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Quantitative Magnetic Resonance Imaging of Skeletal Muscle Disease
Published on: December 18, 2016
[In-phase and out-of-phase single-shot magnetization-prepared gradient recalled echo: description and optimization of
M Ramalho1, V Herédia2, R O P de Campos3
1Department of Radiology, University of North Carolina at Chapel Hill, Carolina del Norte, EE. UU; Department of Radiology, Hospital Garcia de Orta, Almada, Portugal.
Radiologia
|June 20, 2012
Summary
Magnetization-Prepared Gradient Recalled Echo (MP-GRE) with in-phase and out-of-phase (IP/OP) techniques offers feasible, motion-resistant imaging. Optimized MP-GRE sequences provide adequate diagnostic quality, even for non-cooperative patients.
Area of Science:
- Radiology
- Medical Imaging
- Magnetic Resonance Imaging (MRI)
Background:
- Gradient Recalled Echo (GRE) sequences are widely used in MRI.
- Magnetization Preparation (MP) can enhance contrast and suppress artifacts.
- In-phase and out-of-phase (IP/OP) imaging is crucial for characterizing tissue composition, particularly fat.
Purpose of the Study:
- To implement and evaluate in-phase and out-of-phase (IP/OP) techniques with Magnetization-Prepared Gradient Recalled Echo (MP-GRE).
- To assess the feasibility and diagnostic image quality of pre- and post-optimized MP-GRE sequences.
- To include patients unable to cooperate with breath-hold requirements.
Main Methods:
- Retrospective study of 137 patients (46 noncooperative) divided into pre- and post-optimized MP-GRE groups.
- Utilized a single-shot 2D MP-GRE sequence, a motion-insensitive technique.
- Qualitative assessment by two radiologists for artifacts, image quality, and lesion conspicuity.
Main Results:
- Post-optimized MP-GRE IP/OP sequences demonstrated significantly reduced phase cancellation artifact compared to standard OP sequences.
- Bounce-point artifacts were more pronounced in pre-optimized IP sequences.
- Optimized IP/OP MP-GRE sequences showed superior overall image quality and were effective in identifying hepatic steatosis and adrenal adenomas.
Conclusions:
- Single-shot IP/OP MP-GRE is a feasible technique for motion-resistant imaging.
- The optimized sequences provide adequate diagnostic image quality, even in non-cooperative patients.
- This technique effectively provides IP and OP information for patients unable to suspend respiration.
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