Quantification of Myelin in the Cervical Spinal Cord Using Inhomogeneous Magnetization Transfer Imaging

Novena Rangwala¹, Gopal Varma¹, David Hackney¹, David C. Alsop¹

Previous studies proposed a new magnetization transfer (MT)-based contrast mechanism referred to as inhomogeneous magnetization transfer (ihMT) and showed its sensitivity and specificity to myelin. This study extends the ihMT quantification to the brainstem and cervical spinal cord. Sagittal EPI images were acquired after MT saturation to measure myelin content along the length of the spinal cord. Results show ihMT ratios of ~5% in the brain stem, increasing to ~6.5% in the cervical spinal cord at C3, and were consistent across healthy volunteers. Additionally, the images reveal saturation of all tissues except white matter, emphasizing the specificity of the measure.