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Reducing chemical shift artifacts in MRI in time-varying gradients
1Hitachi Ltd., Kawasaki.
IEEE Transactions on Medical Imaging
|January 1, 1989
Summary
This study presents an algorithm to reduce chemical shift artifacts in magnetic resonance imaging (MRI) using time-varying gradients. The method effectively obtains clear chemical shift images without extending scan times.
Area of Science:
- Medical Imaging
- Image Processing
- Biophysics
Background:
- Chemical shift artifacts in MRI degrade image quality, particularly with time-varying gradients like in spiral-type scanning.
- These artifacts are significant as they possess the same power as the in-focus point spread function (PSF).
Purpose of the Study:
- To develop an image processing algorithm for reducing chemical shift artifacts in MRI.
- To obtain chemical shift images without increasing imaging time.
Main Methods:
- An iterative estimation algorithm is proposed to separate chemical shift images.
- The algorithm incorporates an a priori constraint for real and nonnegative image values.
Main Results:
- Computer simulations demonstrate significant reduction in average artifact amplitude after several iterations.
- The algorithm shows robustness and effectiveness even in the presence of observation noise.
Conclusions:
- The presented algorithm effectively reduces chemical shift artifacts in MRI.
- This method allows for artifact reduction and clear chemical shift image acquisition without prolonging MRI scan duration.
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