A Case of Isolated Intracranial Rosai-Dorfman Disease Presenting as a Middle Fossa Mass

We report a case of isolated intracranial Rosai-Dorfman disease presenting as a middle fossa mass in a 26-year-old, otherwise healthy man. The patient initially presented with vague neurological symptoms of transient dizziness, nausea, and visual aura. This lead to intracranial imaging showing an extra-axial-enhancing 2.5-cm mass within the anterior, left middle cranial fossa with associated destruction of the lateral and inferior sphenoid bone. Although the finding was felt to be incidental, the lesion’s radiographic characteristics were worrisome for a neoplastic process. Therefore, the patient underwent a left pterional transzygomatic infratemporal approach for resection of the mass. The intracranial portion of lesion was found to be dural based without any pial or arachnoid violation. The infratemporal portion of mass was then followed into the infratemporal fossa with some resection of the pterygoid musculature to obtain clean margins. A gross total resection was achieved without any radiographic evidence of residual lesion. At the time of surgery, frozen section biopsy was thought to be consistent with a histiocytic process, but final pathology showed giant cells in a lymphocytic background consistent with Rosai-Dorfman disease. At 6-month follow-up the patient is at his neurological baseline; there has been no evidence of recurrence and no additional treatment has been required.