Treated volume

 This is the volume of tissue that is planned to receive a specified dose and is enclosed by the isodose surface corresponding to that dose level, e.g. 95 per cent. The shape, size and position of the treated volume in relation to the PTV should be recorded to evaluate and interpret local recurrences (in field versus marginal) and complications in normal tissues, which may be outside the PTV but within the treated volume.

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