Embolization of high-flow craniofacial vascular malformations with onyx

Abstract

Background and purpose: Various techniques and materials have been used for the endovascular treatment of craniofacial high-flow arteriovenous vascular malformations, because their rarity precludes standardization of their treatment. The aim of this retrospective review is to assess Onyx as the primary embolic agent in the treatment of these vascular malformations.

Materials and methods: Six patients with arteriovenous fistulas and 3 with arteriovenous malformations (AVMs) of the head and neck region were treated with intra-arterial (IA)/direct percutaneous injections of Onyx. Adjunctive maneuvers used during embolization included external compression of the arterial feeders or venous outflow (6 patients), balloon assist (4 patients), and direct embolization of the draining vein remote to the fistula site (1 patient). n-butyl-2-cyanoacrylate (n-BCA) was used in addition to Onyx for rapid induction of thrombosis in a large venous pouch (1 patient) and for cost containment purposes (1 patient). Four patients were treated surgically after the embolization.

Results: There were no neurologic complications secondary to the embolization procedure. The arteriovenous shunt was eliminated in all of the fistulous lesions and 2 of the 3 AVMs. The embolization was incomplete in 1 patient with a large AVM who declined further endovascular or surgical procedures. Untoward events included 2 instances of catheter entrapment (of 9 IA injections), blackish skin discoloration necessitating surgical revision in 1 patient, and difficulty of balloon deflation/wire withdrawal during a balloon-assisted embolization.

Conclusion: Onyx appears to be a safe and effective liquid embolic agent for use in the treatment of craniofacial high-flow vascular malformations with distinct advantages and disadvantages compared with n-BCA.

Fig 1.

Patient 1. A, Lateral projection of the left external carotid arteriogram demonstrates a periorbital arteriovenous malformation supplied by the branches of the superficial temporal (black dotted arrow) and internal maxillary arteries (white dotted arrow, middle meningeal branch: white arrow). B, Lateral projection of the left internal carotid arteriogram showing ophthalmic artery contribution to the supply of the arteriovenous malformation. C, Lateral projection of the left internal carotid arteriogram during second session embolization, after completion of the embolization of the external carotid supply discloses the drainage of the ophthalmic supply (marked by the tip of the hemostatic clamp). This drainage vein was selectively punctured and embolized. D, Native image of the venous phase of a postembolization left common carotid arteriogram showing the embolic cast. The defect within the embolic cast denoted with the solid white arrow is the point of balloon inflation. Embolic agent is also noted in the vein draining the ophthalmic supply (white dotted arrow). E, Left common arteriogram after the final session of embolization shows almost total obliteration of the lesion angiographically.

Fig 2.

Patient 6. A, Native radiogram of right external carotid arteriogram in lateral projection reveals a fistulous CHVM supplied by the superficial temporal artery and collateral supply by ipsilateral middle meningeal and occipital arteries. B, The inflated HyperForm balloon is visible (white arrows) on the roadmap capture in lateral projection obtained during embolization; note the retrograde filling of the middle meningeal and occipital collateral supply. C, Postembolization ipsilateral external carotid arteriogram in the same projection demonstrates no evidence of residual arteriovenous shunt surgery.

Fig 3.

Patient 8. A, Anteroposterior projection of a left external carotid arteriogram in Waters projection depicts a fistulous CHVM supplied by the superficial temporal, anterior deep temporal, and middle meningeal arteries. B, Postembolization external carotid arteriogram in anteroposterior projection reveals total obliteration of the lesion.

Fig 4.

Patient 9. A, Lateral projection of the left superficial temporal arteriogram demonstrates a fistulous CHVM; there is attenuated opacification of the draining vein, which projects in between the 2 branches of the artery. B, Floroscopic image captured during percutaneous embolization shows impediment of venous filling by the external compression over the vein with a hemostatic clamp; retrograde filling in numerous arterial pedicles is also noted. C, Postprocedure external carotid injection in lateral projection demonstrated no evidence of a residual lesion. D, Postembolization photograph demonstrates blackish discoloration at the injection site. E, Photograph after resection of the cast on postoperative day 5 shows residual discoloration at the margins of the incision.