ESTRO 37 Abstract book

Results All positioning errors were small, we found smaller errors for the Encompass/Hexapod combination after set-up correction and after treatment. Intra fraction movement was smaller for the BrainLab system. Overall rotations errors are smaller because of the use of the Hexapod couch (due to the 6D corrections). Results are shown in the Table. After Setup (AS) correction; After Radiation (AR); Intrafraction Movement (IM) Conclusion Both systems demonstrated sub millimetre accuracy. Differences are small and not clinically relevant. The newly adopted procedure is safe. 1. Int. J. Radiation Oncology Biol. Phys., 2008; 72;1:261– 267

Rotations AR [º]

Translations AR [mm]

Rotations AS [º]

Rotations IM [º]

Translations AS [mm]

Translations IM[mm]

X

Y

Z

X

Y

Z

X

Y

Z

X

Y

Z

X

Y

Z

X

Y

Z

Brainlab- mask with Exactrac Mean of means

0.13

-0.03 -0.02

-0.02 0.06

0.01

-0.01 -0.02 -0.39

0.04 0.02 0.02

-0.04 0.05 -0.45

-0.03 0.07 -0.11

Stdev mean Mean stdev

of

0.10

0.25 0.17 0.49

0.47 0.52 0.25

0.38

0.22 0.40

0.46 0.49 0.16

0.13

0.06 0.11

0.15

0.17

of

0.30

0.35 0.29 0.39

0.43 0.39 0.44

0.52

0.42 0.35

0.42 0.46 0.29

0.30

0.21 0.14

0.15

0.27

Qfx-mask with Hexapod Mean

of

0.01

0.10 -0.10

-0.03 0.00

0.01

-0.01 -0.04 -0.02

-0.10 0.02 0.05

-0.03 -0.13 0.10

-0.08 0.01 -0.04

means Stdev mean Mean stdev

of

0.09

0.17 0.08 0.12

0.20 0.06 0.19

0.33

0.13 0.14

0.16 0.23 0.17

0.26

0.12 0.09

0.22

0.20

of

0.15

0.21 0.15 0.13

0.13 0.13 0.27

0.32

0.19 0.17

0.18 0.32 0.24

0.30

0.18 0.17

0.17

0.31