[Solitary fibrous tumor of the fourth ventricle: case report].

A rare case of solitary fibrous tumor, located wholly within the fourth ventricle, is reported. A 57-year-old male presented with headache and nausea. The preoperative magnetic resonance images revealed a well circumscribed mass in the fourth ventricle that exhibited a low intensity on T1-weighted images and homogeneously enhanced with gadolinium. Vertebral angiogram revealed a tumor stain supplied from the choroidal branches of the posterior inferior cerebellar artery. The tumor was totally resected through a midline suboccipital approach. Histologically, the tumor was composed of spindle-shaped cells growing in fascicles within a collagenous matrix. Immunohistochemical staining demonstrated vimentin and the CD34 positivity of tumor cells. Solitary fibrous tumor is a newly described entity, which should be considered in the differential diagnosis for dural-based lesions.