Advanced Physics for Brachytherapy 2018

Geometrical uncertainties in brachytherapy

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Reconstruction uncertainties

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Specification of sources relative to anatomy

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Equivalent to EBRT set-up uncertainties

• Internal movement (relative to applicator)

© K Tanderup

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Target: depends on applicator

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Intracavitary cervix BT: applicator moves with cervix?

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Prostate (and breast) needle implant: movement along needles

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OAR: volume and location changes relative to BT implant

• Translating geometric uncertainties to dosimetric uncertainties for D 90 target, D 2cm³ OAR

Hoskin et al 2003, R&O 68