Objective: The aim of this study is to describe the technique and results of the transvenous approach for occlusion of cavernous dural arteriovenous fistulas (DAVFs) with Onyx. Methods: Eleven patients presenting with clinically symptomatic DAVFs, were treated between August 2005 and February 2007 at Beijing Tiantan Hospital. We were able to navigate small hydrophilic catheters and microguidwires through the facial vein or inferior petrosal sinus (IPS) into the ipsilateral cavernous sinus. After reaching the fistula site the cavernous sinus was packed with Onyx or combining with detachable platinum coils. Results: We were able to reach the fistula site and to achieve a good packing of Onyx or combining with coils within the arteriovenous shunting zone in 10 patients. The final angiogram showed complete occlusion of the arteriovenous fistula. Two (18.2%) patients developed a bradycardia during DMSO injection. No complications related to the approach were observed. Conclusions: Transvenous occlusion of cavernous DAVFs is a feasible approach, even via facial vein or via ITS. Onyx may be another option for cavernous packing other than detachable platinum coils. (C) 2008 Elsevier Ireland Ltd. All rights reserved.