Transvenous Embolization Using Cone-beam CT and 3D Roadmap Function for Dural Arteriovenous Fistulas

Objective: An important point for consistent success in transvenous embolization (TVE) for dural arteriovenous fistulas (AVFs) is considered to be the identification of, and accurate guiding of the catheter to, the shunt point. We performed TVE using cone-beam CT and 3D roadmap function and evaluated its effectiveness and problems.Methods: In 12 procedures of TVE performed in eight patients with dural AVF, we identified the shunt point by cone-beam CT performed intraoperatively using a diluted contrast agent and guided the microcatheter using 3D roadmap function. Only the shunt point was embolized in patients with a localized shunt point.Results: The shunt point could be identified by cone-beam CT in all eight patients, and the shunt point was found to be localized in three patients. The shunt point was approached using intraoperative 3D roadmap function in six patients. 3D images of the affected sinuses and bones were superimposed on fluoroscopic images in four and two patients, respectively. The 12 procedures could be completed without complications in a mean procedure time of 300 minutes with a mean volume of contrast agent of 203.9 mL and a mean radiation dose of 3133 mGy.Conclusion: Cone-beam CT using a diluted contrast agent is considered to have facilitated the identification of the shunt point, and the use of 3D roadmap function to have made decreases in the use of the contrast agent and radiation exposure possible. It also facilitated the confirmation of the arrival of the microcatheter at the shunt point.