Endovascular treatment of a craniocervical junction dural arteriovenous fistula associated with lateral medullary syndrome: A case report

Abstract

Intracranial dural arteriovenous fistulas (DAVFs) with drainage into the perimedullary veins have been reported to cause brainstem and spinal hemorrhages, subarachnoid hemorrhages, and progressive myelopathy. However, there have been no reports of craniocervical junction arteriovenous fistulas (CCJ-AVFs) complicated by lateral medullary syndrome (LMS) and subsequently treated. We present a case successfully treated with transvenous and transarterial embolization. A 67-year-old man presented with headache and dizziness was diagnosed with left LMS based on diffusion-weighted MRI. MRA ruled out vertebral artery dissection and posterior inferior cerebellar artery occlusion but suggested an arteriovenous shunt at the CCJ, which digital subtraction angiography confirmed as a DAVF fed by the radiculomeningeal artery with drainage into the anterior lateral spinal vein and deep brainstem veins. To minimize embolic complications, transvenous embolization with coils was performed first, followed by transarterial embolization with N-butyl cyanoacrylate. Postoperative MRI showed resolution of venous engorgement, and the patient was discharged without additional neurological deficits. This case highlights the potential role of AVF-induced venous engorgement in brainstem infarction and underscores the importance of early diagnosis and individualized treatment. A combined transvenous and transarterial approach can effectively control ascending venous outflow while minimizing procedural risks.

Keywords: Brainstem infarction; Craniocervical junction; Dural arteriovenous fistula; Endovascular treatment; Lateral medullary syndrome.

Fig. 1

(A) Axial diffusion-weighted MRI showing a lesion with restricted diffusion in the left lateral medulla. (B) Axial MR angiographic image at the level of the second cervical vertebra. A white arrow indicates abnormal vessels extending from the epidural space toward the spinal cord. (C) MR angiographic image with the bilateral internal and external carotid arteries digitally subtracted. A white arrowheads indicates a vessel arising from the left vertebral artery, coursing medially and then ascending to the superior petrosal sinus.

Fig. 2

(A) An anterior-posterior view of left vertebral angiography demonstrates a radiculomeningeal artery arising from the V3 segment and extending medially, forming an arteriovenous fistula with venous drainage observed both superiorly and inferiorly. Image quality in the surrounding area was partially degraded due to digital subtraction artifacts caused by a dental metal crown. (B) 3D rotational angiography of the left vertebral artery demonstrates a radiculomeningeal artery (white arrow) forming a fistulous connection with the anterior lateral spinal vein, with clear visualization of the venous drainage routes. Bilateral lateral medullary veins and lateral pontine veins are visualized, with marked dilation observed on the left side. The venous drainage proceeds via the superior petrosal sinus and petrosal vein into the basal vein of Rosenthal. (C) Axial fused image of heavily T2-weighted MRI and 3D rotational angiography of the left vertebral artery. The white arrowhead indicates the shunt point. Based on the vessel caliber change observed on the dura mater, the lesion was diagnosed as a dural arteriovenous fistula (DAVF). (D) Coronal fused image of heavily T2-weighted MRI and 3D rotational angiography of the left vertebral artery, with vascular structures rendered in red. The white arrowhead indicates the shunt point located on the dura mater.

Fig. 3

(A) Selective angiography of the radiculomeningeal artery arising from the left vertebral artery demonstrates venous drainage reaching the anterior lateral spinal vein via the internal jugular vein and superior petrosal sinus. (B) The left anterior lateral spinal vein was embolized with 7 coils via a transvenous approach. (C) Cone-beam CT performed via the left vertebral artery after coil embolization reveals persistent perimedullary venous enhancement in the arterial phase, indicating incomplete occlusion of the shunt.

Fig. 4

(A and B) Left vertebral angiography following coil embolization of the anterior lateral spinal vein is shown (A). A microcatheter was advanced into the C2 radiculomeningeal artery, through which 50% diluted N-butyl cyanoacrylate was administered (B). The black arrowhead indicates the tip of the microcatheter. (C) Following arterial embolization angiography of the left vertebral artery demonstrates disappearance of the ascending draining vein previously observed preoperatively. Minimal residual flow into the anterior spinal vein was noted during the arterial phase. (D and E) An infarct in the left lateral medulla is observed on diffusion-weighted imaging (A), and a corresponding lateral medullary vein (LMV) is visualized at the same location on axial MR angiography (MRA) (white arrow, D). On postoperative MRA, the signal from the LMV observed preoperatively is no longer visualized (white arrow). The hypointensity lesion in the left lateral medulla represents changes consistent with chronic infarction.