BRAIN AND CORD MAGNETIZATION TRANSFER IMAGING HISTOGRAMS IN MULTIPLE SCLEROSIS PATIENTS

Brain and cervical cord MRl measures and MTR histogram parameters in the whole MS group and in each of the three clinical phenotypes are reported in the Table. Brain T2 and Tl TLV, brain MTR histogram peak location, number of cord lesions and cord MTR histogram peak location were significantly heterogeneous among the three MS phenotypes (ANOVA test, p values ranging from 0.001 to 0.04). At post-hoc analysis (corrected with Bonferroni adjustment for multiple comparisons), brain T2 TLV was significantly higher in SPMS than in RRMS and PPMS patients, brain MTR histogram peak location was significantly lower in SPMS than in RRMS and PPMS patients, the number of cord lesions was significantly higher in SPMS than in RRMS and PPMS patients, cord MTR histogram peak location was significantly lower in SPMS than in RRMS patients. Brain T2 TLV was significantly correlated with average cord MTR (SRCC: -0.2, p=O.O5). The univariate correlations between MTR histogram-derived metrics obtained from the brain and the cervical cord were all not significant with the exception of that between average brain MTR and cord MTR histogram peak location (SRCC 0.3, p=O.OOS). On a multivariable analysis, both brain T2 TLV and cord MTR histogram peak location fitted a model significantly separating (p = 0.01 and 0.02, respectively) MS patients with RR and SP courses. Odd ratio values were 1.05 for T2 TLV and 0.81 for cord MTR histogram peak location. The same variables fitted a model significantly separating (p = 0.006 and 0.0008, respectively) MS patients with and without locomotor disability. Odd ratio values were 1.06 for T2 lesion load and 0.77 for cord MTR histogram peak location.