RAD 2652 PRE

If a patient tumor receives a dose of 250 cGy/day at 79.9% PDD, what is the dose at dmax for this treatment?
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If a patient tumor receives a dose of 250 cGy/day at 79.9% PDD, what is the dose at dmax for this treatment?
313 cGy ??????
Voxels represent:
a volume of tissue within a patient
The prostate treatment plan that would yield a better DVH is:
A) 7 field IMRT with 6 MV
B) Single field with 10 MV
C) AP/PA fields with 10 MV
D) 7 field with 6 MeV
A) 7 field IMRT with 6 MV
A treatment dose to a single PA spine field using 6 MV at 200 cGy/fx; field size 8x8 cm; treatment depth of 5 cm; is to be calculated. What other factors are needed to perform the calculation to determine the correct monitor units?
A?) SSD or SAD (?)
B) TMR
C) BSF and output
D) PDD and output
A) SSD/SAD (answer was cut off)
To determine the monitor units for an irregular field, such as an 8x19 rectangular field, which formula is used to adjust the field size in order to select the correct factors in the dose calculation?
A) Inverse Square
B) Equivalent Square
C) Mayneord's Factor
D) Scatter-Air-Ratio
B) Equivalent Square
An AP/PA lung treatment plan yields a spinal cord dose of 5500 cGy. As a dosimentrist, you should:
A) Submit the plan for approval
B) Modify the plan by adding a 60 degree wedge to the AP field
C) Modify the plan by changing the field weighting
D) Modify the plan by adding two lateral fields
C Beam weighting
What is the effects when using a 1.0 cm bolus on a tangential chestwall site?
A) The dose will increase 1.0 cm below the skin surface, sparing the skin.
B) The dose will be uneven below the skin surface; no change in skin sparing
C) The dose will be greater at the surface, no skin sparing
C) The dose will be greater at the surface, no skin sparing
When setting the treatment field with the isocenter at 100 cm, the patient's lateral SSD reading is 80 on the right lateral and 81 on the left lateral. What is the patient's interfield measurement?
A) 36 cm
B) 37 cm
C) 38 cm
D) 39 cm
D) 39 cm ((SAD-80) + (SAD-81))
Which of the following applies to "absorbed dose"?
A) BSF
B) Roentgen
C) Gray
D) TAR
C) Gray
Three (3) dimensional planning requires all of the following EXCEPT:
A) CT Images
B) XYZ coordinates
C) Dwell positions
D) 3 level contour
C) Dwell positions
The regional lymph nodes in breast cancer are: A) The internal mammary, supraclavicular and axillary B) ? C) The internal mammary, supraclavicular, and inguinal D) The internal mammary, supraclavicular, and aorticA) The internal mammary, supraclavicular and axillaryA lung boost is often delivered via: A) Opposed lateral fields B) Opposed oblique fields C) Single oblique fields D) Opposed anterior-posterior fields, and an oblique electron fieldB) Opposed oblique fieldsThe formula for field divergence, shown here, is used to determine the number of degrees that the _________________. tan^-1 = Half cranial field length/SSD A) Couch must rotated for craniospinal field B) Collimator must be turned for a craniospinal field C) Collimator is turned for a 3 field breast treatment D) Couch angle must be turned for a 2 field treatmentA) Couch must rotated for craniospinal fieldA boost dose is to be delivered to a soft tissue sarcoma tumor bed at a depth of 3 cm, the prescription states that 200 cGy/fx be given to the 90% isodose line. The appropriate electron energy used in this case would be? A) 10 MeV B) 12 MeV C) 13 MeV D) 18 MeVB) 12 MeV (E/4 = depth of the 90% isodose line)A suitable wedge angle for two fields separated by 90 degrees is: A) 15 B) 30 C) 45 D) 60C) 45 degrees (Wedge = (180-Hinge)/2)A target volume that includes the CTV with additional margin of 0.5 cm to allow for patient movement and setup error is termed the A) GTV B) CTV C) ITV D) PTVD) PTVAn advantage of SAD setup techniques verses SSD setup techniques is: A) The gantry remains at 90 degrees B) Patients do not have to be moved between gantry angles C) Patients are moved between changes in gantry angles D) The gantry remains at 180 degreesB) Patients do not have to be moved between gantry anglesTAR at the depth of Dmax corrrects for scatter of dose which is the same as: A) SAR B) TPR C) BSF D) PPDC) BSFTD 5/5 means: A) 5% change of complications at 5 Gy B) 5% of complications in 5 out of 5 patients C) 5% chance of complications at 50 cGy D) 5% chance of complications in 5 yearsD) 5% chance of complications in 5 yearsWhen planning a gynecologic implant, the treatment dose is calculated to Point ____ A) A B) B C) C D) DA) A