Spontaneous hemorrhage in an intraorbital arteriovenous malformation

Objective: To report the clinical findings and management of spontaneous he morrhage in an unsuspected intraorbital arteriovenous malformation. Design: Interventional case report. Methods: Review of clinical findings, radiologic studies, and treatment of the patient. Results: A 75-year-old woman sought treatment for the rapid onset of severe proptosis, Orbital exploration of a "mass" imaged on computed tomography s can and magnetic resonance imaging resulted in massive intraoperative hemor rhage. Subsequent arteriographic and histopathologic analysis confirmed an underlying orbital arteriovenous malformation. Conclusions: Spontaneous intraorbital hemorrhage from an arteriovenous malf ormation is extremely rare, but should be considered in the differential di agnosis of rapidly progressive proptosis. (C) 2000 by the American Academy of Ophthalmology.