362-363 / 1245
Composition
2
mass
mass,H O
2
elec
elec,H O
H
DCM
H
Air (outside patient)
0.00121
0.00109
-992
-128
Air (inside patient)
0.00121
0.00109
-976
-127
Lung (ICRU 44)
0.50
0.50
-480
-96
Adipose (ICRU 44)
0.95
0.95
-96
-72
Muscle (ICRU 44)
1.05
1.04
48
-63
Cartilage (ICRP 23)
1.10
1.08
128
-58
2/3 Cartilage, 1/3 Bone
1.35
1.29
528
-33
1/3 Cartilage, 2/3 Bone
1.60
1.52
976
-5
Bone (ICRP 23)
1.85
1.72
1488
27
Bone (ICRP 23)
2.10
1.95
1824
48
½ Bone, ½ Aluminum
2.40
2.15
2224
73
Aluminum
2.70
2.34
2640
99
Aluminum
2.83
2.46
2832
111
Iron
7.87
6.60
>2832
112
Water
1.00
1.00
-
“127”
Tissue and Phantom Material Characterization
-as used in Oncentra MP-
• how many linear segments should be used?
• which tissue-equivalent materials are suitable for calibration?
• where should the boundaries between tissue types be set?
………
Quality of conversion affects dose calculation
- one of the weakest links in the calculation chain!