Figure 17.

A 50-year-old normal control (left column) and Case 1, a 51-year-old with methamphetamine use disorder (right column). 2D dSIR narrow mD images are shown. The narrow mD dSIR images in the normal control show most white matter as very low signal intensity (dark) with a mid gray and lighter appearance in and around the corticospinal tracts, i.e., whiteout sign grade 1. The narrow mD dSIR images in the patient show widespread high signal changes in white matter with only small areas of normal dark white matter at the periphery of the white matter (white arrows). The features are consistent with a whiteout sign grade 4. Normal high signal boundaries are seen between white matter and gray matter on the dSIR images in the control and the patient, but are less obvious in the patient because of the high signal in his abnormal white matter.