RTTT214 Midterm Review (Dos 2)
Study online at https://quizlet.com/_i1ciq8
1. The most important characteristics of the electron beam isodose curves that
influence treatment planning are:
A constriction of 80% to 90% isodose curves
B ballooning (or lateral spred) of 50% to 20% isodose curves
C therapeutic depth
D all of the above: D all of the above
2. Treatment planning and delivery systems are rapidly evolving to accomplish
all of the following except:
A increase tumor effects
B reduce normal tissue damage
C improve patient safety
D decrease patient care: D decrease patient care
3. Conformal treatment improves tumor control.
A Yes
B No: A Yes
4. Which of the following is not an advantage of using a multifield approach?
A Minimizes side effects
B Increases integral dose
C Reduces a potentially high dose in any single area
D Provides more homogeneous dose distribution around target: B Increases integra
dose
5. The calculation of dose at a point away from the central axis requires a
knowledge of the:
A off-axis ratio
B tissue-phantom ratio
C photon fluence
D photon flux
E kerma: A off-axis ratio
, RTTT214 Midterm Review (Dos 2)
Study online at https://quizlet.com/_i1ciq8
6. The concept of tissue-air ratio (TAR) is most commonly employed for calcula-
tions involving:
A Overlapping fields
B SSD varying fields
C Separated fields
D Opposed fields: B SSD varying fields
7. As the depth increases, the PDD:
A increases
B decreases
C remains the same
D there is no effect: B decreases
8. Which of the following is an advantage of HDR over LDR?
A HDR is noninvasive
B HDR dosimetry is simpler
C Treatment time is decreased from 72 hours to 24 hours
D HDR can be given on an oupatient basis: D HDR can be given on an oupatient basis
9. Patients with gynecological malignancies have an increased risk of develop-
ing a thrombosis when treated with:
A HDR
B external beam
C LDR
D external beam and HDR: C LDR
10. A lesion is being treated using a 100 degree arc rotation. The midpoint of the
tumor volume is 5 cm. The isocenter should be placed at:
A 0 cm
B 2.5 cm
C 5 cm
D 7.5 cm: D 7.5 cm
, RTTT214 Midterm Review (Dos 2)
Study online at https://quizlet.com/_i1ciq8
11. Extended SSDs are used for
1. total body irradiation
2. large mantle fields
3. treating head and neck cancers: 1&2
12. Bragg peak is:
A An ionization maximum near the end of the range of a heavy charged particle
B A maximum in the curve of activity and time for a patient and daughter
radionuclide in equilibrium
C A maximum concentration of Compton interactions
D The maximum activity of an isotope: A An ionization maximum near the end of the range of a
heavy charged particle
13. Organs that can be affected by motion are the:
1. lung
2. liver
3. pancreas: 1,2,3
14. Which of the following is not used for brachytherapy treatments?
A cesium
B cobalt
C iodine
D iridium: B cobalt
15. The BAT system uses __________ energy to localize the treatment target.
A x-ray
B microwave
C radiofrequency
D ultrasound: D ultrasound
16. Which of the following accounts for target motion and uncertainty in posi-
tioning?
A GTV
Study online at https://quizlet.com/_i1ciq8
1. The most important characteristics of the electron beam isodose curves that
influence treatment planning are:
A constriction of 80% to 90% isodose curves
B ballooning (or lateral spred) of 50% to 20% isodose curves
C therapeutic depth
D all of the above: D all of the above
2. Treatment planning and delivery systems are rapidly evolving to accomplish
all of the following except:
A increase tumor effects
B reduce normal tissue damage
C improve patient safety
D decrease patient care: D decrease patient care
3. Conformal treatment improves tumor control.
A Yes
B No: A Yes
4. Which of the following is not an advantage of using a multifield approach?
A Minimizes side effects
B Increases integral dose
C Reduces a potentially high dose in any single area
D Provides more homogeneous dose distribution around target: B Increases integra
dose
5. The calculation of dose at a point away from the central axis requires a
knowledge of the:
A off-axis ratio
B tissue-phantom ratio
C photon fluence
D photon flux
E kerma: A off-axis ratio
, RTTT214 Midterm Review (Dos 2)
Study online at https://quizlet.com/_i1ciq8
6. The concept of tissue-air ratio (TAR) is most commonly employed for calcula-
tions involving:
A Overlapping fields
B SSD varying fields
C Separated fields
D Opposed fields: B SSD varying fields
7. As the depth increases, the PDD:
A increases
B decreases
C remains the same
D there is no effect: B decreases
8. Which of the following is an advantage of HDR over LDR?
A HDR is noninvasive
B HDR dosimetry is simpler
C Treatment time is decreased from 72 hours to 24 hours
D HDR can be given on an oupatient basis: D HDR can be given on an oupatient basis
9. Patients with gynecological malignancies have an increased risk of develop-
ing a thrombosis when treated with:
A HDR
B external beam
C LDR
D external beam and HDR: C LDR
10. A lesion is being treated using a 100 degree arc rotation. The midpoint of the
tumor volume is 5 cm. The isocenter should be placed at:
A 0 cm
B 2.5 cm
C 5 cm
D 7.5 cm: D 7.5 cm
, RTTT214 Midterm Review (Dos 2)
Study online at https://quizlet.com/_i1ciq8
11. Extended SSDs are used for
1. total body irradiation
2. large mantle fields
3. treating head and neck cancers: 1&2
12. Bragg peak is:
A An ionization maximum near the end of the range of a heavy charged particle
B A maximum in the curve of activity and time for a patient and daughter
radionuclide in equilibrium
C A maximum concentration of Compton interactions
D The maximum activity of an isotope: A An ionization maximum near the end of the range of a
heavy charged particle
13. Organs that can be affected by motion are the:
1. lung
2. liver
3. pancreas: 1,2,3
14. Which of the following is not used for brachytherapy treatments?
A cesium
B cobalt
C iodine
D iridium: B cobalt
15. The BAT system uses __________ energy to localize the treatment target.
A x-ray
B microwave
C radiofrequency
D ultrasound: D ultrasound
16. Which of the following accounts for target motion and uncertainty in posi-
tioning?
A GTV
