Fig. 3
From: Interobserver variability in organ at risk delineation in head and neck cancer

CT images showing different OAR contours Reference contours according to the ICG (lilac) vs delineations from the different RO. a brainstem (sagittal plane): difference in cranial and caudal borders; b oral cavity, spinal cord and PG (axial plane): Inclusion of buccal mucosa (green contour) and teeth (orange and pink contours) by some RO. Variation in spinal cord and PG contours; c spinal cord (sagittal plane): difference in cranial and caudal borders. ICG international consensus guidelines, PG parotid glands, RO radiation oncologist