Figure 3
From: Validation of Varian’s SmartAdapt® deformable image registration algorithm for clinical application
Comparison of DIR-generated (purple), RO re- contoured (green), and initially delineated planning CT structures (yellow). Panels (a/b) show an example where the low soft-tissue contrast induced an incorrect shift of DIR-generated structure of the spinal cord; (c) intra-observer variation in the delineation of the brain stem; (d) uncertainty at the cranial and caudal boundary of C4 delineation due to limited slice resolution; (e/f) difference between DIR-generated and the RO-modified CTV after tumour regression.