AMY HEATH SIM AND TRT PLANNING (CH 6) Flashcards
Which of the following is a negative contrast agent?
A. Air
B. Iodine
C. Barium sulfate
D. Nonionic venous contrast
A. Air
Which of the following is not true regarding iodine contrast?
A. Can be administered intravenously
B. Kidney function must be checked prior to administration
C. Is ionic only
D. Patients allergic to shellfish should not receive iodine contras
C. Is ionic only
Prior to the administration of intravenous contrast, you should assess the patient for:
A. Shellfish allergy
B. Lung function
C. Joint pain
D. GI complications
A. Shellfish allergy
The hyoid bone is located at what vertebral level?
A. C1
B. C3
C. T1
D. T3
B. C3
The SSN corresponds to vertebral level:
A. C3
B. T3
C. T6
D. L3
B. T3
SSN stands for what?
Suprasternal Notch
An example of a positioning device is:
A. Thermoplastic mask
B. Chemical mold
C. Head holder
D. Vacuum mold
C. Head holder
- What positioning device is used to move a patient’s small bowel out of pelvic treatment fields?
A. Shoulder assistance straps
B. Bellyboard
C. Wingboard
D. Thermoplastic device
B. Bellyboard
- Thermoplastic immobilization devices are used to immobilize the:
A. Head and neck
B. Chest
C. Abdomen
D. Pelvis
A. Head and neck
- When obtaining images through conventional simulation, what is true regarding mA?
A. Controls contrast of the image
B. Represents the quality of the beam
C. Controls density of the image
D. All of the above are true
C. Controls density of the image
-Milliamperage (mA) is the quantity of beam and controls overall density.
-Kilovoltage potential (KvP) is the quality of beam and controls contrast.
- What is not a step of CT simulation?
A. Scanning the area of interest per physician order
B. Imaging with slices of 2–8 mm
C. Taking orthogonal images
D. Ensuring the patient anatomy and simulation marks are included in field of
view as the image is reconstructed.
C. Taking orthogonal images
- After CT simulation, what must be documented by the radiation therapist?
A. Gantry angle
B. Collimator angle
C. Field size
D. Patient setup
D. Patient setup
What is not included in the CTV?
A. GTV
B. Margin for motion
C. Microscopic disease
D. All of the above are included in the CTV
B. Margin for motion
- What volume accounts for the patient’s physiologic movement, such as breathing?
A. Clinical target volume
B. Internal margin
C. Gross target volume
D. Motion volume
B. Internal margin
What term describes critical structures in or near the treatment field?
A. Internal target volume
B. Organs at risk
C. Irradiated volume
D. Internal margin
B. Organs at risk
- Which of the following is true regarding the forward planning technique?
A. Plan is optimized after fields are designed
B. Computer design treatment fields based on set criteria
C. Is used for IMRT planning
D. Is only used for brachytherapy planning
A. Plan is optimized after fields are designed
- Which of the following are considered when designing fields and beam arrangements? (Choose all correct answers).
A. Total dose
B. Beam energy
C. Patient setup
A. Total dose
B. Beam energy
C. Patient setup
Which of the following tumors would best be treated with an arc treatment?
A. Central lung tumor
B. Inflammatory breast cancer
C. Ewings sarcoma
D. Nasopharyngeal tumor
A. Central lung tumor
- Which of the following beam modifying devices would not be used to compensate for missing tissue in a patient?
A. Cerrobend blocks
B. Bolus
C. Compensating filters
D. Wedges
A. Cerrobend blocks
Blocks are ____ HVL thick.
A. 1
B. 3
C. 5
D. 7
C. 5
- Multileaf collimators (MLC) are made of:
A. Lipowitz metal
B. Tungsten
C. Lead
D. Brass
B. Tungsten
***21. What device would be used in order to compensate for missing tissue as well as increase the dose to the skin?
A. Compensating filter
B. Bolus
C. Wedge
D. Hand block
B. Bolus
- What is a limitation of using wedges in a patient’s treatment plan?
