FIGURE 5. Electron absorbed fractions for self-irradiation of TAM within femoral head of 51-y-old man. Three dosimetry methodologies are compared. Method of Bouchet et al. (27,28) assumes that TAM self-absorbed fractions are equal to TMS self-absorbed fractions, whereas method of Eckerman and Stabin (15) scales TMS self-absorbed fractions by reference cellularity factor (0.25 for femoral head). TAM self-absorbed fractions reported in this study are calculated directly using macrostructural transport model of EGS4 transport code (solid line, no data points). Dashed lines indicate potential variations in absorbed fraction with changes in individual marrow cellularity either lower than that of reference man (10%) or higher than that of reference man (40%).