Beam-on time and Treatment time analysis
Beam-on time was collected from Eclipse and RefleXion X1 TPS and
compared. Total treatment time from imaging to end of treatment session
was recorded using Aria offline review for Eclipse VMAT plans for every
fifth fraction for each patient. Institutional guidelines for VMAT CSI
treatment include imaging all isocenters separately using kV/kV
orthogonal pairs, shifting and adjusting positioning to obtain an
accurate match for each isocenter position. CBCT is used for the first
fraction and every 5th fraction or if alignment is problematic. After
the imaging and adjustments, each isocenter position is confirmed with
planar MV port added to the arc to confirm the accuracy of the shifts.