Comparison of T1r and T2 * Relaxation Mapping in Patients with Different Grades of Disc Degeneration at 3T MR

Source of support: Departmental sources Background: T1r and T2 * relaxation times are capable of providing information about early biochemical changes in inter-vertebral disk degeneration (IVDD). The purpose of this study was to assess and compare T1r and T2 * map-ping in IVDD with reference to Pfirrmann grade. Material/Methods: Lumbar sagittal T2-weighted, T1r and T2 * relaxation MRI were performed at 3.0T in 42 subjects covering discs L1–L2 to L5–S1. All the discs were morphologically assessed according to the Pfirrmann grade. Regions of in-terest (ROIs) were drawn over the T1r and T2*mappings, including nucleus pulposus (NP) and annulus fibro-sus (AF). Wilcoxon signed rank test, Kruskal-Wallis test, and Spearman rank correlation were performed. Results: The difference in T1r and T2 * values between NP and AF were highly significant (P<0.001). The trends of de-creasing T1r and T2 * values of both NP and AF with increasing Pfirrmann grades was significant (P<0.01), par-ticularly between Pfirrmann grade II and III (P<0.001), whereas T2 * mapping was additionally able to detect changes in the AF between Pfirrmann grade I and II (P<0.05). Pfirrmann grades were inversely significantly cor