IC MP Sample Questions
Sample Questions
Computer-Based Exams - Part I General Computer-Based Exams - Part I Clinical Computer-Based Exams - Part 2 Diagnostic Medical Physics Computer-Based Exams - Part 2 Nuclear Medical Physics Computer-Based Exams - Part 2 Therapeutic Medical Physics Download these questions in printable .pdf format
Computer-Based Examinations
PART 1: General
1. Beyond the depth of maximum dose, which statement best describes the relative behavior of dose and kerma?
A. Dose and kerma fall off equally.
B. Kerma falls off faster than dose.
C. Dose falls off faster than kerma.
D. Dose falls while kerma rises.
E. Dose rises while kerma falls.
2. At 75 degrees Fahrenheit and 1 atmosphere, a vented ionization chamber should have its reading "temperature corrected" by multiplying the reading by which factor? (Assume the ionization chamber has a calibration factor from an AAPM-accredited U.S. calibration laboratory.)
A. 0.994
B. 1.003
C. 1.006
D. 1.021
3. The mass attenuation coefficient of bone (density of 1.8 g/cm3) is 0.2 cm2/g for an 80-keV gamma ray. What percentage of 80-keV photons is attenuated by a slab of bone 4 cm thick under conditions of narrow beam geometry?
A. 36%
B. 45%
C. 55%
D. 64%
E. 76%
4. The modulation transfer function (MTF) curve is a plot of which relationship?
A. Image contrast versus resolution
B. Subject contrast versus image contrast
C. Detail detection versus viewing condition
D. System characteristics versus component characteristics
E. Image contrast versus spatial frequency
5. Reduced contrast in a therapy verification image compared with a simulator radiographic image is primarily a result of which process?
A. An increased number of pair productions
B. An increased number of Compton interactions
C. An increased number of photoelectric interactions
D. A decreased number of photoelectric interactions
E. A decreased number of Compton interactions
6. A 2 cm3 ionization chamber is placed in a radiation field of 100 R/s. The current generated is how many amperes (p air = 0.0013 g/cm3)?
A. 5.1 x 10-11 amperes
B. 6.3 x 10-10 amperes
C. 5.1 x 10-9 amperes
D. 6.3 x 10-8 amperes
E. 5.1 x 10-7 amperes
7. At a radiologist's workstation, the instantaneous exposure rate through the wall from a chest image receptor is 500 mR/h during exposures of 10 mAs at 100 kV and 100 mA. For 200 exposures per week, what is the approximate maximum exposure in mR at the workstation?
A. 0.28 mR
B. 2.8 mR
C. 28 mR
D. 280 mR
E. 2800 mR
8. Which statement best describes the phenomenon of pair production?
A. The electrons and positrons are emitted at 180° to each other.
B. Positrons and antineutrinos are produced when the interactions occur.
C. Photons with energies greater than 1.02 MeV are necessary for the interactions to occur.
D. The total energy of the incident photon is evenly divided between the kinetic energy of the pair of particles.
9. Ten 1024 x 1024 digital images with 64 shades of gray are to be transmitted at the rate of 1.049 x 105 bits/s. Approximately how long will it take to complete the transmission?
A. 10 s
B. 30 s
C. 1 min
D. 10 min
E. 1 h
10. A group of patients exhibits lifetimes that are normally distributed with a mean of 36 months and a standard deviation of 3.0 months. What percentage of these patients will survive at least 42 months?
A. 2.5%
B. 5.0%
C. 33.0%
D. 67.0%
E. 95.0%
Answers for this section:
1. A
2. C
3. E
4. E
5. D
6. D
7. B
8. C
9. D
10. A
PART 1: Clinical
1. The human typically has how many cervical vertebrae?
A. 12
B. 10
C. 7
D. 5
E. 4
2. A fetus receives a dose of 2 Gy during weeks 20-39 of pregnancy. After birth, the child has an increased risk for what condition?
A. Down syndrome
B. Leukemia
C. Microcephaly
D. Neonatal death
3. For a patient suspected of having kidney stones, what is the most appropriate examination?
A. CT
B. MRI
C. Abdominal radiography
D. Endoscopic retrograde cholangiopancreatography
E. Hysterosalpingogram
4. What is the most common location for cancer in the breast?
A. Lower inner quadrant
B. Lower outer quadrant
C. Upper inner quadrant
D. Upper outer quadrant
Answers for this section:
1. C
2. B
3. A
4. D
PART 2: Diagnostic Medical Physics
SIMPLE QUESTIONS
1. For a photo-timed radiograph, an increase in which of the following factors will increase patient skin dose?
A. Milliampere
B. Kilovolt peak
C. Patient thickness
D. Field size
E. Source-to-image distance
2. An ROI in a CT image has an intensity of -30 HU. What is the ratio of the linear attenuation coefficient for the ROI to that of water?
A. 0.70
B. 0.97
C. 1.00
D. 1.03
E. 1.30
3. As a potential contrast agent for ultrasound, which of the following materials is expected to be the strongest reflector for a fixed concentration of small (<5 nm) particles?
