Abstract

In this study, a new algorithm for canceling a MRI artifact due to the translational motion in image plane is described. Unlike the conventional iterative phase retrieval algorithm, in which there is no guarantee for the convergence, a direct method for estimating the motion is presented. In previous approaches, the motions in the x(read out) direction and the y(phase encoding) direction were estimated simultaneously. However, the feature of x and y directional motions are different from each other. By analyzing their features, each x and y directional motion is canceled by the different algorithms in two steps. First, it is noticed that the x directional motion corresponds to a shift of the x directional spectrum of the MRI signal, and the non-zero area of the spectrum just corresponds to the projected area of the density function on the x axis. So the motion is estimated by tracing the edges between non-zero area and zero area of the spectrum, and the x directional motion is canceled by shifting the spectrum in an reverse direction. Next, the y directional motion canceled by using a new constraint condition, with which the motion component and the true image component can be separated. This algorithm is shown to be effective by using a phantom image with simulated motion.

Meeting Name

19th IEEE Instrumentation and Measurement Technology Conference: IMTC (2002: May 21-23, Anchorage, AK)

Department(s)

Electrical and Computer Engineering

Keywords and Phrases

Fourier Spectrum; Fourier Transforms; MRI Motion Artifact Cancellation; Artifact Correction; Biomedical MRI; Constraint Condition; Direct Method; Directional Motion; Image Plane; Image Reconstruction; Iterative Phase Retrieval Algorithm; Medical Image Processing; Motion Compensation; Motion Estimation; Phantom Image; Postprocessing Algorithm; Reconstructed Image; Translational Motion; Fourier or Phase Spectrum; Motion Artifact; MRI; Reconstructed; Shifting

International Standard Book Number (ISBN)

780372182

International Standard Serial Number (ISSN)

1091-5281

Document Type

Article - Conference proceedings

Document Version

Final Version

File Type

text

Language(s)

English

Rights

© 2002 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 May 2002

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