved resolution

5. the fical point is closer to the output phosphor

6. voltage to the focusing lenses is decreased

output screen image is magnified, mA increases, output screen image has improved resolution

Which of the following will improve the spatial resolution of image intensified images?

1. a very thin input phosphor

2. a larger diameter input screen

3. increased brightness pain

1 only

Which of the following systems functions to compensate for changes in patient/part thickness, FOV, and OID during fluoroscopic procedures?

1. automatic exposure rate control

2. electronic magnification

3. automatic resolution control

4. flux gain

automatic exposure rate control

Which of the following modes of a triple-field image intensifier will result in the highest patient dose?

1. 25 inch mode

2. 17 inch mode

3. 12 inch mode

4. diameter does not affect patient dose

12 inch mode

All of the following are components of the image intensifier, except:

1. the photocathode

2. the focusing lenses

3. the TV monitor

4. the accelerating anode

the TV monitor

Which of the following is used in fluoroscopy, replacing the image intensifiers’ television camera tube?

1. solid-state diode

2. charge coupled device

3. photostimulable phosphor

4. vidicon tube

charge coupled device

In fluoroscopy, the automatic brightness control is used to adjust the:

1. kilovoltage (kV) and the milliamperage (mA)

2. backup timer

3. milliamperage (mA) and time

4. kilovoltage (kV) and time

kilovoltage (kV) and the milliamperage (mA)

The image-intensifier tube’s input phosphor functions to convert:

1. kinetic energy to light

2. x-rays to light

3. electrons to light

4. fluorescent light to electrons

x-rays to light

The total brightness gain of an image intensifier is the product of:

1. flux gain

2. minification gain

3. focusing gain

1 and 2

Which number in the figure to the right represents magnification mode?

1. 1

2. 2

3. 7

4. 8

8

Which number in the figure represents electrostatic focusing lens?

1. 5

2. 6

3. 4

4. 2

4

Advantages of CCDs over the use of television cameras in image intensification include which of the following?

1. compact size

2. improved resolution

3. higher DQE

1, 2, and 3

The image intensifier’s input phosphor generally is composed of?

1. cesium iodide

2. zinc cadmium sulfide

3. gadolinium oxysulfide

4. calcium tungstate

cesium iodide

The brightness level of the fluoroscopic image can vary with:

1. milliamperage

2. kilovoltage

3. patient thickness

1, 2, and 3

Moving the image intensifier closer to the patient during fluoroscopy:

1. decreases the SID

2. decreases patient dose

3. improves image quality

1, 2, and 3

Which of the following is/are associated with magnification fluoroscopy?

1. higher patient dose than non-magnification fluoroscopy

2. higher voltage to the fucusing lenses

3. image intensifier focal point closer to the input phosphor

1, 2, and 3

The device that receives the remnant beam, converts it into light, and then increases the brightness of that light is the:

1. charge coupled device (CCD)

2. spot image device

3. image intensifier

4. television monitor

image intensifier

When using the smaller field in a dual-field image intensifier:

1. the image is magnified

2. the image is brighter

3. a larger anatomic area is viewed

1 only

Advantages of smaller diameter input screens in image intensification include which of the following?

1. improved resolution

2. availability of large FOV

3. image magnification

1 and 3

To maintain image clarity in an image-intensifier system, the path of electron flow from the photocathode to the output phosphor is controlled by:

1. the accelerating anode

2. electrostatic lenses

3. the vacuum glass envelope

4. the input phosphor

electrostatic lenses

What is A?

indirect flat panel

What is B?

direct flat panel

What is C?

cesium iodide

What is D?

amorphous silicon

What is E?

amophous selenium

The ____ signal is the electronic signal which carries information from the charged coupled device to the TV monitor?

1. uptake

2. coupling

3. video

4. monitor

video

The diameter or size of the _____ is the value used to describe the size of the image intensifier.

1. output phosphor

2. photocathode

3. input phosphor

4. anode

input phosphor

Which one of the following modes is an image intensifier would produce an image with the most magnified image?

1. 5 inch mode

2. 9 inch mode

3. 12 inch mode

4. 14 inch mode

5 inch mode

The reduction of field of view (FOV) size, 24 cm to 12 cm, in a dual field image intensifier can be accomplished by:

1. increasing the size of the input phosphor

2. decreasing the size of the output phosphor

3. increasing the voltage on the electrostatic lenses

4. decreasing the potential difference across the tube

increasing the voltage on the electrostatic lenses

Which mode of a triple field image intensifier will have the highest minification ratio gain factor?

1. 5 inch mode

2. 9 inch mode

3. 12 inch mode

4. 14 inch mode

14 inch mode

The reduction of brightness at the periphery of image display of an image intensified fluoroscope is termed:

1. pincuchion reduction

2. vignetting

3. fluctuation reduction

4. brightness falloff

vignetting

The principal purpose of employing image-intensified fluoroscopy is to:

1. enlarge the image for better viewing

2. raise the level of image brightness

3. increase the patient dose during fluoroscopy

4. act as a means of storing the image

raise the level of image brightness

The image intensifier tube is a/an ______ tube.

