Folie 1

Some Concluding Remarks

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In radiosurgery often 0-mm margins are being advocated

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There will always be residual geometrical uncertainties

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Target definition

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Errors in image-guidance systems

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Indirect measures of tumor position

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Always verify the margin algorithm used in the Treatment Planning System

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3D margin algorithm (and not 2D)

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What is the resolution of the margin algorithm (e.g. CT resolution?)

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Verify that margin are not truncated to voxel positions, especially in

the superior-inferior direction