Realistic reference adult and paediatric phantom series for internal and external dosimetry

Abstract

A new generation of realistic, image-based anthropomorphic phantoms has been developed based on the reference masses and organ definitions given in the International Commission on Radiological Protection Publication 89. Specific absorbed fractions for internal radiation sources have been calculated for photon and electron sources for many body organs. Values are similar to those from the previous generation of 'stylized' (mathematical equation-based) models, but some differences are seen, particularly at low particle or photon energies, due to the more realistic organ geometries, with organs generally being closer together, and with some touching and overlapping. Extension of this work, to use these phantoms in Monte Carlo radiation transport simulation codes with external radiation sources, is an important area of investigation that should be undertaken.

Figure 1.

Stylised adult male model of Snyder et al.⁽¹⁾ showing (a) exterior view, (b) skeleton and internal organs.

Figure 2.

Anterior views of the NURBS models of the adult male (left) and adult female (right).

Figure 3.

Sample images of NURBS standardised models, scaled to the ICRP 89 recommended reference organ masses, developed for internal and external dose assessment: (a) newborn female model, (b) 15-y-old male model.

Figure 4.

Sample photon SAF plot, showing comparison of NURBS model values (diamonds) with values from the Cristy/Eckerman stylised series (squares): Adult male (liver←liver).

Figure 5.

Sample photon SAF plot, showing comparison of NURBS model values (diamonds) with values from the Cristy/Eckerman stylised series (squares): Adult male (lungs←liver).

Figure 6.

Sample photon SAF plot, showing comparison of NURBS model values for different reference age models: males, (kidneys ← liver).

Figure 7.

Electron absorbed fractions in the kidneys of the adult female, kidneys as a target (diamonds) and liver as a target (squares).

Figure 8.

Electron absorbed fractions in the testes of the newborn male.