CT scan serves two purposes in Nuclear medicine. They are?
A.
Attenuation correction
B.
Anatomical mapping
C.
Lesion detection
D.
All of these
E.
Attenuation correction and anatomical mapping
F.
Anatomical mapping and lesion detection
2.
Who discovered X-rays?
A.
Marie Curie
B.
Wilhelm Roentgen
C.
William Baqurel
D.
Pierre Curie
3.
Modern X-ray tubes are evacuated glass tubes with a window for produced X-rays to leave the tube.
A.
True
B.
False
4.
Inside vacuum tubes, e- are boiled off an electrically heated filament wire, called the ?
A.
Anode
B.
Cathode
C.
Electron stream filament
D.
Tungsten target
5.
These e- are accelerated to high velocity toward the ?
A.
Anode
B.
Cathode
C.
Positively charged tungsten target
D.
Anode and positively charged tungsten target
E.
All of these
6.
What causes the e- to be accelerated to high velocity?
A.
High potential difference sustained between the filament and the target
B.
Low potential difference between the filament and the target
C.
High potential difference between the glass envelope and the focusing cup
D.
Low potential difference between the tungsten target and the focusing cup
7.
Most of these e- interact with outer shell e- of the tungsten target and their kinetic energy is lost as ?
A.
Compton scatter
B.
Gamma rays
C.
Electrical discharge
D.
Heat
8.
About 2% of the e- that interact with outer shell e-of tungsten target cause the release of an X-ray by?
A.
Characteristic or Bremsstrahlung radiation
B.
Characteristic radiation
C.
Bremsstrahlung radiation
D.
None of these
9.
Characteristic X-rays produce variable energies from 0 KeV to a max defined by the maximum voltage or peak voltage applied between the filament and the target.
A.
True
B.
False
10.
Bremsstrahlung interactions are discrete.
A.
True
B.
False
11.
Larger peak applied voltage is expressed as?
A.
Milliamps
B.
mA
C.
kVp
D.
keV
12.
The greater the maximum X-ray energy, and the higher the number of x-rays created.
A.
True
B.
False
13.
The lower the energy x-rays in the x-ray beam increase rad dose to the patient but do not increase image quality.
A.
True
B.
False
14.
In order to stop a increased rad dose to the patient from lower energy x-rays what should be applied?
A.
Software filter
B.
Hardware filter
C.
Increase voltage
D.
Decrease voltage
15.
What 2 purposes do filter have on CT?
A.
Allow for increased sensitivty
B.
Consistent or homogeneous energy distribution across CT detectors
C.
Decrease noise
D.
Stops low energy x-rays
E.
Consistent or homogeneous energy distribution across CT detectors and stops low energy x-rays
16.
By removing low energy x-rays the beam is?
A.
Hardened
B.
Scattered
C.
Reduced randoms
D.
Allowing for lower temperature
17.
Beam hardening results in ?
A.
Increased rad exposure
B.
Consistent average energy
C.
Reduced amount of electricity needed
D.
18.
Higher kVp advantages?
A.
Higher rad dose to patient
B.
Decreased ability to differentiate tissue density
C.
Greater X-ray penetration; less noise; less beam hardening
D.
All of these
E.
None of these
19.
Higher kVp disadvantages?
A.
Higher rad dose to patient
B.
Decreased ability to differentiate tissue density
C.
Greater X-ray penetration; less noise; less beam hardening
D.
All of these
E.
None of these
F.
Higher rad dose to patient, and Decreased ability to differentiate tissue density
20.
Artifacts radiate from bone where lower energies were attenuated but higher pass through.
A.
True
B.
False
21.
The amount of electricity is expressed in?
A.
milliamps
B.
microamps
C.
millivolts
D.
microvolts
22.
What affects the number of total x-rays produced?
A.
The amount of electricity
B.
Time
C.
The amount of electricity and time
D.
The number of x-ray generators
23.
The byproduct of producing x-rays is?
A.
Gamma rays
B.
Noise
C.
Heat
D.
Dead time
24.
Heat is removed from the tungsten target by?
A.
Copper backing
B.
Gold backing
C.
Rapid spinning of target
D.
Casual spinning of target
E.
Copper backing and Rapid spinning of target
F.
Gold backing and Rapid spinning of target
25.
Higher mA advantages?
A.
Increased rad dose to patient
B.
Less noise, better tissue contrast
C.
Less noise
D.
Better tissue contrast
26.
Higher mA disadvantages?
A.
Increased rad dose to patient
B.
Less noise, better tissue contrast
C.
Less noise
D.
Better tissue contrast
27.
Images created using x-rays are used to image the body, the images we see are inverse shadows.
A.
True
B.
False
28.
Denser tissues such as bone appear dark on a X-ray.
A.
True
B.
False
29.
Soft tissues such as lungs appear as dark spots on x-rays.
A.
True
B.
False
30.
Like NM, x-ray using motionless x-ray source and detector is called?
A.
Planar imaging
B.
Dynamic imaging
C.
SPECT imaging
D.
None of these
31.
If X-ray data is acquired over 360 degrees around the patient, the data can be reconstructed using?
A.
Attenuation correction
B.
Back projection
C.
Filtered back projection
D.
Cine player
32.
There are 2 methods of CT, which uses a nonmoving ring of detectors?
A.
Rotate-Rotate system
B.
Stationary-Planar
C.
Rotate-Stationary system
D.
Rotate-Point and shoot system
33.
There are 2 methods of CT, which uses a moving ring of detectors and the x-ray source moves?
A.
Rotate-Rotate system
B.
Stationary-Planar
C.
Rotate-Stationary system
D.
Rotate-Point and shoot system
34.
As the x-ray source moves around the patient , at each position the tube is turned on and the patient receives _____ of x-rays.
A.
Cone
B.
Circle
C.
Fan beam
D.
slice
35.
What creates the fan beam shape?
A.
Post-patient collimator
B.
Prepatient collimator
C.
Shape of the x-ray tube
D.
Material of the target
36.
Why is the Post-patient collimator is used?
A.
Decrease scatter and set slice thickness
B.
Decrease noise
C.
Increase sensivity
D.
Decrease rad dose to patient
37.
Post-patient collimators set slice thickness except in?
A.
Gated CT
B.
SPECT
C.
Multi-slice CT
D.
Limited scans, such as hands and feet
38.
Slice thickness is is between ____ to _____
A.
0.1mm to 10nm
B.
0.2mm to 20nm
C.
0.3mm to several nm
D.
0.4mm to 40nm
39.
Slice thickness has no determination on whether a lesion can be seen?
A.
True
B.
False
40.
Adaptive Array detector is used in?
A.
CT
B.
Multi-slice CT
C.
X-ray
D.
MRI
41.
Adaptive array detectors allow varying mm detectors to be turned on or off to set slice thickness.
A.
True
B.
False
42.
There can be individual detectors that can be grouped or combined to create varying slice thickness.
A.
True
B.
False
43.
Advantages of Thinner collimation. Which of these is not correct?
A.
Less volume averaging
B.
Better resolution on sagittals and coronals
C.
Increased spatial resolution
D.
Fewer streaking artifact from high density objects
E.
None of these
44.
Disadvantage of Thinner collimation. Which of these is true?
A.
Increased noise due to less photons per slice (quantum mottle)
B.
Increased scan time (thinner slices = more slices needed per area of body)
C.
Results in more slices based on reconstruction slice thickness setting chosen