A. Increased time needed for treatment planning
B. Field size limitations
C. Limitations in gantry angles that can be used
D. Little variety in available wedge angles
B. Field size limitations
- Calculate the hinge angle when using 30° wedges in a wedge pair field arrangement.
A. 60°
B. 120°
C. 180°
D. 240°
B. 120°
- The _______________ is the projection of what the treatment field will look like, from the point of view from the origin of the beam.
A. Beam’s eye view
B. Isodose distribution
C. Dose volume histogram
D. Field size view
A. Beam’s eye view
***25. What is not included in the radiation therapy treatment prescription?
A. Dose per fraction
B. Beam-modifying devices
C. Treatment volume
D. Patient position
D. Patient position
Calculate the equivalent square for a 6×12 cm field size.
A. 4×4 cm
B. 6×6 cm
C. 8×8 cm
D. 10×10 cm
C. 8×8 cm
The ________ factor is the ratio of dose at dmax for field size to dose at dmax for standard field size.
A. Attenuation
B. Output
C. Back scatter
D. Tissue maximum
B. Output
- Backscatter factor is the:
A. Ratio of dose with modifier in beam to dose without modifier in beam
B. Ratio of dose at dmax in phantom to dose at dmax in air
C. Target-to-axis distance
D. Ratio of absorbed dose at depth to dose at dmax
B. Ratio of dose at dmax in phantom to dose at dmax in air
Percent depth dose increases with:
A. Increased energy
B. Decreased field size
C. Increased depth
D. All of the above
A. Increased energy
- What is the Mayneord’s factor for a patient who was originally treated at 100 cm SSD to a depth of 5 cm with a 10× photon beam, but now needs to be
treated at 110 cm SSD?
A. 0.990
B. 0.993
C. 1.003
D. 1.010
C. 1.003
- The ratio of scattered dose at depth in phantom to scatter dose at depth in air is:
A. Tissue-air ratio (TAR)
B. Scatter-air ratio (SAR)
C. Tissue maximum ratio (TMR)
D. Tissue phantom ratio (TPR)
B. Scatter-air ratio (SAR)
- TAR is independent of:
A. Energy
B. Field size
C. Depth
D. SSD
D. SSD
-TAR increases with increased energy and increased field size, decreases with
increased depth and is independent of SSD. This factor is used in SAD calculations. TAR=BSF when measured at dmax.
What does TAR stand for?
Tissue Air Ratio
- Calculate the gap required for adjacent fields (Field A—length 12, Field B—
length 20) treated at 100 cm SSD with 6 MV photon beams to a treatment depth
of 5 cm.
A. 0.5 cm
B. 0.8 cm
C. 1.3 cm
D. 1.5 cm
B. 0.8 cm
- Calculate the monitor units needed for a patient being treated AP/PA to their
abdomen with a 12×16 cm field, SSD=100 cm, treated midplane to a depth of
7 cm, Sc=1.08, Sp=1.007, %dd=76 %, tumor dose to target is 180 cGy
A. 90 MU
B. 101 MU
C. 109 MU
D. 118 MU
C. 109 MU
- A patient is being treated isocentrically with four fields (equally weighted) to
their pelvis using 10× photons. The AP SSD is 90 cm, Right Lateral SSD is
78 cm, PA SSD is 90 cm and left lateral SSD is 82 cm. The total tumor dose per
fraction is 180 cGy. What information will you need before you can look up the
factors to complete the monitor unit calculation?
A. Field size
B. Patient position
C. Location of patient tattoos
D. Gantry angles
A. Field size
- The practical range of a 12 MeV electron beam is:
A. 3 cm
B. 4 cm
C. 6 cm
D. 12 cm
C. 6 cm
How many monitor units are needed for a lumpectomy boost electron treatment, prescribed to the 80 % isodose line? The Cfs for the treatment field
using a 10 × 10 cm cone with minimal blocking is 1.05. The dose per field is 200 cGy.
A. 211 MU’s
B. 238 MU’s
C. 190 MU’s
D. 214 MUs
B. 238 MU’s
