[Orbital hemangiopericytoma: a case with involvement of the intraconal space].

PURPOSE/METHODS: We report a case of orbital hemangiopericytoma, in a 14 year-old boy. Neuroradiological findings, including those of computerized tomography (CT), magnetic resonance imaging (MRI), and ultrasonography are detailed.

RESULTS/CONCLUSIONS: Diagnostic imaging showed a well-circumscribed and solid mass with an intraconal location. The tumor was grossly purple, richly vascularized and encapsulated. The histological study revealed a hemangiopericytoma of borderline grade with hypercellularity and moderate number of mitotic figures. We emphasize the rarity of the orbital hemangiopericytoma specially when it is located within the muscle cone.