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Updated: May 3, 2026
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Multimodal Volumetric Retinal Imaging by Oblique Scanning Laser Ophthalmoscopy oSLO and Optical Coherence Tomography OCT
Published on: August 4, 2018
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Gradient rotating outer volume excitation (GROOVE): A novel method for single-shot two-dimensional outer volume
Nathaniel J Powell1,2, Albert Jang1,3, Jang-Yeon Park4
1Center for Magnetic Resonance Research and Department of Radiology, University of Minnesota, Minneapolis, Minnesota, USA.
Magnetic Resonance in Medicine
|January 31, 2014
Summary
Gradient Rotating Outer Volume Excitation (GROOVE) is a novel MRI technique for outer volume suppression. It offers faster, lower SAR suppression with tailored spatial control, suitable for applications like scalp suppression.
Area of Science:
- Magnetic Resonance Imaging (MRI)
- Pulse Sequence Design
Background:
- Outer volume suppression (OVS) is crucial for limiting the field of view in MRI.
- Conventional OVS techniques can be time-consuming and have limitations in spatial tailoring.
Purpose of the Study:
- To introduce Gradient Rotating Outer Volume Excitation (GROOVE), a new OVS technique.
- To demonstrate GROOVE's ability to create tailored, circular, or elliptical suppression bands.
Main Methods:
- Theoretical and k-space analysis of the GROOVE technique.
- Simulations, phantom studies, and human experiments at 4T using a TEM coil.
Main Results:
- GROOVE achieved comparable suppression in phantoms and human brains.
- Simulations showed GROOVE has lower specific absorption rate (SAR) and reduced scan time compared to traditional OVS.
- Traditional methods offered sharper transitions and less residual signal.
Conclusions:
- GROOVE enables temporally excited spatial excitation for flexible, shaped OVS.
- This method offers faster, more adaptable OVS with lower SAR than conventional techniques.
- GROOVE is a promising alternative for specific applications like scalp suppression.
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