Organ dose conversion coefficients on an ICRP-based Chinese adult male voxel model from idealized external photons exposures

2009 ◽  
Vol 54 (21) ◽  
pp. 6645-6673 ◽  
Author(s):  
Liye Liu ◽  
Zhi Zeng ◽  
Junli Li ◽  
Rui Qiu ◽  
Binquan Zhang ◽  
...  
2017 ◽  
Vol 58 (5) ◽  
pp. 737-744 ◽  
Author(s):  
Wei Lv ◽  
Hengda He ◽  
Qian Liu

Abstract For evaluating radiation risk, the construction of anthropomorphic computational phantoms with a variety of physiques can help reduce the uncertainty that is due to anatomical variation. In our previous work, three deformable Chinese reference male phantoms with 10th, 50th and 90th percentile body mass indexes and body circumference physiques (DCRM-10, DCRM-50 and DCRM-90) were constructed to represent underweight, normal weight and overweight Chinese adult males, respectively. In the present study, the phantoms were updated by correcting the fat percentage to improve the precision of radiological dosimetry evaluations. The organ dose conversion coefficients for each phantom were calculated and compared for four idealized external photon exposures from 15 keV to 10 MeV, using the Monte Carlo method. The dosimetric results for the three deformable Chinese reference male phantom (DCRM) phantoms indicated that variations in physique can cause as much as a 20% difference in the organ dose conversion coefficients. When the photon energy was <50 keV, the discrepancy was greater. The irradiation geometry and organ position can also affect the difference in radiological dosimetry between individuals with different physiques. Hence, it is difficult to predict the conversion coefficients of the phantoms from the anthropometric parameters alone. Nevertheless, the complex organ conversion coefficients presented in this report will be helpful for evaluating the radiation risk for large groups of people with various physiques.


2009 ◽  
Vol 54 (21) ◽  
pp. 6675-6690 ◽  
Author(s):  
Liye Liu ◽  
Zhi Zeng ◽  
Junli Li ◽  
Binquan Zhang ◽  
Rui Qiu ◽  
...  

2011 ◽  
Vol 148 (1) ◽  
pp. 9-19 ◽  
Author(s):  
X. Zhang ◽  
X. Xie ◽  
J. Cheng ◽  
J. Ning ◽  
Y. Yuan ◽  
...  

Author(s):  
Fangfang Liu ◽  
Mingqi Shen ◽  
Taosheng Li ◽  
Chunyu Liu

In order to calculate the dose conversion coefficients for proton, the voxel model of Chinese Reference Adult Woman (CRAW) was established by the Monte Carlo transport code FLUKA according to the Chinese reference data and the Asian reference data. Compared with the reference data, the deviations of the mass for organs or tissues of CRAW is less than ±5%. Calculations have been performed for 14 incident monoenergetic protons energies from 0.02GeV to 10TeV at the irradiation incident of anterior-posterior (AP) and posterior-anterior (PA). The results of fluence-to-effective dose conversion coefficients are compared with data from the different models such as an anthropomorphic mathematical model, ICRP reference adult voxel model, the voxel-based visible Chinese human (VCH). Anatomical differences among various computational phantoms and the spatial geometric positions of the organs or tissues lead to the discrepancies of the effective dose conversion coefficients in the ranging from a negligible level to 107% at proton energies below 0.2GeV. The deviations of the coefficients, above 0.2GeV, are mostly within 10%. The results of fluence-to-organ absorbed dose conversion coefficients are compared with the data of VCH. The deviations of the coefficients, below and above 0.2GeV, are within 150% and 20%, respectively. The primary factors of the deviations for the coefficients should be due to the differences of the organ mass and the size of the body shape.


2013 ◽  
Vol 84 (2) ◽  
pp. 246-253 ◽  
Author(s):  
Hui Theng Chong ◽  
Kim Wei Thea ◽  
Joseph Descallar ◽  
Yong Chen ◽  
Oyku Dalci ◽  
...  

ABSTRACT Objective: To compare the esthetic preference of White and Chinese judges with regard to Chinese lip position. Materials and Methods: The profile images of a dental and skeletal Class I Chinese adult male and female were digitally adjusted to Chinese mean values. The lip profile was adjusted with the upper and lower lip at the mean distance from the Ricketts' E-line. These images were used as baseline images and were further digitally manipulated to generate six additional images with the upper and lower lip such that they lay 0.5, 1.0, and 2.0 standard deviations (SDs) in front of or behind the E-line. An additional image was modified based on a White mean value. The images were viewed and ranked by 251 White and Chinese judges (dentists and laypersons) in Australia and China. Results: Significantly more Chinese judges ranked the retrusive profiles higher than the White judges. The White judges also ranked the profile image adjusted to −0.5 SD as the most esthetic for both the female and male, while the Chinese judges ranked the −1.0 SD profile as the most esthetic. Conclusions: The ethnicity of the judges is a significant factor influencing the perception of esthetic lip position. The Chinese judges prefer a more retrusive profile and are more likely to rate a protrusive profile as unacceptable, compared with the White judges.


2015 ◽  
Vol 57 (2) ◽  
pp. 182-188 ◽  
Author(s):  
Xiaomin Zhang ◽  
Xiangdong Xie ◽  
Decheng Qu ◽  
Jing Ning ◽  
Hongmei Zhou ◽  
...  

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