1 Section of Vascular and Interventional Radiology, Department of Radiology and Medical Imaging, University of Virginia School of Medicine, Charlottesville, Virginia. Electronic address: wilkins@virginia.edu.
2 Department of Interventional Radiology, University of Texas MD Anderson Cancer Center, Houston, Texas.
3 Section of Interventional Radiology, Department of Radiology, MedStar Washington Hospital Center, Washington, DC.