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Motion compensated projection reconstruction.

T Schäffter·V Rasche·I C Carlsen
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Abstract

Over recent years, MRI has shown the capability for real-time applications. Although the acquisition times of fast MRI methods have been reduced significantly, patient motion during a magnetic resonance imaging (MRI) examination still causes artifacts in the image. In this paper, the effects of motion in MRI using a radial acquisition scheme are examined. It is shown that motion can be estimated without the use of additional measurement, based on the acquired projections only. A new reconstruction technique is introduced that integrates a motion compensation algorithm into the MR-reconstruction process, resulting in a significant reduction of blurring artifacts in the reconstructed images. The proposed method is applied to different kinds of motion such as kinetic joint studies.

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AlgorithmsArtifactsFeasibility StudiesHumansImage Processing, Computer-AssistedKnee JointMagnetic Resonance ImagingModels, BiologicalMovementTime FactorsWrist JointJournal Article

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T Schäffter, V Rasche, I C Carlsen. 1999. Motion compensated projection reconstruction.. https://doi.org/10.1002/(sici)1522-2594(199905)41%3A5%3C954%3A%3Aaid-mrm15%3E3.0.co%3B2-j

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