MRI simulation: effect of gradient distortions on three-dimensional prostate cancer plans

Definition of the CTV Prostate in CT and MRI by Using CT–MRI Image Fusion in IMRT Planning for Prostate Cancer

“…However, this hypothesis was disproved: Mah et al [19] showed that no distortion occurred at the central part of the MRI scan, where the prostate was located. In addition, a recently published study by Jeong et al [15] reported a significant correlation between the prostate volume measured by using MRI and the actual prostate volume measured after radical prostatectomy.…”

Target localization for post‐prostatectomy patients using CT and ultrasound image guidance

“…All patients were treated in the supine position using an alpha cradle cast as previously described (19) . Target volumes and critical normal structures were contoured using the combined fused images from the CT and MR simulations as previously described (20) . CT and MR simulations were obtained using axial images obtained every 3 mm through the pelvis.…”

MR Imaging Based Treatment Planning for Radiotherapy of Prostate Cancer

“…Our previous study (Mah et al 2002a) estimated that the effect of image distortion was clinically insignificant for the prostate targets and nearby critical structures; they were all within 15 cm of the isocentre and the distortion error was found to be less than 2 mm on our low-field MR unit. The effect of residual image distribution on dose calculation (e.g., the effect on DVH calculation) was considered to be negligible after the GDC.…”

“…For system-related distortions, different image distortion correction methods have been developed (Finnigan et al 1997, Fransson et al 1998, Schad et al 1987, 1992, Schubert et al 1999. Mah et al (2002a) showed that with a gradient distortion correction (GDC) the distortions of the external contour from MRI were insignificant for 3DCRT of prostate cancer, based on the tissue-maximum ratio (TMR) analysis using a 0.23 T open system and a 1.5 T closed system.…”