Photon Isodose curves Flashcards
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%