Rosai–Dorfman disease mimicking subdural hematoma: a case report

Rosia–Dorfman disease (RDD) is a rare benign disease with exceedingly rare neural involvement. In this report, we describe a very rare case of intracranial RDD mimicking a subdural hematoma. The patient presented with headache and a suspected history of head injury. Head computed tomography showed a well-demarcated extra-axial crescentic hyperdense lesion along the right hemisphere convexity, and this lesion was initially mistaken for a subacute subdural hematoma with brain contusion. However, the follow-up examinations during the subsequent month did not show the natural changes characteristic of a subdural hematoma. Thus, a magnetic resonance imaging scan was performed, which showed a crescentic lesion with T1 isointensity, T2 hypointensity, and obvious homogeneous enhancement. Differential diagnoses such as lymphoma and metastases were considered, and surgery was performed. The final histopathologic examination confirmed the diagnosis of RDD. This report describes a rare presentation of RDD. RDD can mimic the appearance of a subdural hematoma and should be considered as a differential diagnosis even in patients with a history of head injury and a “classic” imaging appearance of a subdural hematoma.