418-419 / 2239
Composition
2
mass
mass,H O
ρ
ρ
2
elec
elec,H O
ρ
ρ
H
DCM
H
A ir (ou tside patient)
0 .00121
0 .00109
-992
-128
A ir (inside pa tien t)
0 .00121
0 .00109
-976
-127
Lung (ICRU 44 )
0 .50
0 .50
-480
-96
Ad ipose (ICRU 44 )
0 .95
0 .95
-96
-72
Muscle (ICRU 44 )
1 .05
1 .04
48
-63
Ca rtilage (ICRP 23 )
1 .10
1 .08
128
-58
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?
………
2 /3 Ca rtilage , 1/3 Bone
1 .35
1 .29
528
-33
1 /3 Ca rtilage , 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 A lum inum
2 .40
2 .15
2224
73
A lum inum
2 .70
2 .34
2640
99
A lum inum
2 .83
2 .46
2832
111
Iron
7 .87
6 .60
>2832
112
Water
1 .00
1 .00
-
“127 ”
Quality of conversion affects dose calculation
- one of the weakest links in the calculation chain!