Sodium MRI of the Lumbar Intervertebral Discs of the Human Spine: An Ex Vivo Study

Lower back pain affects 75%-85% of people at some point in their lives. The detection of biochemical changes with sodium ( Na) MRI has potential to enable an earlier and more accurate diagnosis. To measure Na relaxation times and apparent tissue sodium concentration (aTSC) in ex-vivo intervertebral discs (IVDs), and to investigate the relationship between aTSC and histological Thompson grade. Ex-vivo. Thirty IVDs from the lumbar spines of 11 human body donors (4 female, 7 male, mean age 86 ± 8 years). 3 T; density-adapted 3D radial sequence (DA-3D-RAD). IVD Na longitudinal (T ), short and long transverse (T * and T *) relaxation times and the proportion of the short transverse relaxation (p ) were calculated for one IVD per spine sample (11 IVDs). Furthermore, aTSCs were calculated for all IVDs. The degradation of the IVDs was assessed via histological Thompson grading. A Kendall Tau correlation (τ) test was performed between the aTSCs and the Thompson grades. The significance level was set to P