MR Elastography-derived Stiffness: A 31omarker for Intervertebral Disc Degeneration

作者:Walter Benjamin A; Mageswaran Prasath; Mo Xiaokui; Boulter Daniel J; Mashaly Hazem; Nguyen Xuan V; Prevedello Luciano M; Thoman William; Raterman Brian D; Kalra Prateek; Mendel Ehud; Marras William S; Kolipaka Arunark*
来源:Radiology, 2017, 285(1): 167-175.
DOI:10.1148/radiol.2017162287

摘要

Purpose: To determine the repeatability of magnetic resonance (MR) elastography-derived shear stiffness measurements of the intervertebral disc (IVD) taken throughout the day and their relationship with IVD degeneration and subject age. Materials and Methods: In a cross-sectional study, in vivo lumbar MR elastography was performed once in the morning and once in the afternoon in 47 subjects without current low back pain (IVDs = 230; age range, 20-71 years) after obtaining written consent under approval of the institutional review board. The Pfirrmann degeneration grade and MR elastography-derived shear stiffness of the nucleus pulposus and annulus fibrosus regions of all lumbar IVDs were assessed by means of principal frequency analysis. One-way analysis of variance, paired t tests, concordance and Bland-Altman tests, and Pearson correlations were used to evaluate degeneration, diurnal changes, repeatability, and age effects, respectively. Results: There were no significant differences between morning and afternoon shear stiffness across all levels and there was very good technical repeatability between the morning and afternoon imaging results for both nucleus pulposus (R = 0.92) and annulus fibrosus (R = 0.83) regions. There was a significant increase in both nucleus pulposus and annulus fibrosus MR elastography-derived shear stiffness with increasing Pfirrmann degeneration grade (nucleus pulposus grade 1, 12.5 kPa +/- 1.3; grade 5, 16.5 kPa +/- 2.1; annulus fibrosus grade 1, 90.4 kPa +/- 9.3; grade 5, 120.1 kPa +/- 15.4), and there were weak correlations between shear stiffness and age across all levels (R = 0.32). Conclusion: Our results demonstrate that MR elastography-derived shear stiffness measurements are highly repeatable, weakly correlate with age, and increase with advancing IVD degeneration. These results suggest that MR elastography-derived shear stiffness may provide an objective biomarker of the IVD degeneration process.

  • 出版日期2017-10