Dose 2016

Tissue and Phantom Material Characterization -as used in Oncentra MP-

Composition

H

H

ρ

ρ

elec

mass

DCM

ρ

ρ

elec,H O

mass,H O

2

2

A ir (ou tside patient)

0 .00121

0 .00109

-992

-128

A ir (inside pa tien t) • 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 ” 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

Quality of conversion affects dose calculation - one of the weakest links in the calculation chain!