TABLE 1.

Relative Differences Between VSV and Direct MC Approaches for ⁹⁰Y and ¹³¹I on 20 Spheres

			Percentage of relative differences between approaches
	Sphere radius			¹³¹I
Voxel size (cm)	Pixels	Centimeters	⁹⁰Y	Electrons	Photons	Total
0.38	4	1.52	0.42	0.54	0.04	0.50
	8	3.04	0.49	0.51	−1.10	0.29
	16	6.08	1.00	0.49	−1.29	0.06
	32	12.16	1.01	0.45	−1.26	−0.20
	64	24.32	1.02	0.44	−1.10	−0.35
0.48	4	1.92	0.25	0.31	−0.28	0.26
	8	3.84	0.26	0.28	−1.40	−0.01
	16	7.68	0.17	0.23	−1.80	−0.36
	32	15.36	0.06	0.20	−1.81	−0.66
	64	30.72	−0.07	0.19	−1.40	−0.69
0.53	4	2.12	0.22	0.24	−0.56	0.16
	8	4.24	0.19	0.20	−1.57	−0.12
	16	8.48	0.08	0.15	−2.01	−0.51
	32	16.96	−0.03	0.12	−2.00	−0.84
	64	33.92	−0.17	0.11	−1.90	−1.02
0.77	4	3.08	0.02	0.06	−0.03	0.05
	8	6.16	−0.04	0.01	−1.72	−0.41
	16	12.32	−0.18	−0.05	−2.18	−0.87
	32	24.64	−0.32	−0.07	−2.09	−1.12
	64	49.28	−0.32	−0.08	−2.11	−1.30
Average			0.20	0.22	−1.38	−0.36
SD			0.41	0.19	0.69	0.51