Dataset Information

Revealing sub-voxel motions of brain tissue using phase-based amplified MRI (aMRI).

ABSTRACT: PURPOSE:Amplified magnetic resonance imaging (aMRI) was recently introduced as a new brain motion detection and visualization method. The original aMRI approach used a video-processing algorithm, Eulerian video magnification (EVM), to amplify cardio-ballistic motion in retrospectively cardiac-gated MRI data. Here, we strive to improve aMRI by incorporating a phase-based motion amplification algorithm. METHODS:Phase-based aMRI was developed and tested for correct implementation and ability to amplify sub-voxel motions using digital phantom simulations. The image quality of phase-based aMRI was compared with EVM-based aMRI in healthy volunteers at 3T, and its amplified motion characteristics were compared with phase-contrast MRI. Data were also acquired on a patient with Chiari I malformation, and qualitative displacement maps were produced using free form deformation (FFD) of the aMRI output. RESULTS:Phantom simulations showed that phase-based aMRI has a linear dependence of amplified displacement on true displacement. Amplification was independent of temporal frequency, varying phantom intensity, Rician noise, and partial volume effect. Phase-based aMRI supported larger amplification factors than EVM-based aMRI and was less sensitive to noise and artifacts. Abnormal biomechanics were seen on FFD maps of the Chiari I malformation patient. CONCLUSION:Phase-based aMRI might be used in the future for quantitative analysis of minute changes in brain motion and may reveal subtle physiological variations of the brain as a result of pathology using processing of the fundamental harmonic or by selectively varying temporal harmonics. Preliminary data shows the potential of phase-based aMRI to qualitatively assess abnormal biomechanics in Chiari I malformation.

SUBMITTER: Terem I

PROVIDER: S-EPMC6269230 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Revealing sub-voxel motions of brain tissue using phase-based amplified MRI (aMRI).

Terem Itamar I Ni Wendy W WW Goubran Maged M Rahimi Mahdi Salmani MS Zaharchuk Greg G Yeom Kristen W KW Moseley Michael E ME Kurt Mehmet M Holdsworth Samantha J SJ

Magnetic resonance in medicine 20180530 6

<h4>Purpose</h4>Amplified magnetic resonance imaging (aMRI) was recently introduced as a new brain motion detection and visualization method. The original aMRI approach used a video-processing algorithm, Eulerian video magnification (EVM), to amplify cardio-ballistic motion in retrospectively cardiac-gated MRI data. Here, we strive to improve aMRI by incorporating a phase-based motion amplification algorithm.<h4>Methods</h4>Phase-based aMRI was developed and tested for correct implementation and ...[more]

PMID: 29845645

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Dataset Information

Revealing sub-voxel motions of brain tissue using phase-based amplified MRI (aMRI).

Publications

Revealing sub-voxel motions of brain tissue using phase-based amplified MRI (aMRI).

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