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WorksheetsPRUEBA GENERAL
Total questions: 22
Worksheet time: 12mins
A treatment plan is normalized to 100% at isocenter and prescribed 180cGy per fraction for 28 fractions to the 95% isodose line. The hot spot is 112%. What is the total maximum point dose for this plan?
56.4 Gy
59.4 Gy
50.4 Gy
61.7 Gy
A delivery of 200MU with an open beam is known to deliver the correct dose to a target. How many monitor units are required to deliver the same dose to the same target using a wedge with a wedge factor of 0.85?
170MU
270MU
200MU
235MU
Select all decay products emitted in a continuous energy spectrum
Positron emitted by Beta+ Decay
Gamma ray emitted from Internal Conversion
Alpha particle emitted by Alpha Decay
Characteristic x-rays emitted after Electron Capture
Electron emitted by Beta- Decay
The specific heat of soft tissue is 4186J/kg-C. How much dose is required to raise the temperature of soft tissue by 1 degree Celsius?
6Gy
25116Gy
4186Gy
698Gy
A radionuclide is observed to decay to 33.3% of its initial activity in 36.6 days. What is the decay constant of the radionuclide?
0.36
0.18
0.06
0.03
It is safe to stand at 1 meter from a certain 100mCi source for 1 hour. How long can someone stand 4 meters from 500mCi of that source?
1.6 hours
3.2 hours
0.3 hours
0.8 hours
F-18 is most commonly produced using what?
Nuclear reactor
Cyclotron
Radionuclide generator
Linear accelerator
What is the half-life of 15O?
10 minutes
110 minutes
2 minutes
20 minute
PET scanners have an axial spatial resolution of about
3-4mm
1-2mm
6-10mm
<1mm
Compute the energy of a photon with a 15m wavelength
212neV
1.7neV
82neV
38neV
What is the NCRP 116 occupational effective dose limit for the hands?
50 mSv
100 mSv
150 mSv
500 mSv
True or False: The daughter of beta- decay is an isobar
True
False
Which artifact could be caused by sampling too few projections?
The die in a diode detector is commonly made of what?
Doped epoxide resin
Silicon
Tungsten
Germanium
All of the following are limiting factors for PET spatial resolution except
Local tissue density
Thickness of detector crystals
Total activity injected
Decay energy of isotope
Which of the following are not common PET imaging radionuclides?
F-18
Tc-99m
N-13
C-11
A dose calibrator uses what type of detector?
Well-type ionization chamber
NaI scintillator
Proportional counter
Fluke 481 meter
What are the impacts of a filter on a kV x-ray unit? (select all that apply)
Increases output
Increases patient attenuation
Reduced HVL
Hardens the beam
Which factors would increase the HVL of a diagnostic x-ray beam? (Select all that apply)
Increasing exposure time
Removing beam filterwrong
Increasing the kVp
Increasing the kVp
Increasing mA
What is the axial resolution of an ultrasound with a spatial pulse length of 5mm?
0.5mm
2.5mm
5mm
10mm
An ultrasound transducer spends a total of 18 seconds pulsing per minute. What is its duty factor?
70%
60%
40%
30%
A T2 weighted image uses what pulse sequence?
TR = T1 and TE < T2
TR > T1 and TE = T2
TR = T1 and TE = T2
TR > T1 and TE < T2
