Selective neuronal necrosis associated with status epilepticus: MR findings

Abstract

We present the MR imaging findings in an autopsy-proven case of selective neuronal necrosis involving the entire left cerebral hemispheric cortex, left thalamus, and contralateral cerebellum following a period of status epilepticus. Imaging findings include diffusion abnormality on diffusion-weighted images and increased intensity on T2-weighted images in the above-mentioned regions of the brain.

fig 1.

24-year-old man who experienced status epilepticus 4 days prior to imaging. A and B, Diffusion-weighted trace images (9999/91.4 [TR/TE], B = 1000 s/mm²) through the levels of cerebellum (A) and thalami (B) show diffusion abnormality involving the right cerebellar cortex (arrows in A), the entire left hemispheric cortex, and the left thalamus (B). The high signal in the right middle fossa (indicated with * in A) is artifactual. C, Spin-echo T2-weighted (2800/80/1 [TR/TE/excitations]) image through the same level as B shows mildly increased intensity in the diffusely thickened left hemispheric cortex and the left thalamus. Note the relative prominence of signal void in middle and anterior cerebral artery branches (arrows) on the left side. D, Fluid-attenuated inversion recovery coronal image (9002/145/2200 [TR/TE/TI]) reveals the right hippocampal ganglioglioma (arrow). Note increased intensity in the left hemispheric cortex. E, Flow-sensitive gradient-echo T1-weighted image (9.3/2.1/90 degrees [TR/TE/flip angle]). Prominent anterior and middle cerebral artery branches (arrowheads) over the left hemispheric cortex suggest enhanced arterial flow in the left hemisphere. F, Histologic section through the left frontal cortex stained with hemotoxylin and eosin shows eosinophilic neurons (short, thick arrows). The surrounding neuropil (indicated with *) is edematous, as demonstrated by expanded perineural spaces (curved arrows), but there is no fragmentation of the neuropil, and glial cells (long arrow) showed no evidence of necrosis or apoptosis. These findings correspond to selective neuronal necrosis.