Skip to main content
Fig. 1 | Radiation Oncology

Fig. 1

From: A review of substitute CT generation for MRI-only radiation therapy

Fig. 1

Variability of multiple registrations between MRI and the corresponding CT for prostate (top) and nasopharynx (bottom). a: One marker (of three) indicated by a white circle on the axial MRI. b: Two markers shown by the white dots on the sagittal CT. The multiple thin white lines are the MRI delineated clinical target volume (CTV) transferred to the CT based on the marker registration following department protocol from 7 different observers. The protocol is based on a rigid automatic (mutual information) registration for a limited FOV around the prostate followed by a manual adjustment to match the markers in the three planes. The outermost white line was the planned target volume (PTV) applied. The data are taken from reference [59]. c: The gross target volume (inner) and CTV (outer) as delineated on the axial MRI. d: The multiple thin white lines are the MRI based CTV transferred to the CT by 6 different observers (sagital CT slice shown). The registration is based on a rigid automatic (mutual information) registration followed by a manual fine adjustment. The outermost white line was again the applied PTV. The data are taken from reference [60]

Back to article page