Cavernous venous malformation complicated by a secondary spontaneous arteriovenous fistula of the eyelid.

Periorbital and orbital cavernous venous malformations (CVMs) are low-flow vascular malformations, whereas arteriovenous fistulas (AVFs) represent high-flow vascular malformations. The authors report a case of a 55-year-old female with no history of prior trauma, presenting with a chronic, progressive, painless, pulsatile left upper eyelid mass. Ophthalmic examination revealed a palpable thrill, and orbital imaging suggested a vascular lesion associated with an arteriovenous fistula (AVF) located in the left upper eyelid. Diagnostic cerebral angiography confirmed a composite lesion comprising a CVM with a secondary AVF. The patient was treated with transvenous coil and N-butyl cyanoacrylate (NBCA) glue embolization, transarterial NBCA embolization, and subsequent surgical excision. Histopathological findings were compatible with a complex combined vascular malformation. At 1-year follow-up, the patient remained asymptomatic with no recurrence. This case highlights the importance of considering diagnostic cerebral angiography for highly suspicious high-flow vascular lesions. A multidisciplinary approach is essential for the optimal management of such complex orbital cases.