A. Encapsulated polymer
B. Encapsulated lipid
C. Encapsulated gas
4. In a spin echo MRI pulse sequence with TR = 2000 ms and TE = 100 ms, which anatomy feature has the highest signal intensity in a brain image?
A. Gray matter
B. White matter
C. Lens of the eye
D. CSF
5. According to NCRP 116, what is the annual occupational equivalent dose limit in Sv for an extremity?
A. 0.5 Sv
B. 1.5 Sv
C. 5 Sv
D. 15 Sv
E. 50 Sv
Answers for this section:
1. C
2. B
3. C
4. D
5. A
PART 2: Diagnostic Medical Physics
COMPLEX QUESTIONS
1. Below is shown a series of repeat measurements of the output of an x-ray tube and generator for an 80-kVp beam, 10 mAs at 1 meter. The coefficient of variation of these measurements is _____.
A. 70
B. 7.0
C. 0.7
D. 0.07
E. 0.007
|
Measurement # |
Output (mR) |
|
1 |
71.3 |
|
2 |
70.9 |
|
3 |
72.2 |
|
4 |
71.8 |
|
5 |
71.5 |
2. A 5-MHz ultrasound beam is incident on a blood vessel at an angle of 45 degrees. If the blood is moving toward the transducer, and the mean velocity is 30 cm/s, what is the mean frequency shift in kHz of the reflected beam?
A. 0.7 kHz
B. 1.4 kHz
C. 2.8 kHz
D. 5.6 kHz
E. 11.2 kHz
3. A pencil ionization chamber has an active length of 10 cm. A CT dose measurement is made with the body CTDI phantom and chamber positioned appropriately. A single axial CT scan is performed at 130 kVp, 120 mAs, and 5-mm slice thickness. The chamber reading is 110 mR. (Assume an f-factor of 0.9 cGy/R.) What is the CTDI in mGy for this measurement?
A. 12 mGy
B. 20 mGy
C. 32 mGy
D. 40 mGy
E. 44 mGy
4. For a 1.5 T MRI system using a phase encode gradient of 2.1 mT/m, at a distance of 10 cm from the null of the phase encode gradient, what is the change in frequency in kHz of protons?
A. 40.6 kHz
B. 26.8 kHz
C. 21.3 kHz
D. 8.9 kHz
E. 2.1 kHz
Answers for this section:
- E
- B
- B
- D
PART 2: Nuclear Medical Physics
SIMPLE QUESTIONS
1. What is the approximate exposure gamma ray constant for I-131 in
R-cm2/mCi-hr?
A. 0.7
B. 1.2
C. 1.6
D. 2.2
E. 3.3
2. A spatial resolution measurement of a SPECT system is performed using line sources of Tc-99m according to the NEMA protocol. If the spatial resolution (FWHM) is 10.5 mm in the center of the phantom, what is the peripheral tangential spatial resolution (FWHM) in mm at 7.5 cm from the center of the phantom?
A. 8 mm
B. 12 mm
C. 14 mm
D. 16 mm
3. Which of the following is a FALSE statement about imaging techniques?
A. Image quality is reduced when In-111 is used for imaging with a collimator designed for Tc-99m.
B. Tc-99m with a pinhole collimator can be used to image a 3-mm diameter lesion.
C. High-energy collimators will provide good spatial resolution for F-18.
D. Tungsten is a better collimator material than lead for imaging Tl-201.
E. Because the energy of Co-57 is so close to that of Tc-99m, it can be used for high-count flood correction in SPECT imaging.
4. If the minimum, mean, and maximum pixel counts in the CFOV of a smoothed intrinsic flood image are 4500, 5200, and 5500, respectively, what is the integral uniformity in percentage?
A. 5 %
B. 6 %
C. 10 %
D. 14 %
E. 15 %
5. In a gate-synchronized ventricular function study, the color-coded phase image shows a group of pixels in the apex of the left ventricle displayed in the hue assigned to the atria. What is the most likely explanation of this observation?
A. Global left ventricular hypokinesis
B. Valvular insufficiency
C. Malfunctioning software
D. Cardiac arrhythmia
E. Apical dyskinesis
Answers for this section:
1. D
2. A
3. C
4. C
5. E
PART 2: Nuclear Medical Physics
COMPLEX QUESTIONS
1. A Tc-99m radioactive tracer is removed from the kidneys by three pathways: 1) absorption in the blood at 50 percent every 3 hours; 2) excretion to the bladder at 50 percent every 2 hours; and 3) physical decay. The effective half-time of the radioactive tracer in the kidney is _____ hours.
- 1
- 2
- 4
- 6
- 11
2. A generator is eluted and yields 300 mCi of Tc-99m. What is the maximum acceptable number of microcuries of Mo-99 allowable at the time of elution in order for clinical studies to be done up to 6 hours after elution?
- 5.6
- 12
- 24
- 30
- 45
3. If annihilation radiation originates in the center of the water-filled phantom diagrammed below, the PET attenuation correction factor will be _____. (µ = 0.096 cm -1)
- 15.9
- 24.1
- 31.7
- 40.3
- 48.5
4. A Χ2 test was performed with a sample size of 10 using a long-lived source. The following results were obtained:
s n-1 = 205.5
Mean = 3752.6
The Χ2 value is _____.
