Detecting macromolecular differences of the CSF in low disability multiple sclerosis using quantitative MT MRI at 3T.

Background: Imaging investigation of cerebrospinal fluid (CSF) in multiple sclerosis (MS) is understudied. Development of noninvasive methods to detect pathological CSF changes would have a profound effect on MS diagnosis and would offer insight into MS pathophysiology and mechanisms of neurological impairment.

Objective: We propose magnetization transfer (MT) MRI as a tool to detect macromolecular changes in spinal CSF.

Methods: MT and quantitative MT (qMT) data were acquired in the cervical region in 27 people with relapsing-remitting multiple sclerosis (pwRRMS) and 38 age and sex-matched healthy controls (HCs). MT ratio (MTR), the B, B, and R corrected qMT-derived pool size ratio (PSR) were quantified in the spinal cord and CSF of each group.

Results: Both CSF MTR and CSF qMT-derived PSR were significantly increased in pwRRMS compared to HC ( = 0.027 and  = 0.020, respectively). CSF PSR of pwRRMS was correlated to Expanded Disability Status Scale Scores ( = 0.045, R = 0.352).

Conclusion: Our findings demonstrate increased CSF macromolecular content in pwRRMS and link CSF macromolecular content with clinical impairment. This highlights the potential role of CSF in processing products of demyelination.