Current use and possible future applications of the magnetization transfer technique in neuroradiology

Magnetization transfer (MT) imaging is a special MR technique used for selective suppression of the MR signal of protons bound on macromolecules. The most important applications in neuroradiology are (1) detection of subtle changes in otherwise normal-appearing cerebral white matter, for instance in multiple sclerosis (MS), Wallerian degeneration, and hydrocephalus, (2) differentiation of white matter lesions with high signal on T2-weighted MR-images, like MS plaques, brain infarctions, and brain edema, (3) follow-up of cerebral white matter diseases using volumetric MT techniques, and (4) improvement in delineating of contrast enhancing brain lesions, such as cerebral metastases. We describe the physical rationale of the MT technique and present the most important current and possible future applications of MT imaging to answer clinical and scientific questions in neuroradiology. (orig.)