Amersham model 6702 Dosimetry Datasets

Note: The following tables are adapted from Rivard et al., Med. Phys. 31, 633-674 (2004).

Table I. NIST standard WAFAC calibration dates for air kerma strength for each manufacturer, and dose rate constant values. Note that for a given source type, the % change in Λ from the 1999 value is different for different seed models.

Manufacturer Source Type NIST date used by ADCL
and NIST as standard
consensusΛ
[cGy -h·-1·U-1]
% difference in Λ
from 1999 value
Amersham model 6702 125I April 15, 1998 1.036 N/A

Table II.Consensus g(r) values

r[cm] 0.10 0.15 0.25 0.50 0.75 1.00 1.50 2.00
Line source
approximation L=3.0 mm
1.020 1.022 1.024 1.030 1.020 1.000 0.935 0.861
Point source
approximation
0.673 0.809 0.929 1.008 1.014 1.000 0.939 0.866

 

r[cm] 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00
Line source
approximation L=3.0 mm
0.697 0.553 0.425 0.322 0.241 0.179 0.134 0.0979
Point source
approximation
0.702 0.557 0.428 0.324 0.243 0.180 0.135 0.0986

Interpolated data are boldface, and italicized data are non-consensus data obtained from candidate datasets.

Table III. F(r,θ)

Polar angleθ (degrees)

    0 5 10 15 20 30 40 50 60 70 80 Φan(r)
r [cm] 0.5 0.385 0.413 0.531 0.700 0.788 0.892 0.949 0.977 0.989 0.996 1.000 0.986
  1 0.420 0.472 0.584 0.700 0.789 0.888 0.948 0.973 0.985 0.992 0.998 0.960
  2 0.493 0.546 0.630 0.719 0.793 0.888 0.944 0.967 0.983 0.990 0.998 0.952
  3 0.533 0.586 0.660 0.738 0.805 0.891 0.944 0.967 0.983 0.990 0.998 0.951
  4 0.569 0.613 0.681 0.749 0.810 0.892 0.944 0.967 0.983 0.990 0.998 0.954
  5 0.589 0.631 0.697 0.758 0.814 0.892 0.944 0.967 0.983 0.990 0.998 0.954

Table IV. Dose rates (cGy h-1 U-1) as a function of distance for Amersham model 6702 brachytherapy sources using the 1-D dosimetry formalism of Eq. (11) with interpolation for gL(r) and fan(r).

r (cm) 0.5 1.0 1.5 2.0 3.0 4.0 5.0 6.0 7.0
  4.119 0.995 0.413 0.213 0.0768 0.0344 0.0169 0.00890 0.00490