Figure 6.

Comparisons of $J_m^{+}$ ((a) and (c)) and φ_x ((b) and (d)) between the Monte Carlo method and SP_N approximations in phantoms containing high absorption and void-like inclusions. μ_a, μ_s, g, and n_b of the surrounding continuous volume of the phantom are fixed to 0.05 mm⁻¹, 5.0 mm⁻¹, 0.9, and 1.33, respectively. μ_a and μ_s of the small cylindrical inclusion are set to 0.25 mm⁻¹ and 5.0 mm⁻¹ (high absorption), and 0.005 mm⁻¹ and 0.1 mm⁻¹ (void-like), respectively. The modulation frequency is 100.0 MHz. The display settings are the same as those in figure 2.