The Effect of Imaging Modality (magnetic Resonance Imaging Vs. Computed Tomography) and Patient Position (supine Vs. Prone) on Target and Organ at Risk Doses in Partial Breast Irradiation.

Conventionally computed tomography (CT) has been used to delineate target volumes in radiotherapy; however, magnetic resonance imaging (MRI) is being continually integrated into clinical practice; therefore, the investigation into targets derived from MRI is warranted. The purpose of this study was to evaluate the impact of imaging modality (MRI vs. CT) and patient positioning (supine vs. prone) on planning target volumes (PTVs) and organs at risk (OARs) for partial breast irradiation (PBI).