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Objective: The potential of magnetization transfer imaging (MTI) and diffusion tensor imaging (DTI) for the detection and evolution of new multiple sclerosis (MS) lesions was analyzed., Methods: Nineteen patients with MS obtained conventional MRI, MTI, and DTI examinations bimonthly for 12 months and again after 24 months at 1.5 T MRI. MTI was acquired with balanced steady-state free precession (bSSFP) in 10 min (1.3 mm 3 isotropic resolution) yielding both magnetization transfer ratio (MTR) and quantitative magnetization transfer (qMT) parameters (pool size ratio (F), exchange rate (kf), and relaxation times (T1/T2)). DTI provided fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD)., Results: At the time of their appearance on MRI, the 21 newly detected MS lesions showed significantly reduced MTR/F/kf and prolonged T1/T2 parameters, as well as significantly reduced FA and increased AD/MD/RD. Significant differences were already observed for MTR 4 months and for qMT parameters 2 months prior to lesions' detection on MRI. DTI did not show any significant pre-lesional differences. Slightly reversed trends were observed for most lesions up to 8 months after their detection for qMT and less pronounced for MTR and three diffusion parameters, while appearing unchanged on MRI., Conclusions: MTI provides more information than DTI in MS lesions and detects tissue changes 2 to 4 months prior to their appearance on MRI. After lesions' detection, qMT parameter changes promise to be more sensitive than MTR for the lesions' evolutional assessment. Overall, bSSFP-based MTI adumbrates to be more sensitive than MRI and DTI for the early detection and follow-up assessment of MS lesions., Clinical Relevance Statement: When additionally acquired in routine MRI, fast bSSFP-based MTI can complement the MRI/DTI longitudinal lesion assessment by detecting MS lesions 2-4 months earlier than with MRI, which could implicate earlier clinical decisions and better follow-up/treatment assessment in MS patients., Key Points: • Magnetization transfer imaging provides more information than DTI in multiple sclerosis lesions and can detect tissue changes 2 to 4 months prior to their appearance on MRI. • After lesions' detection, quantitative magnetization transfer changes are more pronounced than magnetization transfer ratio changes and therefore promise to be more sensitive for the lesions' evolutional assessment. • Balanced steady-state free precession-based magnetization transfer imaging is more sensitive than MRI and DTI for the early detection and follow-up assessment of multiple sclerosis lesions., (© 2023. The Author(s).)

In multiple sclerosis (MS) more than 95% of the patients have positive oligoclonal bands (OCB) in the cerebrospinal fluid (CSF). Previous studies have reported differences between patients with and without OCB mainly with regard to clinical parameters such as age, gender, disease duration, and clinical severity. However, several MRI characteristics have also been hypothesized to be distinct, and a varying lesion load in OCB-negative and -positive patients is proposed. In this study, we aimed to evaluate whether Barkhof's diagnostic MRI criteria are unequally frequently fulfilled in OCB-negative and -positive MS patients. We screened our database for all OCB-negative MS patients who had (1) been treated with the diagnosis of a clinical definite relapsing-remitting MS in our institution as well as (2) undergone CSF analysis and MR brain imaging during hospital stay between January 2004 and December 2007. Eleven OCB-negative patients were identified who fulfilled these criteria. In a second step, we carefully matched each of them to two OCB-positive controls according to age, gender, EDSS, and disease duration. The separate analysis of the several parameters of Barkhof's criteria revealed a less frequent prevalence of infratentorial (3/11 vs. 18/22; P = 0.005) and a more frequent occurrence of juxtacortical lesions (10/11 vs. 10/22; P = 0.022) in OCB-negative as compared to OCB-positive patients. The overall fulfillment of the Barkhof criteria did not differ in OCB-negative and -positive patients (7/11 vs. 16/22; P = 0.696). Further analyses of MRI findings between OCB-negative and -positive MS patients might contribute to a better pathophysiological understanding of the genesis and evidence of OCB in the CSF of MS patients.