1. gas filled

2. gas evacuated

3. oil filled

4. fluid filled

gas evacuated

During a conventional fluoroscopic examination, the fluoroscopic milliamperage is:

1. less than 5 mA

2. 10 to 20 mA

3. 50 to 75 mA

4. 100 to 150 mA

less than 5 mA

What is the total brightness gain for an image intensifier tube with a minification gain of 50 and a flux gain of 75?

1. 500

2. 1020

3. 1550

4. 3750

5. 5000

3750

The device in the image intensifier tube that converts x-rays into light is the:

1. input phosphor

2. photocathode

3. accelerating anode

4. output phosphor

input phosphor

Most modern image intensifier tubes utilize an output phosphor composed of:

1. barium lead sulfate

2. zinc cadmium sulfide

3. calcium tungstate

4. cesium iodide

zinc cadmium sulfide

At least how many monitors are required for digital fluoroscopy?

1. 1

2. 2

3. 3

4. 4

2

A charge-coupled device used in digital fluoroscopy provides high:

1. signal-to-noise ratio

2. spatial resolution

3. detective quantum efficiency

4. patient dose

1, 2, and 3

Dynamic radiography is:

1. radiography which produces images of the body at one point in time

2. recording on a radiograph only selected layers within the body

3. radiography in motion

4. procedures which produce depth perception

radiography in motion

THe increased brightness of an image due to accelerated electrons traveling across to the output phosphor (and convertinga few xrays into many light photons) is called:

1. image gain

2. minification gain

3. total brightness gain

4. flux gain

flux gain

The detector used for direct capture in digital radiography/fluoroscopy is made up of:

1. cesium iodide + silicon photodiodes

2. amorphous selenium

3. CCD sensors

4. barium fluorohalide

amorphous selenium

Brightness gain for an image intensifier is typically in the range of:

1. 50 - 75

2. 100 - 1,000

3. 3,000 - 4,000

4. 5,000 - 30,000

5,000 - 30,000

Which of the following components found in digital fluoroscopy is NOT found in conventional fluoroscopy?

1. a video monitor

2. analog-to-digital converter (ADC)

3. automatic brightness control (ABC)

4. an image intensifier

analog-to-digital converter (ADC

The purpose of a “scintillator” in a flat-panel receptor is to:

1. absorb light photons and emits x-ray photons

2. absorb x-ray photons and emit light photons

3. absorb electrons and emit light photons

4. absorb light photons and emit electrons

absorb x-ray photons and emit light photons

What directly influences the number of electrons collected in a detector element (DEL)?

1. exposure to image receptor

2. exposure field recognition

3. threshold detection level

4. histogram analysis

exposure to image receptor

How magnifies is the image of a 30/20/10 in the 20 cm mode compared to the 30 cm mode?

1. 0.75 times

2. 1.65 times

3. 1.5 times

4. 3.0 times

1.5 times

How much higher is the patient dose of a 30/20/10 in the 20 cm mode compared to the 30 cm mode?

1. 0.13 times higher

2. 2.25 times higher

3. 5.3 times higher

4. 7.7 times higher

2.25 times higher

A high signal-to-noise ratio (SNR) provides an image with:

1. poor spatial resolution

2. higher spatial resolution

3. poor contrast

4. higher distortion

higher spatial resolution

During digital fluoroscopy the x-ray beam is typically:

1. continuous and at higher mA

2. continuous and at lower mA

3. pulsed

4. produced by a TV camera tube

pulsed

The use of an image receptor with ____ DQE can result in _____ patient dose.

1. low; lower

2. high; lower

3. high; higher

4. low; tripled

high; lower

Which one of the following modes in an image intensifier would produce an image with the best/highest spatial resolution?

1. 15 cm

2. 23 cm

3. 30 cm

4. 43 cm

15 cm

During digital fluoroscopy:

1. the x-ray beam is continuous and at higher mA

2. the x-ray beam is continuous and at lower mA

3. the x-ray beam is pulsed

4. the x-ray beam is produced by a TV camera tube

the x-ray beam is pulsed

In the image intensifier tube, total brightness gain is a product of what?

1. total light emitted at photocathode

2. diameter of input phosphor times diameter of output phosphor

3. intensification factor: brightness without an image intensifier divided by brightness with an image intensifier

4. flux gain times minification gain

flux gain times magnification gain

Which of the following measures the efficiency of a system to convert the x-ray input signal into a useful output signal?

1. modulation transfer function

2. detective quantum efficiency

3. exposure latitude

4. spatial resolution

detective quantum efficiency

The minification gain of an image intensifier increases with increasing:

1. output phosphor size

2. kVp

3. input phosphor size

4. mAs

input phosphor size

The _____ signal is the electronic signal which carries information from the charged coupled device to the TV monitor.

