Table 5.

Dosimetric and geometrical parameters used for ${\mathrm{D}}_{\text{iso}}$ reconstruction.

Beam	Gantry Angle	$\rho (g/c{m}^3)$	$\hspace{0.17em}\rho iso(g/c{m}^3)$	z (cm)	$z_{iso}(cm)$	w (cm)	$w_{iso}(cm)$	L (cm)	$D_{iso,TPS}(cGy)$	$D_{iso}(cGy)$
1	0°	0.926	0.961	23.4	16.6	21.7	16.0	9.5	128	$126.0\pm 3.0$
2	130°	0.921	1.050	23.4	10.5	21.6	11.0	9.5	82	$82.8\pm 1.5$
3	200°	0.947	0.785	25.2	7.2	23.9	5.7	8.8	66	$64.1\pm 1.1$

Notes: ρ and ${\rho }_{\text{iso}}$ are the physical density along beam axis across the patient and up to isocenter, respectively; z and ${\mathrm{z}}_{\text{iso}}$ are the geometrical patient thickness and the isocenter depth along beam axis; w and ${\mathrm{w}}_{\text{iso}}$ are the radiological paths along the beam axis; L is the equivalent square field size, ${\mathrm{D}}_{\text{iso},\text{TPS}}$ is the calculated dose by TPS at isocenter and ${\mathrm{D}}_{\text{iso}}$ is the mean measured dose.