Photon Isodose curves Flashcards Preview

Radiation Oncology Phase 1 RANZCR > Photon Isodose curves > Flashcards

Flashcards in Photon Isodose curves Deck (5)
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1
Q
For 6MV photon beam (All questions for 10x10cm field):
SD
DMax
D90
D50
D20 (if possible)
Dose at 10cm
A
SD = 30%
Max = 1.5cm
D90 = 4.5cm
D50 = 16cm
D20 = 30cm

Dose at 10cm = 69%

2
Q
For 4MV photon beam (All questions for 10x10cm field):
SD
DMax
D90
D50
D20 (if possible)
Dose at 10cm
A
SD = 40%
Max = 1 cm
D90 = 3.5cm
D50 = 14.5cm
D20 = ?27cm

Dose at 10cm = 65%

3
Q
For 10MV photon beam (All questions for 10x10cm field):
SD
DMax
D90
D50
D20 (if possible)
Dose at 10cm
A
SD = 15%
Max = 2.5 cm
D90 = 4.5cm
D50 = 18cm
D20 = guess around 33cm

Dose at 10cm = 73%

4
Q
For 18MV photon beam (All questions for 10x10cm field):
SD
DMax
D90
D50
D20 (if possible)
Dose at 10cm
A
SD = 10%
Max = 3.5 cm
D90 = 7cm
D50 = 20.5cm
D20 = ?36cm

Dose at 10cm = 80%

5
Q
For Co-60 photon beam (80cm SSD, 10x10cm field):
SD
DMax
D90
D50
D20 (if possible)
Dose at 10cm
A
SD = 50%
Max = 0.5cm
D90 = 2.5cm
D50 = 11.5cm

Dose at 10cm = 56%