Building Head and Neck Anatomical Atlas for Robust Image Segmentation using Statistical Models Olivier COMMOWICK, CRL, Childrens Hospital Boston. June 17, 2009. Radiotherapy • Radiotherapy principle: • Use of high energy irradiation beams • Optimize dose on the tumor • Control irradiation of critical structures (OAR)  Need for high precision planning • Irradiation doses computed on each organ • Compare doses with expected levels • Requires delineation of structures 2 Head and Neck Anatomy • Structures of interest • Lymph nodes areas - Separated using visible landmarks - Tumor dissemination regions • Parotids • Spinal cord • Sub-mandibular glands [Grégoire et al., 2003] CT-based delineation of lymph node levels and related CTVs in the node-negative neck : DAHANCA, EORTC, GORTEC, NCIC, RTOG consensus guidelines. Radiotherapy Oncology, 2003. 3 Head and Neck Anatomy • Structures of interest • Lymph nodes areas - Separated using visible landmarks - Tumor dissemination regions • Parotids • Spinal cord • Sub-mandibular glands [Grégoire et al., 2003] CT-based delineation of lymph node levels and related CTVs in the node-negative neck : DAHANCA, EORTC, GORTEC, NCIC, RTOG consensus guidelines. Radiotherapy Oncology, 2003. 3 Head and Neck Anatomy • Structures of interest • Lymph nodes areas - Separated using visible landmarks - Tumor dissemination regions • Parotids • Spinal cord • Sub-mandibular glands [Grégoire et al., 2003] CT-based delineation of lymph node levels and related CTVs in the node-negative neck : DAHANCA, EORTC, GORTEC, NCIC, RTOG consensus guidelines. Radiotherapy Oncology, 2003. 3 Head and Neck Anatomy • Structures of interest • Lymph nodes areas - Separated using visible landmarks - Tumor dissemination regions • Parotids • Spinal cord • Sub-mandibular glands [Grégoire et al., 2003] CT-based delineation of lymph node levels and related CTVs in the node-negative neck : DAHANCA, EORTC, GORTEC, NCIC, RTOG consensus guidelines. Radiotherapy Oncology, 2003. 3 Head and Neck Anatomy • Structures of interest • Lymph nodes areas - Separated using visible landmarks - Tumor dissemination regions • Parotids • Spinal cord • Sub-mandibular glands [Grégoire et al., 2003] CT-based delineation of lymph node levels and related CTVs in the node-negative neck : DAHANCA, EORTC, GORTEC, NCIC, RTOG consensus guidelines. Radiotherapy Oncology, 2003. 3 Head and Neck Anatomy • Structures of interest • Lymph nodes areas - Separated using visible landmarks - Tumor dissemination regions • Parotids • Spinal cord • Sub-mandibular glands [Grégoire et al., 2003] CT-based delineation of lymph node levels and related CTVs in the node-negative neck : DAHANCA, EORTC, GORTEC, NCIC, RTOG consensus guidelines. Radiotherapy Oncology, 2003. 3 Head and Neck Anatomy • Structures of interest • Lymph nodes areas - Separated using visible landmarks - Tumor dissemination regions • Parotids • Spinal cord • Sub-mandibular glands [Grégoire et al., 2003] CT-based delineation of lymph node levels and related CTVs in the node-negative neck : DAHANCA, EORTC, GORTEC, NCIC, RTOG consensus guidelines. Radiotherapy Oncology, 2003. 3 Head and Neck Anatomy • Structures of interest • Lymph nodes areas - Separated using visible landmarks - Tumor dissemination regions • Parotids • Spinal cord • Sub-mandibular glands [Grégoire et al., 2003] CT-based delineation of lymph node levels and related CTVs in the node-negative neck : DAHANCA, EORTC, GORTEC, NCIC, RTOG consensus guidelines. Radiotherapy Oncology, 2003. 3