Nipah Viral Encephalitis or Japanese Encephalitis? MR Findings in a New Zoonotic Disease

Patient 1.

A, Multiple punctate white matter lesions (arrowheads) are visible on T2-weighted FSE MR image (4000/105).

B, The largest lesion is more prominent on corresponding diffusion-weighted image (10,000/105; b = 1000).

Patient 6.

A and B, Proton density–weighted (A) and T2-weighted FSE (3800/22,90) (B) MR images at different levels show innumerable small lesions scattered throughout the white matter bilaterally.

Patient 5.

A, T2-weighted MR image (4000/105) shows a lesion in the corpus callosum (arrowhead) and several smaller punctate hyperintensities (arrows).

B, Only the larger lesion in the corpus callosum is visible on corresponding diffusion-weighted image (10,000/105; b = 1000).

C, Axial contrast-enhanced T1-weighted image (540/14) shows several foci of enhancement (arrows).

D, Hyperintensities are seen in the pons and cerebellar peduncle (arrows) on T2-weighted image.

Patient 8.

A, Cortical hyperintensity (arrow) is poorly seen on this degraded T2-weighted MR image (5400/99).

B, The lesion (arrow) is much better visualized on FLAIR image (9000/110; TI=2500).

C, Coronal contrast-enhanced image (665/20) shows gyriform enhancement in the parietal cortex (arrow).