Serial magnetic resonance imaging changes in hypoglycemic encephalopathy.

PURPOSE Reports of serial magnetic resonance imaging (MRI) in hypoglycemic encephalopathy were limited because MRI is not routinely performed in these patients. Here we present one patient with a history of hypoglycemic encephalopathy and discuss sequential neuroimaging findings. CASE REPORT A 53-year-old male mistakenly took oral hypoglycemic agents developed hypoglycemic encephalopathy. Immediate brain diffusion-weighted image (DWI) demonstrated extensive symmetrical hyperintensive lesions over bilateral subcortical white matter. 14 days later, new hyperintensive lesions involving bilateral cerebral cortex were found on DWI, while previous subcortical white matter lesions disappeared. On day 86, diffusion-weighted images abnormalities vanished and diffuse brain atrophy was noted. CONCLUSION Although subcortical white matter involvement in hypoglycemic encephalopathy was occasionally reported in the literature, few report revealed similar serial MRI changes as our case. Although its mechanism is still unknown, it is important to follow sequential images in hypoglycemic encephalopathy. The brain tissue which was normal in early DWI may not necessarily guarantee undamaged.