[Reversible splenial lesion of the corpus callosum on diffusion-weighted magnetic resonance imaging in hypoglycemic hemiparesis: report of two cases].

Hypoglycemic hemiparesis is rare and can be misdiagnosed as cerebral infarction or transient ischemic attack. Early diagnosis of these two disorders is critical because, if not treated with prompt glucose administration, hypoglycemia may lead to a fatal clinical course. We reported two cases of hypoglycemic hemiparesis with a reversible splenial lesion on MRI. The first case was a 69-year-old woman presenting with dysarthria and right hemiparesis. The second case was a 60-year-old man presenting with right hemiparesis. Plasma glucose level was 39 mg/d/ and 32 mg/d/, respectively. In both cases, initial diffusion-weighted imaging (DWI) showed hyperintensity lesions with decreased apparent diffusion coefficient (ADC) values in the splenium of the corpus callosum. Following appropriate correction of hypoglycemia, repeat DWI showed complete resolution of hyperintensity lesions with normalized ADC values. These findings can provide complementary information in the differential diagnosis of hypoglycemic hemiparesis and stroke, though underlying pathophysiological mechanisms are still elusive. We emphasize that checking plasma glucose level is necessary even in cases with hemiparesis. Furthermore, we should be aware that not every hyperintensity lesion on DWI is due to ischemia. There are times when it could be due to hypoglycemia.