Table 7.

The distance between the BB center and the isocenter after couch pitch and roll positioning

	Distance (mm)
	No Weight				With Weight (13.8 kg)
Pitch/Roll	MV AP		KV RT Lat		MV AP		KV RT Lat
$0^{°}/0^{°}$	0.0	0.0	0.0	L 0.3	S 0.1	0.0	S 0.1	0.0
$+3^{°}/+3^{°}$	I 0.2	L 0.2	0.0	L 0.4	0.0	L 0.4	I 0.2	0.0
$-3^{°}/-3^{°}$	S 0.1	R 0.1	0.0	0.0	S 0.3	R 0.3	S 0.5	0.0
$0^{°}/0^{°}$	0.0	0.0	0.0	L 0.2	S 0.1	0.0	S 0.1	L 0.2

$\mathrm{I}=\text{inferior}$; $\mathrm{S}=\text{superior}$; $\mathrm{L}=\text{left}$; $\mathrm{R}=\text{right}$; $\mathrm{I} 0.2=\text{the BB was} 0.2 \text{mm}$ inferiorly from the isocenter.