Magnetization EXchange (MEX) MRI Reveals Myelin Content in ex-vivo Rat Spinal Cord of Genetic Dysmyelination Mutants

Motivation: Developing an MT based sequence to quantify myelin in normal and abnormal brain tissue. Goal(s): (1) Demonstrate the sensitivity of the MEX sequence to minor and severe changes in myelin fraction. (2) Study the maturation process of a lesser-known Taiep model, that bears much resemblance to human disorders. Approach: Acquiring data by MRI and EM at 4 time-points, from 2 different genetic dysmyelination models, and controls. Results: The results reveal significant myelin decreased (36%) in impacted animals and lack of myelination with age. Values also establish the normal maturation and aging process of controls. Finally, the results highly correlate with EM values (R=0.88,p<0.0001). Impact: The results validate the MEX sequence capabilities to quantify myelin content, with the prospective of clinical use. The main challenge is reducing scan time. Additionally, the use of the Taiep model shows great promise for further studying genetic dysmyelination disorders.