1. When is MR Venography Useful? What makes it so Operator Dependent ? Constantino S.Pea Interventional Radiologist Medical Director, Vascular Imaging Baptist Cardiac & Vascular Institute, Miami, Florida Clinical Associate Professor of Medicine, University of South Florida And Florida International University Herbert Wertheim School of Medicine

2. Why MR Venography? Evaluate Central Veins- SVC, IVC, Pelvis Patency and extrinsic compression Allows for a 4 Dimensional Flow evaluation- Time Resolved Imaging Lack of Ionizing Radiation Does not utilize Iodinated contrast 3. 18 yo with Left Leg Swelling and Left DVT 4. 18 yo with left leg swelling and Left DVT First delay Second delay 5. 18 yo with Left Leg Swelling and Left DVT First Day Third Day no Stents 6. 68 yo with Left Leg Swelling and Left DVT 7. 75 yo with Left Leg Swelling 8. 75 yo with Left Leg Swelling 9. 40 yo with right arm swelling 10. 40 yo with right arm swelling 11. Portal and Mesenteric Veins 12. 14 Portal and Mesenteric Veins 13. 4D Vascular MRA Acquiring multiple 3D Volume datasets sequentially Modified 3D Gradient sequence with parallel and/or Keyhole imaging is used to achieve a high temporal frame rate; An initial mask is obtained Morphology and time information acquired Low dose of contrast agent used 14. TR of the Upper Central Veins 15. Paget Schroetter 16. Complex Malformations 17. Pelvic Congestion Syndrome 20 18. Pelvic Congestion Syndrome 21 19. Why is MR Venography Operator Dependent? What is the clinical question? What is the best way to study? What type of sequence and contrast material? 20. Possible Imaging Techniques 21. Techniques for MRV Indirect MRV- (recirculation) Injecting upper extremity vein Allowing first pass through the arterial tree Imaging venous system during venous phase Direct MRV Injecting extremity of choice with dilute contrast material 22. 25 23. Blood-Pool Contrast Agents Gadofosveset- (Ablavar) 26 Intra-vascular half-life of 28 minutes Allows steady state imaging for 1 hour First agent approved for MRA- aortoiliac indication 24. MRA MRA/MRV MRV Blood-Pool Contrast Agents Gadofosveset- (Ablavar) 25. Future Technique Direct Thrombus Imaging Endogenous contrast from methemoglobin T1W sequences High signal seen up to 6months in DVT Limitation in the abdomen (run additional PCV) 20 minutes whole body scan 26. When is CT Venography better? Evaluation of metal stent Renal failure (Hemodialysis) Pacemaker/AICD 27. Summary MR Venography has a role in the diagnosis and surveillance of central venous disease. Indications include: SVC/IVC patency, compressive syndromes, portal vein or visceral vein patency. Usually performed when treatment is being considered MR Venography eliminates radiation risk associated with CTV but is limited in terms of heavy metal evaluation (bones and metal) Off-label use of blood pool MR agents will likely allow first pass as well as steady imaging to improve resolution and evaluation of compressive effects Future MR imaging with Direct thrombus imaging may deliver a manner to assess for VTE without radiation or contrast agents 28. Thank You! 31