FIG 3. Only mild hyperintensity was seen on diffusion-weighted MR images of a patient with myelitis.

A, Diffusion-weighted interleaved echo-planar image shows diffuse signal hyperintensity and swelling of the cervical spinal cord (open arrows). Note the signal cancellation due to ghosting artifacts (closed arrows) caused by bulk motion.

B, T2-weighted interleaved echo-planar image shows diffuse signal hyperintensity and swelling of the cervical spinal cord (open arrows), consistent with myelitis.

C, Region-of-interest measurements on corresponding apparent diffusion coefficient maps reveal moderately increased apparent diffusion coefficient values. Therefore, hyperintensity in diffusion-weighted MR imaging seems to be related to the so-called "T2-shine-through" effect that compensates for increased apparent diffusion coefficient.

D, Diffusion-weighted interleaved echo-planar image obtained at follow-up 7 months later. No pathologic signal alteration is seen.

E, T2-weighted interleaved echo-planar image obtained at follow-up 7 months later. The cord volume appears normal, and only faint intramedullary hyperintensities have remained.

F, Apparent diffusion coefficient map shows a small area with elevated apparent diffusion coefficient at the level between the medulla oblongata and C1 (arrowhead), which may represent residual damage.