Comparison of nBCA and Onyx for Embolization of Spinal Dural Arteriovenous Fistulas

Background Endovascular embolization can effectively treat spinal dural arteriovenous fistulas (SDAVFs). One factor limiting the success and durability of endovascular treatments is reliably casting and occluding the draining vein. We sought to compare the efficacies of n-butyl-2-cyanoacrylate (nBCA) and Onyx in the treatment of SDAVFs.Methods We retrospectively analyzed patients with SDAVFs treated with endovascular embolization for whether a "durable cure" was achieved, defined as complete obliteration, clinical improvement, and sustained radiologic cure on follow-up. We compared the outcomes of patients treated with Onyx to those treated with nBCA.Results A total of 40 embolizations for SDAVFs were performed in 38 patients. All patients were treated exclusively with liquid embolysates: Onyx alone (n = 22), nBCA alone (n = 16), or nBCA and Onyx combined (n = 2). For 45% (10/22) of patients treated with Onyx only, complete obliteration of the fistula with casting of the vein was not achieved. These patients were referred for microsurgical ligation. For all 16 patients treated with nBCA only, complete obliteration of the fistula was achieved. All 16 patients exhibited a durable cure compared with 11 of 22 patients (50%) in the Onyx-only group (P = 0.002).Conclusion nBCA may be superior to Onyx for the embolization of SDAVFs. nBCA embolization is safe and effective for a subset of SDAVFs. Prospective studies comparing SDAVF treatment strategies are warranted.