BACKGROUND: The results of treatment of intracranial dural arteriovenous 
fistulas (DAVFs) since Onyx became available as an embolic agent at our 
institution is reported. An algorithm is presented for treatment of DAVFs with 
Onyx, and the role of endovascular transvenous, surgical, and radiosurgical 
approaches are presented.
METHODS: Thirty-two patients with DAVFs treated between November 2005 and 
November 2008 by endovascular embolization, surgery, or radiosurgery were 
identified by a retrospective chart review. Treatment strategies were based on 
the location or complexity of the fistula and the patient's clinical status. 
Data collected included DAVF characteristics, obliteration rates, complications, 
and outcomes. The results were analyzed and correlated with the treatment 
modality.
RESULTS: Presenting symptoms were as follows: hemorrhage (n = 12 patients), 
headaches (n = 12), tinnitus (n = 5), orbital symptoms (n = 7), and seizures (n 
= 1). Thirty patients were treated by endovascular embolization (transarterial 
only with Onyx-21, transvenous only with platinum coils-6, transarterial [Onyx] 
and transvenous [coils]-3). Five patients (4 after incomplete/failed 
embolization) had surgical excision of the fistula. Three patients were treated 
with Gamma Knife radiosurgery (primary-1, 2 after incomplete/failed 
embolization). The locations of the fistulas were transverse sigmoid (10 
patients), petrotentorial (7 patients), indirect carotid cavernous fistula (7 
patients), parasagittal/falcine (3 patients), middle fossa dura (3 patients), 
torcula (1 patient), and anterior fossa dura (1 patient). The distribution of 
patients according to Borden classification was I-6, II-13, and III-13. Complete 
obliteration of the fistula was achieved in 26/32 (81%) patients after 
multimodal treatment. All surgical cases had complete obliteration. In the 
high-risk group with cortical venous reflux, 23/26 (89%) patients were cured. 
Endovascular complications included a stuck microcatheter tip with fracture of 
the tip in two patients and cranial nerves V and VII palsies in one patient. At 
last follow-up (range 1-36 months), 24 patients had modified Rankin score of 
0-2, 5 patients had modified Rankin score of 3-5, and 3 patients were dead. Two 
patients died during admission due to the insult of the hemorrhage, and one died 
after an accidental fall with subsequent traumatic subdural hematoma.
CONCLUSIONS: Multimodality treatment of DAVFs has high success rates for cure at 
our center. Transarterial embolization with Onyx has become the primary 
treatment for intracranial DAVFs at our center and is associated with high 
safety profile and efficacy. Transvenous coil embolization is still preferred in 
DAVFs with supply from arterial branches supplying cranial nerves, predominant 
internal carotid artery feeders and potential extracranial-intracranial 
collateral anastomosis. In our series, patients with incompletely treated DAVFs 
were treated with surgery and those with partially treated type I fistulas had 
radiosurgery for palliation.