New non-invasive technique to visualize three-dimensional anatomical structures of myelinated white matter tracts of human brain in vivo.

We have developed a new non-invasive technique to visualize three-dimensional anatomical structures of myelinated white matter tracts of the human brain in vivo. The basic principle of our idea is the combination of the magnetic resonance (MR) imaging technique, which represents the myelinated white matter tracts as hyperintense signal areas, and the post-image processing technique, which extracts only hyperintense areas on the image. The intravoxel incoherent motion imaging sequence was used for the former step. The maximum intensity projection method, on the other hand, was utilized for the latter step. To examine the clinical usefulness of the idea, normal volunteers and selected patients with paralysis were investigated on a 1.5 Tesla MR system. The structure of white matter tracts of normal volunteers was found to be in good agreement with known anatomy. The structure of the nerve fiber system of patients with paralysis, on the other hand, reflected some abnormalities of the nerve fibers and correlated with clinical symptoms. Some results of clinical examinations with our proposed technique showed great promise for the study of neuroanatomy and neuroradiology.