TY - JOUR
T1 - Determination of individual S-values for 131I using segmented CT data and the EGS4 Monte Carlo code
AU - Wolf, Ingo
AU - Zankl, Maria
AU - Scheidhauer, Klemens
AU - Vabuliene, Eugenia
AU - Regula, Dieter
AU - Von Schilling, Christoph
AU - Schwaiger, Markus
PY - 2005
Y1 - 2005
N2 - In individual voxel phantoms, which were segmented from whole-body computed tomography (CT) scans, S-values were calculated for 131I using the EGS4 Monte Carlo code and compared to Medical Internal Radiation Dose (MIRD) S-values, which were derived from transport calculations in idealized mathematical phantoms. The individually calculated S-values agree very well with the MIRD values for organs, which are source and target simultaneously, when individual organ-mass corrections are applied to the MIRD values. For different source-target combinations, large deviations up to 184% were found. The contribution of the gamma-absorbed fractions to the total dose, however, is small (∼4%). We conclude, therefore, that individual transport calculations in radionuclide-targeted therapies are not necessary for macroscopic dose estimates. Reliable dosimetry is reduced to the problem of accurate activity determination in vivo.
AB - In individual voxel phantoms, which were segmented from whole-body computed tomography (CT) scans, S-values were calculated for 131I using the EGS4 Monte Carlo code and compared to Medical Internal Radiation Dose (MIRD) S-values, which were derived from transport calculations in idealized mathematical phantoms. The individually calculated S-values agree very well with the MIRD values for organs, which are source and target simultaneously, when individual organ-mass corrections are applied to the MIRD values. For different source-target combinations, large deviations up to 184% were found. The contribution of the gamma-absorbed fractions to the total dose, however, is small (∼4%). We conclude, therefore, that individual transport calculations in radionuclide-targeted therapies are not necessary for macroscopic dose estimates. Reliable dosimetry is reduced to the problem of accurate activity determination in vivo.
KW - Dosimetry
KW - Individual phantoms
KW - Medical Internal Radiation Dose (MIRD)
KW - Radionuclide therapy
UR - http://www.scopus.com/inward/record.url?scp=16444373498&partnerID=8YFLogxK
U2 - 10.1089/cbr.2005.20.98
DO - 10.1089/cbr.2005.20.98
M3 - Article
C2 - 15778588
AN - SCOPUS:16444373498
SN - 1084-9785
VL - 20
SP - 98
EP - 102
JO - Cancer Biotherapy and Radiopharmaceuticals
JF - Cancer Biotherapy and Radiopharmaceuticals
IS - 1
ER -