In Vivo Quantitative Whole-Brain T1 rho MRI of Multiple Sclerosis

Background: To apply quantitative whole-brain T-1-rho (T-1 rho) and T-2 imaging to the detection and quantification of brain changes resulting from multiple sclerosis (MS). Methods: Twenty-three MS patients with clinically isolated syndrome (10) and relapsing remitting MS (13) phenotypes, compared with 24 age-matched healthy controls were imaged at 3 Tesla. An axial T-1 rho-weighted three-dimensional turbo spin echo sequence with a variable flip angle and fluid suppression was used. Spin-lock times of 0, 20, 40, 60, 80, and 100 ms were used. Corresponding T-2 maps were also acquired. Results: Whole brain white matter (WM) T-1 rho maps were elevated compared with controls (P = 0.002). WM lesion T-1 rho and T-2 values were highly correlated (r = 0.83), but T-1 rho demonstrated 25% better contrast to noise ratio (P < 0.001). WM lesion T-1 rho correlated with disease duration. Gray matter T-1 rho was negatively correlated with the Expanded Disability Status Scale, r = -0.45, P = 0.03. Normal appearing gray matter and cortical gray matter lesions were negatively correlated on T-1 rho, but not on T-2 (r(T1 rho) = -0.63, p(T1 rho) = 0.03; r(T2) = -0.17, p(T2) = 0.6). Conclusion: T-1 rho MRI demonstrates enhanced lesion contrast compared with T-2, and in some cases may provide complementary information. T-1 rho may provide a useful measure of demyelinating processes in MS.