A. 14.3
B. 101
C. 205
D. 3753
E. 42,256
5. The following intrinsic line spread function is recorded using a slit phantom.
|
Channel # |
Cts |
Channel # |
Cts |
Channel # |
Cts |
|
133 |
300 |
138 |
900 |
143 |
833 |
|
134 |
400 |
139 |
950 |
144 |
710 |
|
135 |
580 |
140 |
1000 |
145 |
560 |
|
136 |
675 |
141 |
970 |
146 |
480 |
|
137 |
780 |
142 |
911 |
147 |
345 |
The distance per channel is 0.4 mm. What is the intrinsic spatial resolution (FWHM) in mm?
A. 3.48 mm
B. 3.75 mm
C. 4.28 mm
D. 4.48 mm
E. 6.50 mm
Answers for this section:
- A
- C
- C
- B
- D
PART 2: Therapeutic Medical Physics
SIMPLE QUESTIONS
1. What is the reason flattening filters are used for high-energy photon beams from an accelerator?
A. To increase low-energy photons
B. To correct for the pulsing of radiation
C. To increase fluence along the central axis of the beam
D. To increase depth dose
E. To make the beam flat across the full field
2. A physician is considering hypofractionating a treatment which is usually prescribed as 50 Gy in 25 fractions, i.e., 2 Gy per fraction. If the considered dose per fraction is 3 Gy, the α/β ratio for this particular tumor is 10 Gy, and the model for biological effective dose (BED) is used, what does the approximate number of fractions become?
A. n = 5
B. n = 10
C. n = 15
D. n = 20
E. n = 25
3. According to TG-59, an ionization chamber reading is corrected to compensate for the temperature and pressure dependence of which of the following?
A. Air volume in the ionization chamber
B. Mass of air in the ionization chamber
C. Mass stopping power ratio for electrons in the ionization chamber
D. Mass stopping power ratio for electrons of the phantom material
E. Density of air in the monitor chamber
4. According to the AAPM TG-43 protocol, the anisotropy function is used to calculate doses in the vicinity of brachytherapy sources. For line sources, at points away from the perpendicular to the source’s long axis, the value of the anisotropy function decreases as which of the following changes occurs?
A. Distance from the source increases.
B. Photon energy increases.
C. Angle from the perpendicular increases.
D. Source encapsulation decreases.
E. Atomic number of the encapsulation material decreases.
5. In using kV cone-beam CT for image-guided radiation therapy of head and neck cancer, which of the following structures receives the largest imaging dose?
A. Brain stem
B. Mandible
C. Parotid
D. Lens
Answers for this section:
- E
- C
- B
- C
- B
PART 2: Therapeutic Medical Physics
COMPLEX QUESTIONS
1. The 6-MV photon beam of a linear accelerator is calibrated to deliver 1.0 cGy/MU at a depth of 1.5 cm (dmax) in a 10 × 10-cm2 field at 100 cm SSD. A patient is to be treated with an SAD setup with an open field of 30 × 30 cm2 to a depth of 10 cm. How many MU are required to give 100 cGy to this point?
TMR (d = 10, fs = 10) = 0.78
TMR (d = 10, fs = 30) = 0.83
OF (10) = 1.0
OF (30) = 1.06
A. 110 MU
B. 114 MU
C. 119 MU
D. 121 MU
2. Assuming the balloon can be considered as a perfect sphere in a MammoSite application, using an Ir-192 HDR source with a single dwell position at the center of the balloon surface, the prescribing dose is 340 cGy to a planning target volume (PTV) 1.0 cm from the balloon surface in three dimensions. The dose-volume histogram is calculated with a constant anisotropy factor for the source in a large homogeneous tissue-equivalent medium, and the maximum dose within the PTV is 710 cGy. What is the diameter of the balloon?
A. 4.0 cm
B. 4.5 cm
C. 5.0 cm
D. 5.5 cm
E. 6.0 cm
3. A patient is treated at isocenter (1 m) with a 20 × 20-cm2 field. Calculated using the data in the table below, the NCRP-defined transmission factor BSX for patient-scattered radiation is closest to which of the values given?
Workload = 500 Gy at 1 m
Occupancy factor = 1
P (uncontrolled) = 0.02 mSv/wk
α = 0.001
dsec = 5.0 m
A. 0.00001
B. 0.0001
C. 0.001
D. 0.01
E. 0.10
4. At 1 cm distance in tissue from a 0.46-mCi permanently implanted I-125 seed, what is the total dose?
A. 5.5 Gy
B. 10.5 Gy
C. 13.2 Gy
D. 30.5 Gy
F. 50.0 Gy
5. The isocenter of a 10-MV oblique photon beam is at 12-cm depth, of which 6 cm is muscle tissue and 6 cm is lung tissue. What is the difference in the dose calculated at isocenter without lung density correction and the dose actually delivered at the same point?
A. 20% higher
B. 10% higher
C. 5% higher
D. 10% lower
E. 20% lower
Answers for this section:
- A
- B
- C
- C
- B