Fig. 1From: Comparison of carina-based versus bony anatomy-based registration for setup verification in esophageal cancer radiotherapyIllustration of the systematic error (SE, the length of the arrow) and the SD of random errors (sdRE, the length of semi-major/minor axis of the ellipse) of each marker position relative to the carina, projected onto the coronal (left) and sagittal (right) views of the esophagus. Note: the amplitudes of the errors are not scaled to the esophagusBack to article page