Dural arteriovenous fistulas of the occipital sinus secondary to trauma: Two case reports and a review of the literature.

BACKGROUND

Intracranial dural arteriovenous fistulas (DAVFs) involving the occipital sinus (OS) are rare vascular anomalies characterized by abnormal connections between meningeal arteries and venous sinuses or cortical veins. Trauma and venous hypertension are recognized factors in the pathogenesis of DAVFs, with previous injuries to the venous sinus and subsequent angiogenic responses contributing to abnormal arteriovenous shunt formation. The OS's variable anatomy and deep midline location add unique challenges to the diagnosis and treatment of DAVFs in this region.

CASE DESCRIPTION

We report two cases of OS DAVFs in patients with a history of remote cranial trauma. The first case describes a 36-year-old man with a 3-year history of progressive headache, recently worsening with severe headache, nausea, and vomiting. Imaging revealed a DAVF at the OS with cortical venous reflux. After an unsuccessful attempt at transarterial embolization, transvenous embolization achieved near-complete obliteration, and the patient remained asymptomatic at the 3-year follow-up. The second case involves a 54-year-old man with a history of a high fall. He initially presented with bilateral leg numbness and urinary retention, progressing to quadriparesis. Imaging demonstrated an OS DAVF with spinal venous congestion and cervical cord compression. Following an unsuccessful transarterial approach, he underwent a suboccipital craniotomy with OS ligation. Despite complete obliteration, he remained significantly disabled at the 1-year follow-up.

CONCLUSION

These cases highlight the role of trauma in the development of OS DAVFs and the challenges associated with their management. Successful treatment often requires a combined approach due to complex arterial feeders and venous drainage patterns. Early intervention is crucial in preventing irreversible neurological deficits caused by prolonged venous congestion, emphasizing the need for timely diagnosis and individualized treatment strategies for DAVFs involving the OS.