Transient MR Signal Changes in the Splenium of the Corpus Callosum in Rotavirus Encephalopathy: Value of Diffusion-weighted Imaging

Abstract

The authors report serial brain MR findings from a 2-year-old girl with rotavirus encephalopathy. The lesion in the splenium of the corpus callosum showed restricted proton diffusion, suggesting local cytotoxic edema. Diffusion-weighted images demonstrated the lesion more conspicuously than other techniques, such as fluid-attenuated inversion-recovery and T1- and T2-weighted images. The findings were reversible on follow-up MRI obtained 4 days later. Diffusion-weighted MRI is a potentially useful method for detecting early changes of rotavirus encephalopathy, although the mechanism of the restricted diffusion is not clearly identified.

Isolated Reversible Splenial Lesion in Adult Meningitis: A Case Report and Review of the Literature

“…Recently, similar MRI findings have been reported in some patients with mild encephalitis and encephalopathy (5)(6)(7)(8)(9)(10)(11)(12)(13) (Fig. 1).…”

Mild Encephalitis/Encephalopathy With a Reversible Splenial Lesion: Evaluation by Diffusion Tensor Imaging -Three Case Reports-

“…The exact mechanism of transient reduced diffusion is not known, although some theories have been proposed, including vascular distribution, 10) direct viral invasion, 3) and arginine vasopressin suppression. 7,8) In some cases, including our Cases 2 and 3, reversible lesions detected with diffusion-weighted imaging extended into the entire corpus callosum and deep white matter as well as the splenium of the corpus callosum.…”

“…3,5,8,[10][11][12][13] MERS is defined as a radiologically reversible lesion in the corpus callosum involving at least the splenium. Patients with MERS have reversible symptoms such as impermanent conscious disturbance and seizures, and generally recover completely within a week.…”

“…3,5,8,10,12,13) The findings in the early phase disappear mostly within a few days with the resolution of symptoms. 3,5,8,10,12,13) MERS has been increasingly reported, but only one case of MERS has involved decrease in size of the splenial lesion over 5 months in T 2 -weighted imaging. 2) In contrast, most hyperintense lesions on diffusion-weighted imaging with decreased ADC values, including cerebral infarction and contusional lesions due to trauma, are irreversible.…”

Encephalopathy with Isolated Reversible Splenial Lesion of the Corpus Callosum

“…It is unknown why the splenium is involved as an isolated site. The pathogenesis is speculated to involve pathogens or antibodies induced by them that directly damage axons or the myelin sheath in the splenium of the corpus callosum (7,8,10), and the participation of elevated inflammatory cytokines such as interleukin-6 is also postulated in the pathogenesis (7,12). However, these hypotheses remain controversial.…”