Radiation Therapy Phantom Research Articles

Anthropomorphic radiation therapy phantoms: A quantitative assessment of tissue substitutes

Compositional analyses of samples of soft tissue and lung substitutes used in the construction of anthropomorphic radiotherapy phantoms were performed for products from Alderson Research Laboratories Inc., Kyoto Scientific Specimens Company/Capintec Inc., Humanoid Systems Inc., Radiology Support Devices Inc., and The Phantom Laboratory Inc. To assess quality control in the manufacture process, the results of these compositional analyses were compared with individual manufacturer's design specifications and electron densities measured by computed tomography analysis of actual phantom slices. A comparison of the manufacturers design specifications against reference tissue parameters from Tissue Substitutes in Radiation Dosimetry and Measurement (International Commission on Radiation Units and Measurements) indicates marked differences in the basic design of commercially available anthropomorphic phantoms.

Tissue to air ratios for open-cut uranium mine employees: a simulation using circular plane sources

Tissue to air ratios of absorbed dose have been measured for certain organs in an Alderson Rando radiotherapy phantom irradiated by simulated circular plane sources of degraded gamma rays from radium-226. The absorbed dose measurements were performed using thermoluminescent dosemeters. Factors were determined which relate the absorbed dose received by the organ of interest to (i) the absorbed dose in air at the height of the organ, (ii) the adsorbed dose measurement by a personal monitor worn at the chest and waist, and (iii) the absorbed dose in air at 1 m above the source. Effective dose equivalents have been calculated using the above factors in conjunction with ICRP 26 weighting factors. The results indicate that a good estimate of the effective dose equivalent can be obtained irrespective of the wearing position of the personal monitor on the trunk.

メタアクリル酸メチル樹脂(アクリライト)の人体フアントームとしての適用性にについて(コバルト60γ線に対する)

We discussed on the applicability of Acrylite as a body phantom in deep radiotherapy in the previous report, and now reported in telecobalt therapy in this paper. We measured the attenuation curves and percentage depth dose curves of various field sizes in water and Acrylite. The total linear absorption coefficient of Co^<60> gamma rays in Acrylite was 1.17 times greater than that in water in proportion of their electron densities, e.g.the mass absorption coefficients of both materials coincided each other practically. On the otherhand, the ratio of depths giving the same depth doses was about 1.1,which was lower than the ratio of the absorption coefficient, and was dependent on the field size in some degree. While they were somewhat different in the state of the scatter, Acrylite was available practically to the phantom in consideration that the thickness of Acrylite multiplied by 1.1 was equivalent to that of water. The dosage at the rotation centre in the human pelvis was measured and compared with the calculated one by the Quimby's method using the depth dose data in water and Acrylite. Then the effective body contour as Acrylite was determined by the transit dose measurement. Absorption and scatter in the human pelvis as whole was closer to Acrylite than water, and Acrylite was able to use as pelvic phantom as it was.