OBJECTIVE: Positron emission tomography (PET) provides an accurate measurement of radiotracer concentration in vivo, but performance can be limited by subject motion which degrades spatial resolution and quantitative accuracy. This effect may become a limiting factor for PET studies in the body as PET scanner technology improves. In this work, we propose a new approach to address this problem by employing motion information from images measured simultaneously using a magnetic resonance (MR) scanner. METHODS: The approach is demonstrated using an MR-compatible PET scanner and PET-MR acquisition with a purpose-designed phantom capable of non-rigid deformations. Measured, simultaneously acquired MR data were used to correct for motion in PET, and results were compared with those obtained using motion information from PET images alone. RESULTS: Motion artefacts were significantly reduced and the PET image quality and quantification was significantly improved by the use of MR motion fields, whilst the use of PET-only motion information was less successful. CONCLUSIONS: Combined PET-MR acquisitions potentially allow PET motion compensation in whole-body acquisitions without prolonging PET acquisition time or increasing radiation dose. This, to the best of our knowledge, is the first study to demonstrate that simultaneously acquired MR data can be used to estimate and correct for the effects of non-rigid motion in PET.
OBJECTIVE: Positron emission tomography (PET) provides an accurate measurement of radiotracer concentration in vivo, but performance can be limited by subject motion which degrades spatial resolution and quantitative accuracy. This effect may become a limiting factor for PET studies in the body as PET scanner technology improves. In this work, we propose a new approach to address this problem by employing motion information from images measured simultaneously using a magnetic resonance (MR) scanner. METHODS: The approach is demonstrated using an MR-compatible PET scanner and PET-MR acquisition with a purpose-designed phantom capable of non-rigid deformations. Measured, simultaneously acquired MR data were used to correct for motion in PET, and results were compared with those obtained using motion information from PET images alone. RESULTS: Motion artefacts were significantly reduced and the PET image quality and quantification was significantly improved by the use of MR motion fields, whilst the use of PET-only motion information was less successful. CONCLUSIONS: Combined PET-MR acquisitions potentially allow PET motion compensation in whole-body acquisitions without prolonging PET acquisition time or increasing radiation dose. This, to the best of our knowledge, is the first study to demonstrate that simultaneously acquired MR data can be used to estimate and correct for the effects of non-rigid motion in PET.
Authors: Se Young Chun; Timothy G Reese; Jinsong Ouyang; Bastien Guerin; Ciprian Catana; Xuping Zhu; Nathaniel M Alpert; Georges El Fakhri Journal: J Nucl Med Date: 2012-06-28 Impact factor: 10.057
Authors: Xiao Jin; Chung Chan; Tim Mulnix; Vladimir Panin; Michael E Casey; Chi Liu; Richard E Carson Journal: Phys Med Biol Date: 2013-07-29 Impact factor: 3.609
Authors: Thomas E Yankeelov; Todd E Peterson; Richard G Abramson; David Izquierdo-Garcia; David Garcia-Izquierdo; Lori R Arlinghaus; Xia Li; Nkiruka C Atuegwu; Ciprian Catana; H Charles Manning; Zahi A Fayad; John C Gore Journal: Magn Reson Imaging Date: 2012-07-15 Impact factor: 2.546