Orbital hemangiopericytoma--a case report.

A 50-year-old male presented with progressive proptosis in the right eye for 10 years. Decreased visual acuity to hand-motion level was also noted. Orbital computed tomography revealed a large homogenously enhanced mass lesion in the right retrobulbar region with optic nerve compression. The remainder of the ocular examination was normal, except for right mature cataract. The tumor was completely removed through lateral orbitotomy. Histologic findings showed a picture of hemangiopericytoma. One month after cataract extraction and intraocular lens implantation in the right eye, the patient had restored vision. Through 2 years' follow-up, no more orbital tumor was noted. Orbital hemangiopericytoma may have potentially malignant behavior, and a high local recurrence rate if incompletely excised. Complete, intact removal prevents tumor recurrence and provides a good result.