Prophylactic cranial irradiation for ALL is administered to a total dose of:
A. 1200 cGy
B. 1800 cGy
C. 3000 cGy
D. 4500 cGy
E. 6000 cGy correct answers B. 1800 cGy
The treatment time for a field requiring 350 monitor units while the linear acellerator dose rate is
220 units/minute is:
A. .394 minutes
B. .629 minutes
C. 1.59 minutes
D. 2.52 minutes correct answers C. 1.59 minutes
Placing marks on the central axis only is:
A. Sufficient for daily realignment and targeting
B. Sufficient when target margins are small
C. Adequate for treating small fields
D. Insufficient for daily realignment and targeting correct answers D. Insufficient for daily
realignment and targeting
*Marks should be placed on the central axis and along coordinate planes to assure the patient and
location target is accurately reproduced.
,During total CNS irradiation, the patient is:
A. Supine with an extended chin
B. Supine with chin flexed
C. Prone with chin slightly extended
D. Prone with chin flexed correct answers C. Prone with chin slightly extended
Electron contamination from high energy photon beams may result from photon interactions with
the:
A. Room air
B. Collimators
C. Bolus
D. Lucite trays correct answers B. Collimators
Lucite is often used as the material for positioning devices. One major concern when this
material is in the path of the treatment beam is:
A. Electron contamination
B. Beam attenuation
C. Decreased rigidity
D. Acquired radioactivity correct answers B. Beam attenuation
Advantages of networked digital image management do not include:
A. Dispersed access to images
B. Multiple users can share images
,C. Physical storage space is minimized
D. Computer disk space is not an issue correct answers D. Computer disk space is not an issue
In the treatment of seminoma, an external testicular shield should be used for the remaining
testicle. This is Important since the TD 5/5 for the testis is as low as:
A. 1 Gy
B. 10 Gy
C. 20 Gy
D. 40 Gy correct answers A. 1 Gy
Which of the following cannot produce a 3 dimensional image?
A. MRI
B. CT
C. Ultrasound
D. Electronic portal imaging correct answers D. Electronic portal imaging
A procedure in which an implant is made using a trocar, with radioactive sources introduced into
the trocar and then the trocar is removed is called:
A. Self-attenuation
B. Interstitial preloading
C. Intracavitary microloading
D. Interstitial afterloading correct answers D. Interstitial afterloading
The precise daily reproduction of patient position depends on:
, 1. Patient age
2. Type of treatment machine
3. Anatomical site treated
4. Patients overall health
A. 1 & 2
B. 2 & 3
C. 3 & 4
D. 1 & 4 correct answers C. 3 & 4
The linear scales on the treatment table are used as an aid for:
A. Translation of patient position on the table
B. Verifying filament voltage
C. Verifying gantry readout accuracy
D. Documentation of treatment dose correct answers A. Translation of patient position on the
table
Compared to water, the density of bone is:
A. 1.00
B. 1.65-1.85
C. 0.33-0.35
D. 0.2-0.26 correct answers B. 1.65-1.85
If the width of the vertebral body is 5.3 cm and measures 7.5 cm on the portal verification film,
the magnification factor is: