Contralateral cerebellar atrophy in Rasmussen’s syndrome: a case report

Introduction Rasmussen's syndrome is a rare and devastating chronic progressive encephalitis, characterized by unilateral brain inflammation, pharmaco-resistant focal epilepsy, and progressive neurological deficit. This case report describes the magnetic resonance imaging (MRI) findings in a 12-year-old child with Rasmussen's syndrome, illustrating the rare feature of contralateral cerebellar atrophy. Case presentation The patient presented with status epilepticus and progressive hemiparesis. Cerebral MRI demonstrated the characteristic lesions of the disease: right hemispheric atrophy, FLAIR hyperintensities of the subcortical white matter, and ipsilateral ventricular enlargement. The notable element was the discovery of left cerebellar atrophy. The diagnosis of Rasmussen's syndrome was established based on the clinical evolution and radiological data. Conclusion This study contributes to medical literature by supporting the pathophysiological hypothesis of trans-synaptic degeneration along the crossed cortico-ponto-cerebellar pathways, secondary to the progressive destruction of the cerebral hemisphere. This case highlights that contralateral cerebellar atrophy should be recognized as a possible manifestation in the advanced evolution of this encephalitis, thus enriching the spectrum of its MRI manifestations and assisting in differentiating the disease from other entities responsible for unilateral cerebral atrophy.