Table 6.

Summary of the individual and cumulative systematic and random uncertainties for the different components of the SRS/SRT treatment with the Brainlab ExacTrac system.

Uncer.	SRS/SRT Equipment	Type	Lat (mm)	Long (mm)	Vert (mm)	Roll (o)	Pitch (o)	Yaw (o)	Rad (mm)
${\mathrm{\Delta }}_{\mathrm{M}}$	Mask	Systematic	Depends on the mask manufactured for each patient as shown in Fig. 1.
${\sigma }_S$	Setup	Random	Standard Deviation of Mean Quad Sum XC
${\mathrm{\Delta }}_{\mathrm{F}}$	Frame	Systematic	0.18	$0.25\hspace{0.17em}p=0.01$	$-1.27\hspace{0.17em}p=0.17$	$0.32\hspace{0.17em}p=0.33$	$0.18\hspace{0.17em}p=0.59$	$0.47\hspace{0.17em}p=0.60$	2.52
${\mathrm{\Delta }}_{\mathrm{L}}$	Localizer	Systematic	$-0.03\hspace{0.17em}p=0.33$	$-0.01$	0.03	$-0.03$	0.00	$-0.01$	0.36
${\sigma }_{\text{XR}}$	X‐ray	Random	0.20	0.18	0.16	0.26	0.20	0.19	0.16
${\mathrm{\Sigma }}_{\text{ISO}-\text{MV}}$	Isocenter of MV beam	Systematic	0.27	0.24	0.34	n/a	n/a	n/a
${\mathrm{\Sigma }}_{\text{ISO}-\text{KV}}$	Isocenter of kV imager	Systematic	0.15	$-0.40$	0.21	n/a	n/a	n/a
${\mathrm{\Sigma }}_{\text{ISO}-\text{IR}}$	Isocenter of IR system	Systematic	0.02	0.02	0.02	0.01	0.01	0.01
${\mathrm{\Delta }}_{\mathrm{C}}$	Couch sag	Systematic	0.85	0.01	$-0.68$	$-0.10$	0.20	n/a	1.09