マルキアファーヴァ・ビニャミ病の画像診断

Diagnostic Imaging of Marchiafava-Bignami Disease

マルキアファーヴァ・ビニャミ病はアルコール多飲者に生ずる脳梁の脱髄壊死を特徴とする稀な疾患である。確定診断には剖検が必須であったが，画像診断技術の進歩は生前診断を可能にした。脳梁病変の分布はさまざまで，時に脳梁外病変を伴い，アルコール非乱用者にも生じうることがわかった。今後，画像所見とともに臨床症状や病理所見を併せて検討していくことは，病態の解明および治療法の確立に寄与すると思われる。

Abstract

Marchiafava-Bignami disease (MBD) is a rare alchol related disorder characterized by demyelination of the corpus callosum. Clinical features include impaired consciousness, seizure, dysarthria, limb hypertonus, frontal lobe symptoms in the acute stage and interhemispheric disconnection syndromes in the chronic stage. While autopsy was historically necessary for a definitive diagnosis of MBD, imaging systems such as X-ray computed tomography and magnetic resonance imaging have enabled in vivo diagnosis. We reviewed 91 reported MBD cases additional to our 9 own cases focusing on their imaging. The corpus callosum in MBD has irreversible necrosis secondary to edema and demyelination, often complicated by bleeding in the subacute stage and it becomes atrophic in the chronic stage. The observed patterns of corpus callosal lesions were highly variable, sometimes complicated by extra-callosal lesions in the frontal cortex, white matter, and putamen. Moreover, these lesions are sometimes detected in non-alcoholic patients. Although the underlying causes of MBD are still unknown, investigating its imaging characteristics together with clinical and pathological features will contribute to elucidating its etiology. Furthermore, MBD as an alcohol related disease is linked with neurological emergency presentation. Thus, early diagnosis and treatment are essential.