[A case of neuronal intranuclear inclusion disease with serial MRI changes observed from before onset of forgetfulness].

A 70-year-old woman presented with a 6-year history of cognitive dysfunction, neurogenic bladder, constipation and recurrent vomiting, and gradual worsening of symptoms. At the first admission to our department, she was also found to have hepatic encephalopathy due to intrahepatic portosystemic shunt. Head MRI revealed abnormal signal intensity at the corticomedullary junction, the splenium of the corpus callosum, and bilateral middle cerebellar peduncles on DWI. She was diagnosed with intranuclear inclusion disease (NIID) based on skin biopsy and genetic testing of NOTCH2NLC. In a retrospective review of serial head MRI findings for ten years, abnormal signal intensity at the corticomedullary junction and the splenium of the corpus callosum on MRI existed prior to the onset of cognitive dysfunction, and expanded gradually. For early diagnosis of NIID, it is important to focus not only on the characteristic high signal intensity at the corticomedullary junction, but also on the signal at the splenium of the corpus callosum from the early stage.

[A case of Marchiafava-Bignami disease suggesting vasogenic edema].

A 61-year-old alcoholic man was admitted to our hospital because of disturbance of consciousness. He also exhibited external ophthalmoplegia, diplopia and mild rigidity, but tendon reflex was normal. On brain MRI, diffusion weighted images (DWI) and apparent diffusion coefficient (ADC) map depicted high intensity in the splenium of the corpus callosum. DWI showed high intensity, but ADC map depicted iso-intensity in bilateral precentral gyri. Marchiafava-Bignami disease (MBD) was diagnosed. After intravenous drip of vitamin, his symptoms improved rapidly and the abnormal MRI findings in the splenium of the corpus callosum and bilateral precentral gyri disappeared gradually. MBD is pathologically characterized by demyelination and necrosis in the corpus callosum, which are generally caused by cytotoxic edema. Our case suggests that vasogenic edema may occur at the early stage of the MBD.