qa exam 2

Because of the OSL dosimeter's sensitivity down to as low as 10 µSv for x-ray and gamma ray photons in the energy range 5 keV to 40 MeV, it is an excellent and practical monitoring device for

A) Employees working in high-radiation environments and for non-pregnant workers. 
B) Employees working in low-radiation environments and for pregnant workers.
C) Members of the general public not occupationally employed.
D) Pregnant employees working in high-radiation environments.

B) Employees working in low-radiation environments and for pregnant workers.

Which component(s) of the Geiger-Muller survey meter alerts the operator to the presence of ionizing radiation?

A) The shield covering the probe's sensitivity chamber
B) An audio amplifier and speaker
C) The metal that encloses the counter's gas-filled tube
D) The meter scale

B) An audio amplifier and speaker

The front of the white paper packet of the optically stimulated luminescence (OSL) dosimeter

A) may be color coded to facilitate correct usage and placement of the dosimeter on
the body of occupationally exposed personnel.
B) must not have any type of printing on it.
C) must be radiopaque.
D) must never be exposed to ionizing radiation.

A) may be color coded to facilitate correct usage and placement of the dosimeter on
the body of occupationally exposed personnel.

Which device provided immediate exposure readout? 

Ion storage

Which of the following personnel monitoring devices can be used to provide an immediate exposure readout for a radiation
worker?

1. Personnel digital ionization dosimeter
2. Optically stimulated luminescence dosimeter without an in-house reader
3. Pocket ionization chamber
4. Thermoluminesence dosimeter

A) 1 and 2 only
B) 1 and 3 only
C) 1 and 4 only
D) 2 and 4 only

B) 1 and 3 only

Which of the following instruments is called a cutie pie?

A) Geiger-Muller survey meter
B) Ionization chamber-type survey meter
C) Optically stimulated luminescence dosimeter
D) Proportional counter

A) Geiger-Muller survey meter

In general, which of the following can human cells do?

1. Move, grow, react, and protect themselves
2. Repair damage and regulate life processes
3. Reproduce

4. All of the above

All of the above

Which of the following terms best describes the ability of an imaging system to create separate images of closely spaced high-contrast objects?

A) Screen speed
B) spatial resolution
C) contrast resolution
D) quantum mottle

B) spatial resolution

A DR flat panel detector element (DEL) size will help to determine which of the following?

A) contrast resolution
B) detective quantum efficiency (DDQE)
C) spatial resolution
D) dynamic range

C) spatial resolution

The window width setting in a digital imaging system is used to manipulate which of the following values?

A) pixel brightness
B) spatial resolution
C) temporal resolution
D) image contrast

D) image contrast

The type of contrast that is caused by variations in the tissue density within the anatomical part to be imaged, defines which of the following?

A) image contrast
B) subject contrast
C) inherent contrast
D) none of the answer options are correct

B) subject contrast

The ability of an imaging system to distinguish structures with similar x-ray transmission as separate entities is known as:

A) contrast resolution
B) spatial resolution
C) temporal resolution
D) spectral matching

A) contrast resolution

Focal spot size can increase with age and use and with increases in the mA station selection. This is know as ____ _____ ________. To evaluate this, use ___ _____ camera test.

Focal spot blooming; pin hole

Which of the following of a quality control program for radiographic equipment include?

(1) visual inspection

(2) environmental inspection

(3) performance testing?

A) 1 and 2 only
B) 2 and 3 only
C) 1 and 3 only
D) 1, 2, and 3

D) 1, 2, and 3

The minimum half-value layer for x-ray units operating at 80 kVp is ______ mm of Aluminum.

A) 1.3
B) 1.5
C) 2.3
D) 2.5

C) 2.3

The variability allowed for mAs linearity is +/- ___________%.

A) 2
B) 5
C) 10
D) 20

C) 10

The maximum variability allowed for the reproducibility of exposure is +/- __________%.

A) 2
B) 5
C) 10
D) 20

B) 5

Any variations between the stated kVp on the control panel and the measured kVp must be +/- __________%.

A) 2
B) 5
C) 10
D) 20

B) 5 (or 10?)

Two common quality control tests that should be performed on grids are grid _____ and grid _____ tests.

A) ratio; frequency
B) alignment; uniformity
C) ratio; alignment
D) uniformity; ratio

B) alignment; uniformity

The minimum filtration required for general-purpose radiographic systems is _____ mm Al.

A) 2.0
B) 2.1
C) 2.5
D) 3.0

C) 2.5

Data for determining repeat rates should include at least ____ patients to obtain a statistical
sample large enough for valid results.

A) 100
B) 150
C) 250
D) 500

C) 250

Which of the following can occur as a result of a double set of grid lines?

A) Grid misalignment
B) Film fog
C) Static artifacts
D) Moiré effect

D) Moiré effect

In departments with a quality management program in place, the greatest number of repeat images is caused by which of the following?

A) equipment problems
B) Image fog
C) Patient motion
D) Positioning error

D) Positioning error

A digital radiograph has a pixel bit depth of 8, which means it can display how many shades of gray?

256

DQE is most specifically a measure of:
a. Contrast resolution
b. Digital data file size
c. Image noise
d. Spatial resolution
e. X-ray absorption

e. X-ray absorption

Detected Quantum Efficiency (DQE) is a measure of what?

DQE is a measure of signal-to-noise ratio and dose efficiency
It is calculated as a percentage of signal-to-noise (SNR) ratios of detector output and detector input

What is the term for brightness of light projected on a given surface?

Illuminance

Humans can detect how many shades of gray?

32

luminance is a measurement of the brightness of the bulb or the source TRUE OR FALSE

TRUE

Which of the following terms is the unit most commonly  used to measure luminance?  

Nit

If the bit depth of a magnetic resonance imaging scanner is 12 bits, how many shades of gray can be present in the image?

A) 1024
B) 2048
C) 4096
D) 8192

C) 4096

Which of the following controls contrast in a digital system?

A) Look-up table
B) Histogram
C) High-frequency laser
D) Analog-to-digital converter

A) Look-up table

controlling or limiting aspect of an imaging system its ability to display the contrast.

Bit depth

Shades of gray is controlled by which post-processing tool?

A) Window width
B) Masking
C) Annotations
D) Window level

A) Window width

Noise reduces contrast as well as detail True or False?

True

What is true about signal to noise ratio?

High signal low noise

in signal to noise the signal refers to exposure to the image receptor true or false

True

What gives the best image detail?

Large matrix

In DR the dels determine the sampling frequency and therefore the spatial resolution true or false

True

What is the unit of spatial resolution?

line pairs per millimeter (lp/mm)

the optimal efficiency in a generator the waveform ripple should be what?

1%

beam restriction is within what?

2%

HVL Stands for?

half value layer

HVL Measures?

test of quality for filtration using aluminum.

A synchronous spinning top test is used to test

timer accuracy or rectifier function in three-phase equipment.

Pinhole test evaluates what?

focal spot size

If a necklace shows up on an image, it is classified as what?

artifact

A blotchy or grainy appearance on an image receptor?

Noise

Zebra pattern is usually what?

Moire effect

Why would we get ghosting on a CR machine?

IR is not properly erased

TRUE OR FALSE CR plate could be fogged but a DR detector CANNOT

True

What is a common artifact?

Motion

What is another term for moire effect?

Aliasing

HOW MANY BITS MAKE A BYTE?

8 BITS

Bit binary digit numbers

0 for off and 1 for on

What is MTF

Used to measure spatial resolution or how well sees objects that are close together