Patricia M Johnson1, Junmin Liu2, Trevor Wade2, Mohammad Ali Tavallaei3, Maria Drangova4. 1. Imaging Research Laboratories, Robarts Research Institute, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, Ontario, Canada; Department of Medical Biophysics, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, Ontario, Canada. 2. Imaging Research Laboratories, Robarts Research Institute, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, Ontario, Canada. 3. Imaging Research Laboratories, Robarts Research Institute, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, Ontario, Canada; Graduate Program in Biomedical Engineering, The University of Western Ontario, London, Ontario, Canada. 4. Imaging Research Laboratories, Robarts Research Institute, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, Ontario, Canada; Department of Medical Biophysics, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, Ontario, Canada; Graduate Program in Biomedical Engineering, The University of Western Ontario, London, Ontario, Canada. Electronic address: mdrangova@robarts.ca.
Abstract
PURPOSE: To develop and evaluate a rapid spherical navigator echo (SNAV) motion correction technique, then apply it for retrospective correction of brain images. METHODS: The pre-rotated, template matching SNAV method (preRot-SNAV) was developed in combination with a novel hybrid baseline strategy, which includes acquired and interpolated templates. Specifically, the SNAV templates are only rotated around X- and Y-axis; for each rotated SNAV, simulated baseline templates that mimic object rotation about the Z-axis were interpolated. The new method was first evaluated with phantom experiments. Then, a customized SNAV-interleaved gradient echo sequence was used to image three volunteers performing directed head motion. The SNAV motion measurements were used to retrospectively correct the brain images. Experiments were performed using a 3.0T whole-body MRI scanner and both single and 8-channel head coils. RESULTS: Phantom rotations and translations measured using the hybrid baselines agreed to within 0.9° and 1mm compared to those measured with the original preRot-SNAV method. Retrospective motion correction of in vivo images using the hybrid preRot-SNAV effectively corrected for head rotation up to 4° and 4mm. CONCLUSIONS: The presented hybrid approach enables the acquisition of pre-rotated baseline templates in as little as 2.5s, and results in accurate measurement of rotations and translations. Retrospective 3D motion correction successfully reduced motion artifacts in vivo.
PURPOSE: To develop and evaluate a rapid spherical navigator echo (SNAV) motion correction technique, then apply it for retrospective correction of brain images. METHODS: The pre-rotated, template matching SNAV method (preRot-SNAV) was developed in combination with a novel hybrid baseline strategy, which includes acquired and interpolated templates. Specifically, the SNAV templates are only rotated around X- and Y-axis; for each rotated SNAV, simulated baseline templates that mimic object rotation about the Z-axis were interpolated. The new method was first evaluated with phantom experiments. Then, a customized SNAV-interleaved gradient echo sequence was used to image three volunteers performing directed head motion. The SNAV motion measurements were used to retrospectively correct the brain images. Experiments were performed using a 3.0T whole-body MRI scanner and both single and 8-channel head coils. RESULTS: Phantom rotations and translations measured using the hybrid baselines agreed to within 0.9° and 1mm compared to those measured with the original preRot-SNAV method. Retrospective motion correction of in vivo images using the hybrid preRot-SNAV effectively corrected for head rotation up to 4° and 4mm. CONCLUSIONS: The presented hybrid approach enables the acquisition of pre-rotated baseline templates in as little as 2.5s, and results in accurate measurement of rotations and translations. Retrospective 3D motion correction successfully reduced motion artifacts in vivo.
Authors: Zhaolin Chen; Sharna D Jamadar; Shenpeng Li; Francesco Sforazzini; Jakub Baran; Nicholas Ferris; Nadim Jon Shah; Gary F Egan Journal: Hum Brain Mapp Date: 2018-08-04 Impact factor: 5.038
Authors: M Krämer; A G Motaal; K-H Herrmann; B Löffler; J R Reichenbach; G J Strijkers; V Hoerr Journal: J Cardiovasc Magn Reson Date: 2017-03-31 Impact factor: 5.364
Authors: Lucilio Cordero-Grande; Giulio Ferrazzi; Rui Pedro A G Teixeira; Jonathan O'Muircheartaigh; Anthony N Price; Joseph V Hajnal Journal: Magn Reson Med Date: 2020-01-03 Impact factor: 4.668