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Phantoms for TPS verification and plan QA: solid plastic slabs
Advantages
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Robust
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Allow easy, quick and reproduceable setup
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Can be used with non water-proof detectors
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Easier to use with films
Disadvantages
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Water-equivalence depends on modality and
energy (MV, kV, MeV)
•
Expensive if manufactured to be water-
equivalent
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Different samples of same type of plastic could
vary in composition and from manufacturer
specification
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Possible degradation with time
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Possible charge storage effects