Neuroradiologic findings in scleroderma in “coup de sabre”

A 6-year-old child presents with seizures. He presents a lineal band of soft tissue atrophy in right frontoparietal region.

Emergency department requested an unenhanced brain CT, which in the axial plane demonstrates a focal subcortical calcification in the frontal right lobe. A 3D reconstruction of head surface was performed.

After managing seizures, a brain MRI was requested. Axial T2WI shows blurring of the grey-white interface, sulcal effacement and cortical thickening of the right hemisphere.  Also, a white matter subcortical hyperintensity is seen. Axial FLAIR shows white matter subcortical lesion in the right hemisphere. Frontal atrophic skin lesion is also shown.

T1-weighted post-contrast image demonstrates focal enhancement of white matter in the right parietal lobe.

Background

Morphea is a form of localized scleroderma that affects mostly the skin. Is a rare disease with an estimated annual incidence of 2.7 per 100,000, with a prevalence of 50 per 100,000. Active morphea lesions are characterized by erythema and induration, and of note, most lesions of morphea have an insidious course and are asymptomatic. Inactive lesions show sclerosis and atrophy of the epidermis, dermis, and subcutaneous tissues.

Linear scleroderma, also known as scleroderma “en coup de sabre”, is a subset of localized scleroderma, which is more frequent in pediatric patients.

“En coup de sabre” is a French expression that alludes to the appearance of a frontoparietal lesion as if the patient had been struck by a sabre.

Clinical Perspective

Lateralized linear atrophic band involving soft tissues of  frontoparietal scalp. Neurological symptoms usually appear after the development of the skin lesion. Seizures are the most frequent symptom. Other symptoms include focal neurologic deficits and movement disorders, which can be secondary to brain lesions, trigeminal neuralgia, masticatory spasms, behavioural changes, or progressive intellectual deterioration due to cerebral hemiatrophy.

Imaging Perspective

The band of soft tissue atrophy in the frontoparietal region is visible in brain CT or MRI. The bone below can also be affected.

Neuroimaging findings in the cerebral hemisphere are typically ipsilateral to the skin lesions.

Calcifications are frequent findings, and they typically involve the basal ganglia, thalami, dentate nuclei, and, less often, subcortical white matter.

MRI usually exhibits T2 hyperintensities, mostly in the subcortical white matter, but also in the corpus callosum, deep grey nuclei, and brain stem.

Cerebral atrophy is generally focal and subtle, but it can be more extensive, always affecting the ipsilateral cerebral hemisphere. It is characterized by blurring of the grey-white interface, sulcal effacement, cortical thickening, and abnormal gyral pattern.

An enhanced MRI of control can be done to evaluate the progression of the lesions in the brain. However, the disease usually has a benign course.

Take Home Message / Teaching Points

Think in neuroradiological findings in linear scleroderma in “coup de sabre”.