Transradial approach in the treatment of a sacral dural arteriovenous fistula: a technical note

Abstract

Sacral dural arteriovenous fistulas (SDAVFs) are rare, constituting no more than 10% of all spinal dural fistulas. They are most commonly fed by the lateral sacral artery (LSA), a branch of the internal iliac artery (IIA). Catheterization of this vessel requires either a crossover at the aortic bifurcation in cases of right femoral access or retrograde catheterization from the ipsilateral common femoral artery. We present the case of a 79-year-old man with tethered cord syndrome and a symptomatic SDAVF fed by two feeders from the left LSA. Spinal diagnostic angiography was made exceptionally challenging by an aorto-bi-iliac endograft, and selective catheterization of the left IIA was not possible. The patient could not undergo surgery due to multiple comorbidities, therefore embolization was considered the best approach. The procedure was carried out through a transradial access (TRA) with Onyx and n-butyl cyanoacrylate. The SDAVF was successfully treated and the patient made a full neurological recovery.

Keywords: fistula; liquid embolic material; lumbosacral; spinal cord; spine.

Figure 1

MRI and spinal angiography of a 79-year-old man with a sacral dural arteriovenous fistula (SDAVF). (A) Sagittal T2-weighted MRI of the lumbar spine showing multiple serpiginous flow voids along the posterior surface of the spinal cord (arrowheads). Note the edematous tethered cord (arrow) and an L2 fracture from a recent fall. (B) Pelvic aortogram through a pigtail high-volume injection showing the aorto-bi-iliac graft. The reconstructed iliac bifurcation (arrow) has a 180 degree configuration that did not allow cross-catheterization of the left iliac arteries. Reverse curve catheters could not be reformed due to the edge of the distal end of the left iliac graft (arrowhead). (C) Left common iliac pigtail arteriography demonstrating an SDAVF fed by two feeders from the left lateral sacral artery (arrows). Note the very slow drainage in the enlarged presacral veins directed cranially towards the spinal canal (arrowhead).

Figure 2

Onyx and glue embolization of the fistula. (A) Superselective arteriogram through a 1.7F Apollo microcatheter at the level of the most distal fistulous point (arrowhead) showing extensive cranially-directed venous drainage in the dilated presacral veins. Note the Sofia catheter lodged in the proximal left internal iliac artery (long arrow) and the proximal marker of the detachable tip of the microcatheter (short arrow). (B) Unsubtracted image from a left internal iliac angiogram shows an Onyx cast filling the most distal fistulous feeder (arrowhead). A slightly less radio-opaque glue cast is seen more superiorly within the embolized proximal feeder to the lesion. (C) Left internal iliac arteriogram demonstrating occlusion of the sacral fistula.