Classification of acquired lesions of the corpus callosum with MRI

Abstract

MRI has facilitated diagnostic assessment of the corpus callosum. Diagnostic classification of solitary or multiple lesions of the corpus callosum has not attracted much attention, although signal abnormalities are not uncommon. Our aim was to identify characteristic imaging features of lesions frequently encountered in practice. We reviewed the case histories of 59 patients with lesions shown on MRI. The nature of the lesions was based on clinical features and/or long term follow-up (ischaemic 20, Virchow-Robin spaces 3, diffuse axonal injury 7, multiple sclerosis 11, hydrocephalus 5, acute disseminated encephalomyelitis 5, Marchiafava-Bignami disease 4, lymphoma 2, glioblastoma hamartoma each 1). The location in the sagittal plane, the relationship to the borders of the corpus callosum and midline and the size were documented. The 20 ischaemic lesions were asymmetrical but adjacent to the midline; the latter was involved in new or large lesions. Diffuse axonal injury commonly resulted in large lesions, which tended to be asymmetrical; the midline and borders of the corpus callosum were always involved. Lesions in MS were small, at the lower border of the corpus callosum next to the septum pellucidum, and crossed the midline asymmetrically. Acute disseminated encephalomyelitis and the other perivenous inflammatory diseases caused relatively large, asymmetrical lesions. Hydrocephalus resulted in lesions of the upper part of the corpus callosum, and mostly in its posterior two thirds; they were found in the midline. Lesions in Marchiafava-Bignami disease were large, often symmetrically in the midline in the splenium and did not reach the edge of the corpus callosum.

Splenial and White Matter Lesions Showing Transiently-reduced Diffusion in Mild Encephalopathy Monitored with MR Spectroscopy and Imaging

“…Although the corpus callosum may be involved in ADEM, these lesions are nearly always asymmetric. 10,13 Balasubramanya and colleagues showed decreased ADC values without notable increase in Cho/Cr or decrease of NAA/Cr in the acute stage of ADEM 10 findings that might reflect swelling of the myelin sheaths during the initial stage of ADEM.…”

Reversible Splenial Lesion associated with Cellulitis in a Patient with Lymphedema

“…MRI with contrast shows various enhancements of the lesions in ADEM depending on the stages of the acuity [24]. Other differential diagnoses include posterior reversible encephalopathy syndrome (usually hypertension-related and has subcortical white matter lesion), multiple sclerosis (characteristic relapsing-remitting course), MarchiafavaBignami disease (often seen in alcoholism), ischemia (usually irreversible and has vascular territory distributions), diffuse axonal injury (head trauma-related), lymphoma (positive contrast enhancement), and extrapontine myelinolysis (happens with electrolyte abnormality) [25].…”

Clinical Reasoning: A woman with subacute progressive confusion and gait instability

“…Arteriopathies would be the exception to this pattern, such as cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy and Susac syndrome (SS), both of which can diffusely involve white matter structures. 2 With its predominance of myelinated fibers, the corpus callosum is also affected by demyelinating disease, including multiple sclerosis (MS) and acute disseminated encephalomyelitis (ADEM). 1 Callosal lesions in MS tend to be small and involve the inferior aspect.…”

“…These are usually accompanied by other white and deep gray matter lesions. 2 Marchiafava-Bignami disease is a rare hemorrhagic demyelinating disease primarily involving the corpus callosum and classically associated with chronic alcohol consumption. The corpus callosum degenerates and splits into 3 layers, with marked necrosis and eventual cavitation of the central layer.…”