A "pseudo-cavernoma" - an encapsulated hematoma of the choroid plexus.

We present the first report of an intraventricular encapsulated hematoma, mimicking cavernous malformation on imaging and gross lesion appearance. A 47-year-old female on anticoagulation therapy for atrial fibrillation presented with left upper extremity apraxia, neglect, and mild gait imbalance. Her brain CT scan and MRI revealed multilobulated lesions involving the choroid plexus in the atria of both lateral ventricles. The intraoperative appearance was that of encapsulated mass, with blood clots at different stages of liquefaction and organization, all consistent with the gross appearance of a cavernous malformation. However, histopathologic examination demonstrated hematoma with components at different ages, and normal vessel infiltration without any hint of cavernous malformation histology, or underlying neoplasia. Encapsulated hematoma should be considered in the differential diagnosis of hemorrhagic intraventricular masses.