Reversible splenial abnormality in hypoglycemic encephalopathy

Abstract

Lesions involving the splenium of the corpus callosum (SCC) have been rarely reported in cases of hypoglycemic brain injury. We identified signal abnormalities in the SCC in three adult patients with hypoglycemic encephalopathy by using diffusion-weighted imaging (DWI) on a 1.5-T MR scanner. Repeat DWI was performed in all patients following a marked clinical improvement, and MR angiography and routine MRI were also performed. We examined each patient's detailed medical history and blood laboratory tests in order to exclude other conditions causing similar SCC abnormalities. Initial DWI was performed during which each patient showed altered mental status that was attributed to profound hypoglycemia. We observed an identical pattern of DWI abnormality characterized by high signals in the SCC with apparent diffusion coefficient reductions that were reversed completely within several days following appropriate correction of hypoglycemia. T2-weighted or FLAIR images also showed no residual lesion in the SCC and MR angiography was normal in all patients. These case reports suggest that the SCC should be added to the list of selective vulnerability to hypoglycemia and that hypoglycemia, in turn, be included in the differential diagnosis of reversible SCC abnormalities.