Evaluation of safety margins for cone beam CT-based adaptive prostate radiotherapy

External beam radiotherapy treatment delivery entails uncertainties [1,2] that can affect the coverage of the target and therefore the treatment outcome [3,4]. In order to account for them, a margin is added to the clinical target volumes (CTV) to create planning target volumes (PTV). This margin depends on the uncertainties that we are dealing with, and can be computed using safety margin recipes, for instance the so-called Van Herk formula [5]. This recipe is based on the separation of systematic uncertainties, that affect the treatment as a whole, and the random uncertainties, that affect each fraction independently.
Source: Physica Medica: European Journal of Medical Physics - Category: General Medicine Authors: Tags: Original paper Source Type: research