Figure 9.

Gold standard rCT DVH overlaid with dCT DVHs calculated using either directly outlined rCT structures ‘dCT (rCT)’ or deformed pCT structures ‘dCT (dCT)’ for a single patient. The dCT (rCT) matches the rCT DVH well, whereas the dCT (dCT) is noticeably different for all structures with the exception of the lungs. It should be noted that spinal canal  +  5 mm differences are largely attributable to outlining differences—the rCT structure extends further than the pCT (and hence the deformed) structure in both the superior and inferior directions. However, this is not an issue as only Dmax is considered for serial structures such as this.