Evaluation of Atlas-Based Auto-Segmentation and Deformable Propagation of Organs-at-Risk for Head-and-Neck Adaptive Radiotherapy

摘要

Purpose: Evaluate the accuracy of atlas-based auto-segmentation and intra-patient deformable propagation of organs-at-risk (OARs) on CT and CBCT for head-and-neck (HN) adaptive radiotherapy (ART).Methods and Materials: Six patients were included in this study. Three images of each patient were selected: a pre-treatment planning CT, an in-treatment planning CT and a CBCT. The selected in-treatment planning CT and CBCT were acquired on the same day (i.e., treatment day 22nd), and typically within a 1-2 hour time interval. Seven OARs were manually contoured on the pre-treatment and in-treatment CTs. Manual contours on the in-treatment CT were copied onto the CBCT using local rigid-body registration due to the inherent inferior image quality of CBCT.