Comparison of T1ρ and T2* Relaxation Mapping in Patients with Different Grades of Disc Degeneration at 3T MR
Xinjuan Zhang, Li Yang, Fei Gao, Zhenguo Yuan, Xiangtao Lin, Bin Yao, Weibo Chen, Queenie Chan, Guangbin Wang
(Department of Radiology, Shandong Medical Imaging Research Institute, Shandong University, Jinan, Shandong, China (mainland))
Med Sci Monit 2015; 21:1934-1941
T1ρ and T2* relaxation times are capable of providing information about early biochemical changes in intervertebral disk degeneration (IVDD). The purpose of this study was to assess and compare T1ρ and T2* mapping in IVDD with reference to Pfirrmann grade.
MATERIAL AND METHODS: Lumbar sagittal T2-weighted, T1ρ 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 interest (ROIs) were drawn over the T1ρ and T2*mappings, including nucleus pulposus (NP) and annulus fibrosus (AF). Wilcoxon signed rank test, Kruskal-Wallis test, and Spearman rank correlation were performed.
RESULTS: The difference in T1ρ and T2* values between NP and AF were highly significant (P<0.001). The trends of decreasing T1ρ and T2* values of both NP and AF with increasing Pfirrmann grades was significant (P<0.01), particularly 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 correlated with both T1ρ and T2* values in the NP (r=–0.69, P<0.001; r=–0.56, P<0.001) and AF (r=–0.45, P<0.001; r=–0.26, P<0.001).
CONCLUSIONS: ... read more
Keywords: Early Diagnosis, intervertebral disc degeneration, Lumbar Vertebrae, Magnetic Resonance Imaging