Magnetic Resonance Elastography of Intervertebral Discs: Spin-Echo Echo-Planar Imaging Sequence Validation

Megan Co; Huiming Dong; Daniel J Boulter; Xuan V Nguyen; Safdar N Khan; Brian Raterman; Brett Klamer; Arunark Kolipaka; Benjamin A Walter

doi:10.1002/jmri.28151

Magnetic Resonance Elastography of Intervertebral Discs: Spin-Echo Echo-Planar Imaging Sequence Validation

J Magn Reson Imaging. 2022 Dec;56(6):1722-1732. doi: 10.1002/jmri.28151. Epub 2022 Mar 15.

Authors

Megan Co¹, Huiming Dong², Daniel J Boulter², Xuan V Nguyen², Safdar N Khan³, Brian Raterman², Brett Klamer⁴, Arunark Kolipaka^{1

2}, Benjamin A Walter^{1

2

5}

Affiliations

¹ Department of Biomedical Engineering, The Ohio State University, Columbus, Ohio, USA.
² Department of Radiology, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA.
³ Department of Orthopedics, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA.
⁴ Center for Biostatistics, The Ohio State University, Columbus, Ohio, USA.
⁵ Spine Research Institute, The Ohio State University, Columbus, Ohio, USA.

Abstract

Background: Magnetic resonance elastography (MRE) is an imaging technique that can noninvasively assess the shear properties of the intervertebral disc (IVD). Unlike the standard gradient recalled echo (GRE) MRE technique, a spin-echo echo-planar imaging (SE-EPI) sequence has the potential to improve imaging efficiency and patient compliance.

Purpose: To validate the use of an SE-EPI sequence for MRE of the IVD compared against the standard GRE sequence.

Study type: Cross-over.

Subjects: Twenty-eight healthy volunteers (15 males and 13 females, age range: 19-55).

Field strength/sequence: 3 T; GRE, SE-EPI with breath holds (SE-EPI-BH) and SE-EPI with free breathing (SE-EPI-FB) MRE sequences.

Assessment: MRE-derived shear stiffnesses were calculated via principal frequency analysis. SE-EPI derived shear stiffness and octahedral shear strain signal-to-noise ratios (OSS-SNR) were compared against those derived using the GRE sequence. The reproducibility and repeatability of SE-EPI stiffness measurements were determined. Shear stiffness was evaluated in the nucleus pulposus (NP) and annulus fibrosus (AF) regions of the disc. Scan times between sequences were compared.

Statistical tests: Linear mixed models, Bland-Altman plots, and Lin's concordance correlation coefficients (CCCs) were used with P < 0.05 considered statistically significant.

Results: Good correlation was observed between shear stiffnesses derived from the SE-EPI sequences with those derived from the GRE sequence with CCC values greater than 0.73 and 0.78 for the NP and AF regions, respectively. OSS-SNR was not significantly different between GRE and SE-EPI sequences (P > 0.05). SE-EPI sequences generated highly reproducible and repeatable stiffness measurements with CCC values greater than 0.97 in the NP and AF regions and reduced scan time by at least 51% compared to GRE. SE-EPI-BH and SE-EPI-FB stiffness measurements were similar with CCC values greater than 0.98 for both regions.

Data conclusion: SE-EPI-based MRE-derived stiffnesses were highly reproducible and repeatable and correlated with current standard GRE MRE-derived stiffness estimates while reducing scan times.

Level of evidence: 1 TECHNICAL EFFICACY STAGE: 1.

Keywords: intervertebral disc MRE; intervertebral disc stiffness; magnetic resonance elastography; spin-echo echo-planar imaging.

Publication types

Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't

MeSH terms

Adult
Echo-Planar Imaging / methods
Elasticity Imaging Techniques* / methods
Female
Humans
Intervertebral Disc* / diagnostic imaging
Magnetic Resonance Imaging / methods
Male
Middle Aged
Reproducibility of Results
Signal-To-Noise Ratio
Young Adult

Abstract

Publication types

MeSH terms

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