Magnetic resonance (MR) evaluation of dilated pelvic veins: what the vascular and interventional radiologist needs to know

Learning Objectives 1. Identify various clinical conditions which cause pelvic venous dilatation and/or obstruction. 2. Describe the anatomic abnormality associated with each clinical condition and provide MR and correlative conventional angiographic examples of each abnormality. 3. Discuss the utility of MR angiography in planning potential endovascular interventions for such venous abnormalities, with a specific focus on the use of blood pool contrast agents in MR angiography. Background Recently developed MR blood pool contrast agents, such as gadofoscecet (Ablavar™), have markedly less extracellular distribution than their predecessors, a property that allows for steady-state high-resolution imaging of veins and complex venous lesions. In this presentation, we will illustrate how gadofoscecet use enhances the MR characterization of venous anomalies and abnormalities. Improved MR characterization facilitates not only proper diagnosis of but also the appropriate planning for endovascular interventions which treat pelvic vein obstruction. Clinical Findings/Procedure Details We will present MR and correlative conventional angiography examples of venous anomalies and abnormalities resulting in pelvic venous dilatation and/or obstruction, including: congenital caval anomalies, inferior vena cava stenosis stenosis from chronic iliocaval thrombosis, May-Thurner (Cockett) syndrome, nutcracker syndrome, gonadal vein reflux, venous obstruction secondary to mass effect from extrinsic anatomic structures. Conclusion and/or Teaching Points (1) Pelvic venous dilation is commonly caused by venous anomalies or abnormalities which can be diagnosed noninvasively using MR angiography. (2) MR blood pool contrast agents, such as gadofoscecet (Ablavar™), enhance MR characterization of venous anomalies and abnormalities by opacifying their full geographic extent as well as providing information regarding directionality of venous flow. (3) MR angiography is a useful, if not critical, tool in pre-procedure planning of endovascular treatment of pelvic vein obstruction.