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Positioning for spine SBRT
BodyFIX and Hexapod 6DOF table, Elekta CBCT.
(42 spine patients)
Small positioning errors after the initial CBCT
setup were observed, with 90% within 1 mm
and 97% within 1
°
(after 10
±
3 min.).
Only half of patients within tolerance (1 mm
and 1
°
) for the entire treatment (63
±
4
min).
With intra-fraction IGRT every 15-20 min and
using a 1-mm and 1 correction threshold, the
target was localized to within 1.2 mm and
0.9
°
with 95% confidence.
Hyde IJROBP 82, 2012 e555
intrafractional imaging and corrections needed approximately every 15 to 20 min.