PURPOSE: MR-based attenuation correction (AC) will become an integral part of combined PET/MR systems. Here, we propose a toolbox to validate MR-AC of clinical PET/MRI data sets. METHODS: Torso scans of ten patients were acquired on a combined PET/CT and on a 1.5-T MRI system. MR-based attenuation data were derived from the CT following MR-CT image co-registration and subsequent histogram matching. PET images were reconstructed after CT- (PET(CT)) and MR-based AC (PET(MRI)). Lesion-to-background (L/B) ratios were estimated on PET(CT) and PET(MRI). RESULTS: MR-CT histogram matching leads to a mean voxel intensity difference in the CT- and MR-based attenuation images of 12% (max). Mean differences between PET(MRI) and PET(CT) were 19% (max). L/B ratios were similar except for the lung where local misregistration and intensity transformation leads to a biased PET(MRI). CONCLUSION: Our toolbox can be used to study pitfalls in MR-AC. We found that co-registration accuracy and pixel value transformation determine the accuracy of PET(MRI).
PURPOSE: MR-based attenuation correction (AC) will become an integral part of combined PET/MR systems. Here, we propose a toolbox to validate MR-AC of clinical PET/MRI data sets. METHODS: Torso scans of ten patients were acquired on a combined PET/CT and on a 1.5-T MRI system. MR-based attenuation data were derived from the CT following MR-CT image co-registration and subsequent histogram matching. PET images were reconstructed after CT- (PET(CT)) and MR-based AC (PET(MRI)). Lesion-to-background (L/B) ratios were estimated on PET(CT) and PET(MRI). RESULTS: MR-CT histogram matching leads to a mean voxel intensity difference in the CT- and MR-based attenuation images of 12% (max). Mean differences between PET(MRI) and PET(CT) were 19% (max). L/B ratios were similar except for the lung where local misregistration and intensity transformation leads to a biased PET(MRI). CONCLUSION: Our toolbox can be used to study pitfalls in MR-AC. We found that co-registration accuracy and pixel value transformation determine the accuracy of PET(MRI).
Authors: Gerald Antoch; Florian M Vogt; Lutz S Freudenberg; Fridun Nazaradeh; Susanne C Goehde; Jörg Barkhausen; Gerlinde Dahmen; Andreas Bockisch; Jörg F Debatin; Stefan G Ruehm Journal: JAMA Date: 2003-12-24 Impact factor: 56.272
Authors: V Schulz; I Torres-Espallardo; S Renisch; Z Hu; N Ojha; P Börnert; M Perkuhn; T Niendorf; W M Schäfer; H Brockmann; T Krohn; A Buhl; R W Günther; F M Mottaghy; G A Krombach Journal: Eur J Nucl Med Mol Imaging Date: 2010-10-05 Impact factor: 9.236
Authors: David Izquierdo-Garcia; Stephen J Sawiak; Karin Knesaurek; Jagat Narula; Valentin Fuster; Joseph Machac; Zahi A Fayad Journal: Eur J Nucl Med Mol Imaging Date: 2014-03-21 Impact factor: 9.236