1. uptake

2. coupling

3. video

4. monitor

video

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

1. input phosphor

2. output phosphor

3. photocathode

4. electron gun

photocathode

Compared with the image on the input phosphor, the image on the output phosphor of the image intensifier is (select 3):

1. magnified

2. brighter

3. distorted

4. dimmer

5. inverted

6. minified

2, 5, and 6

A field of view (FOV) decreases in image intensification (select 3):

1. output screen image is magnified

2. output screen image has more noise

3. mA increases

4. output screen image has improved resolution

5. the focal point is closer to the output phosphor

6. voltage to the focusing lenses is decreased

1, 3, and 4

Which of the following will improve the spatial resolution of image-intensified images?

1. a very thin input phosphor layer

2. a larger diameter input screen

3. increased total brightness gain

1 only

Which of the following systems functios to compensate for changes in patient/part thickness, FOV and OID during flat-panel detector fluoroscopic procedures?

1. automatic exposure rate control

2. electronic magnification

3. automatic resolution control

4. flux gain

automatic exposure rate control

All of the following are components of the image intensifier, except:

1. the photocathode

2. the focusing lenses

3. the TV monitor

4. the accelerating anode

the TV monitor

Which of the following is used in digital fluoroscopy, replacing the image intensifiers television camera tube?

1. solid-state diode

2. charge coupled device

3. photostimulable phosphor

4. vidicon tube

charge coupled device

In fluoroscopy, the automatic brightness control is used to adjust the:

1. kV and mA

2. backup timer

3. mA abd time

4. kV and time

kV and mA

The image-intensifier tubes input phosphor functions to convert:

1. kinetic energy to light

2. x-rays to light

3. electrons to lige

4. fluorescent light to electrons

x-rays to light

The total brightness gain of an image intensifier is the product of:

1. flux gain

2. minification gain

3. focusing gain

1 and 2

Advantages of CCDs over the use of television cameras in image intensification include which of the following?

1. compact size

2. improved resolution

3. higher DQE

1, 2, and 3

The image intensifiers input phosphor generally is composed of?

1. cesium iodide

2. zinc cadmium sulfide

3. gadolinium oxysulfide

4. calcium tungstate

cesium iodide

The brightness level of the fluoroscopic image can vary with:

1. milliamperage

2. kilovoltage

3. patient thickness

1, 2, and 3

Moving the image intensifier closer to the patient during fluoroscopy:

1. decreases the SID

2. decreases patient dose

3. improves image quality

1, 2 and 3

Which of the following is/are associated with magnification fluoroscopy?

1. higher patient dose than non-magnification fluoroscopy

2. higher voltage to the focusing lenses

3. image intensifier focal point closer to the input phosphor

1,2, and 3

The device that received the remnant beam, converts it into light, and then increases the brightness of that light is the:

1. charge coupled device

2. spot image device

3. image intensifier

4. television monitor

image intensifier

When using the smaller field in a dual-field image intensifier:

1. the image is magnified

2. the image is brighter

3. a larger anatomic area is viewed

1 only

Advantages of smaller diameter input screens in image intensification include which of the following?

1. improved resolution

2. availability of large FOV

3. image magnification

1 and 3

To maintain image clarity in an image-intensifier system, the path of electron flow from the photocathode to the output phosphor is controlled by:

1. the accelerating anode

2. electrostatic lenses

3. the vacuum glass envelope

4. the input phosphor

electrostatic lenses

The fixed spatial resolution characteristic of direct digital systems is determined by the:

1. TFT and DEL size

2. sampling frequency

3. laser scanner

4. PSP thickness

TFT and DEL size

The components of a detector element (DEL) include which three of the following?

1. sensing area

2. TFT

3. capacitor

4. ADC

5. CCD

1, 2 and 3

The part of the detector element (DEL) that stores electrical charges is the:

1. capacitor

2. TFT

3. sensing area

4. CCD

capacitor

The part of the detector element (DEL) that functions as a switch/gate to release charges for readout is the:

1. capacitor

2. TFT

3. sensing area

4. CCD

TFT

As window width increases:

1. contrast scale increases

2. contrast scale decreases

3. brightness increases

4. brightness decreases

contrast scale increases

In digital imaging, thin film transistor (TFT) and detector element (DEL) size is related to:

1. contrast

2. brightness

3. spatial resolution

4. plate size

spatial resolution

The ratio of the pixel/DEL’s sensing area of the pixel/DEL itself refers to:

1. fill factor

2. DQE

3. spatial reolution

4. sign-to-noise ratio

fill factor

The main diffrence between a direct-capture and an indirect-capture DR panel is that:

1. direct capture has no scintillator

2. direct capture uses a photostimulable phosphor

3. with direct capture, light is detected by CCDs

4. with direct capture, light is detected by TFTs

direct capture has no scintillator