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Magnetic Resonance Imaging of Multiple Sclerosis at 7.0 Tesla
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Fast parallel spiral chemical shift imaging at 3T using iterative SENSE reconstruction
Dirk Mayer1, Dong-Hyun Kim, Daniel M Spielman
1Stanford University, Richard M. Lucas Center for Magnetic Resonance Spectroscopy and Imaging, Department of Radiology, Stanford, California 94305-5488, USA. dirk.mayer@stanford.edu
Magnetic Resonance in Medicine
|April 3, 2008
Summary
This study introduces parallel spiral chemical shift imaging (CSI) to accelerate brain metabolite mapping. The new method significantly reduces scan time while maintaining comparable image quality to conventional techniques.
Area of Science:
- Magnetic Resonance Imaging
- Neuroimaging
- Metabolomics
Background:
- Spiral chemical shift imaging (CSI) offers rapid acquisition by encoding spectral and spatial information simultaneously.
- Achieving desired spectral bandwidth in spiral CSI often requires multiple excitations due to gradient limitations, increasing scan time.
- Existing methods necessitate fully sampled data for reliable metabolite mapping.
Purpose of the Study:
- To reduce the minimum total measurement time for spiral CSI.
- To accelerate 2D-CSI experiments using an iterative sensitivity encoding (SENSE) reconstruction algorithm.
- To evaluate the performance of parallel spiral CSI in phantom and in vivo experiments.
Main Methods:
- Reduced the number of spatial interleaves in spiral CSI acquisition.
- Employed an iterative SENSE reconstruction algorithm leveraging coil sensitivity profiles for spatial encoding.
- Validated the method using phantom and in vivo brain imaging experiments.
Main Results:
- Parallel spiral CSI successfully generated brain metabolite maps comparable to conventional methods.
- Achieved a reduction in minimum total measurement time for spiral CSI.
- Observed only a minor decrease in time-normalized signal-to-noise ratio and a slight noise increase at higher acceleration factors.
Conclusions:
- Parallel spiral CSI is a viable accelerated technique for brain metabolite mapping.
- The iterative SENSE reconstruction effectively compensates for undersampling in spiral CSI.
- This acceleration holds promise for more efficient neuroimaging studies.
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