Marchiafava-Bignami disease

Look For First

Hyperintense signal in the corpus callosum on T2/FLAIR in the acute phase, classically beginning in the body and extending to genu then splenium
Sandwich sign on sagittal MRI: central callosal involvement with sparing of dorsal and ventral extremes
Symmetric edematous appearance of corpus callosum with characteristic involvement pattern in appropriate clinical context of alcoholism and malnutrition

Key Image Findings

T2/FLAIR hyperintensities in the corpus callosum in the acute phase indicating edema and demyelination
Sagittal MRI demonstrates the characteristic 'sandwich sign' with central layer involvement and relative sparing of dorsal and ventral portions of the corpus callosum
T1-weighted sequences may show hypointense foci within the affected corpus callosum during acute phase
Progressive atrophy of the corpus callosum visible in the chronic phase on follow-up imaging
Subacute phase may demonstrate hypointense focal lesions likely representing hemosiderin deposition
'Ears of the lynx' sign may be identified as a characteristic imaging feature
CT imaging typically shows hypoattenuating regions in the corpus callosum; hemorrhage would appear iso- or hyperattenuating
MR spectroscopy reveals progressive decrease in NAA/Cr ratio with minimum level after several months, followed by partial recovery at approximately 11 months

Differential Diagnosis

Multiple sclerosis with callosal demyelination: occurs in different clinical setting without chronic alcoholism and malnutrition history
Diffuse axonal injury (DAI) to corpus callosum: distinguished by preceding head trauma and different distribution pattern
Callosal infarction: rare due to rich vascular supply of corpus callosum
Transient lesions of the splenium of the corpus callosum: clinically distinct presentation and reversibility

Discussion

Marchiafava-Bignami disease results from deficiency of all eight vitamin B group forms, leading to demyelination and necrosis specifically targeting the corpus callosum

Disease typically progresses from involvement of corpus callosum body distally to genu and splenium, with potential extension into hemispheric white matter, internal capsule, and middle cerebellar peduncle in some cases

The characteristic sandwich sign on sagittal imaging reflects the pathologic process sparing the dorsal and ventral extremities while affecting central layers of the corpus callosum

Hemispheric disconnection syndrome with apraxia, hemialexia, and dementia reflects the functional consequences of corpus callosum demyelination

Early recognition and vitamin B complex supplementation can result in clinical improvement, though some patients may not recover fully

MR spectroscopy shows dynamic changes with progressive NAA decline followed by partial recovery, providing objective biomarker for disease progression and treatment response

Reporting Pearls

Describe the finding as: 'Symmetric hyperintense signal abnormality in the corpus callosum on T2/FLAIR imaging with central layer involvement and sparing of dorsal and ventral extremities (sandwich sign), consistent with demyelination. Pattern progresses from body to genu and splenium. Correlate with clinical history of chronic alcohol use and malnutrition for diagnostic confirmation.' Include description of any acute edema versus chronic atrophy and extent of involvement.

Pitfalls

Misdiagnosis as multiple sclerosis when appropriate clinical context of alcoholism and nutritional deficiency is not considered
Failure to recognize the distinctive sandwich sign may lead to underrecognition of the characteristic central involvement pattern
Isolated splenial lesions may be mistaken for transient splenial lesions or other callosal pathology without recognition of the progression pattern from body through genu to splenium
Hemorrhagic variant with iso- or hyperattenuating appearance on CT may be misinterpreted as acute stroke or trauma rather than Marchiafava-Bignami disease

Marchiafava-Bignami disease

Key Images

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