Neuromeningeal access for transarterial intravenous carotid-cavernous fistula embolization

Endovascular treatment of the cavernous sinus dural arteriovenous fistula: current status and considerations

A cavernous sinus dural arteriovenous fistula (CS-DAVF) is an abnormal arteriovenous communication involving the dura mater within or near the CS wall. The dural arteries from the internal carotid artery and external carotid artery supply the CS-DAVF, and the superior ophthalmic vein (SOV) and inferior petrous sinus (IPS) are frequent venous drainers. In CS-DAVF cases, high-risk lesions require treatment. Endovascular treatment (EVT) has been the first-line option for CS-DAVFs. To our knowledge, a review of the EVT of CS-DAVFs is lacking. Therefore, in this paper, we review the available literature on this issue. In addition, some illustrative cases are also provided to more concisely expound the EVT of CS-DAVFs. According to the recent literature, transvenous embolization via the IPS is considered the most effective method for EVT of CS-DAVFs. In addition, the transorbital approach is another reasonable choice. Other venous approaches can also be tried. Because of the low cure rate, transarterial embolization for CS-DAVFs is limited to only highly selected patients. In the EVT of CS-DAVFs, various agents have been used, including coil, Onyx, and n-butyl cyanoacrylate, with coil being the preferred one. In addition, when EVT cannot obliterate the CS-DAVF, stereotactic radiotherapy may be considered. In general, despite various complications, EVT is a feasible and effective method to manage CS-DAVFs by way of various access routes and can yield a good prognosis.

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

Background

With the introduction of Onyx, transarterial embolization has become the most common endovascular approach to treating dural arteriovenous fistulas (dAVFs), often via the middle meningeal or occipital arteries. The ascending pharyngeal artery (APA) is a less frequently explored transarterial route because of its small caliber, potential anastomoses to the internal carotid and vertebral arteries, and vital supply to lower cranial nerves.

Objective

To review our institutional experience and highlight the prevalence of APA supply to dAVFs and cases where it is a safe and effective pedicle for embolization.

Methods

We reviewed our endovascular database (January 1, 1996 to March 1, 2016) for cranial dAVFs, evaluating dAVF characteristics and embolization results for those treated transarterially via the APA.

Results

Of 267 endovascularly treated dAVFs, 68 had APA supply (25%). Of these 68 dAVFs, embolization was carried out via this pedicle in 8 (12%) and 7 were ultimately occluded. No complications, including post-treatment cranial neuropathies or radiographic evidence of non-target embolization, were found. For 5 dAVFs, the APA was selected as the initial pedicle for embolization (two marginal sinus, one distal sigmoid, one cavernous, one tentorial). In four of these five cases, dAVF occlusion was achieved via the initial APA feeding artery pedicle. In one case, near-complete, stagnant occlusion was achieved after APA embolization; complete occlusion was achieved after adjunctive embolization of a single additional middle meningeal artery pedicle. In three other cases of complex transverse/sigmoid dAVFs, the APA was used after multiple attempts via middle meningeal and occipital artery pedicles. Occlusion was not achieved transarterially; two of these three dAVFs were ultimately occluded transvenously.

Conclusions

In rare, select cases, the APA is an excellent route for transarterial embolization of cranial dAVFs.