Dural Arteriovenous Fistula at the Anterior Condylar Confluence

Abstract

<jats:p> We reviewed the records of eight patients with a dural arteriovenous fistula (DAVF) close to the hypoglossal canal and determined the angioarchitecture of the clinical entity at the anterior condylar confluence. </jats:p><jats:p> Eight patients with DAVF received endovascular treatment at our institute over the past five years. Imaging with selective three-dimensional angiography and thin-slice computed tomography were used to identify the fistula and evaluate the drainage pattern. </jats:p><jats:p> Based on the angiographic findings, the ascending pharyngeal artery was the main feeder in all cases, and the occipital, middle meningeal, posterior auricular, and posterior meningeal arteries also supplied the DAVF to varying degrees. Contralateral contribution was found in five patients. The main drainage route was the external vertebral plexus via the lateral condylar veins in four patients, the inferior petrosal sinus in three patients, and the internal jugular vein via the connecting emissary veins in one patient. Selective angiography identified the shunt point at the anterior condylar confluence close to the anterior condylar vein. Shunt occlusion with transvenous coil packing was performed in all cases; transarterial feeder embolization was also used in three patients. Two patients treated with tight packing of the anterior condylar vein developed temporary or prolonged hypoglossal palsy. </jats:p><jats:p> Based on our results, the main confluence of the shunt is located at the anterior condylar confluence connecting the anterior condylar vein and multiple channels leading to the extracranial venous systems. To avoid postoperative nerve palsy, the side of the anterior condylar vein in the hypoglossal canal should not be densely packed with coils. Evaluating the angioarchitecture using the selective three-dimensional angiography and tomographic imaging greatly helps to determine the target and strategy of endovascular treatment for these DAVF. </jats:p>

Republished: Vertebral–venous fistula: an unusual cause for ocular symptoms mimicking a carotid cavernous fistula

“…A variety of devices, including detachable balloons, and transarterial or transvenous coils are used to occlude the fistula while attempting to maintain the patency of the vertebral artery 6–9. Our case report involved venous drainage into the anterior condylar confluence, which is the pathway for causing ocular symptoms, due to involvement of the inferior petrosal sinus10 11 In an extensive review, Spittau et al elegantly depicted the pathophysiology and treatment of hypoglossal canal dural arteriovenous fistulas, which may present with ocular symptoms similar to our case. Due to the complexity of the arterial–venous connections, a transjugular approach was the most commonly used treatment method, reserving transarterial treatment for lesions without venous access 12.…”

The road less traveled: transarterial embolization of dural arteriovenous fistulas via the ascending pharyngeal artery

“…Marginal sinus fistulas, also referred to as condylar, foramen magnum, and hypoglossal canal fistulas, are a heterogeneous group of lesions; patients with these lesions may present with tinnitus, ocular symptoms in the context of reflux into the cavernous sinus or ophthalmic vein, or even with venous hypertension or hemorrhage if cortical venous drainage is recruited (figure 1A, B) 8–10. Traditionally, these fistulae required surgical disconnection11 or were managed via transvenous approaches 8 9. In an endovascular series of 14 marginal sinus dAVFs, 11 were noted to drain into a sinus first with or without cortical reflux; all were treated successfully without complication via transvenous approaches 8.…”

Transvenous Embolization of Dural Arteriovenous Fistulas of the Hypoglossal Canal: Report of Three Cases and Review of the Literature

“…The transvenous embolization leads to the highest rate of clinical cure at a relatively low therapeutic risk. There are some reports showing that overpacking the ACV may result in hypoglossal nerve palsy due to mass effect on the hypoglossal nerve as in our first case presented [3, 8, 9]. The damage to the hypoglossal nerve can be permanent [3, 8, 18] or transient [8, 16, 20].…”

“…Symptoms include headaches [2, 4], tinnitus [2, 5-7], hypoglossal nerve palsy [2, 3, 8], bruit [1, 9], diplopia [6, 10], proptosis and chemosis [1, 4, 6, 9, 10], hoarseness [11], vocal cord palsy [11], intracranial hemorrhage [12], and congestion myelopathy [2, 12]. …”