MR venography is used to evaluate central veins for patency and extrinsic compression, providing a radiation-free imaging option with four-dimensional flow evaluation. Its operator dependency arises from varying clinical questions and imaging techniques, with indirect and direct methods used based on patient needs. While MR venography is effective for diagnosing central venous disease, it has limitations in assessing heavy metals and may improve with future advancements in direct thrombus imaging.

1. When is MR Venography Useful?
What makes it so Operator
Dependent ?
Constantino S.Peña
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

9. 75 yo with Left Leg Swelling

10. 75 yo with Left Leg Swelling

11. 40 yo with right arm swelling

12. 40 yo with right arm swelling

13. Portal and Mesenteric Veins

14. 14
Portal and Mesenteric Veins

15. 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

17. TR of the Upper Central Veins

18. Paget Schroetter

19. Complex Malformations

20. Pelvic Congestion Syndrome
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21. Pelvic Congestion Syndrome
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22. 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?

23. Possible Imaging Techniques

24. 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

25. 25

26. Blood-Pool Contrast Agents
Gadofosveset- (Ablavar)
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 Intra-vascular half-life of 28 minutes
 Allows steady state imaging for 1
hour
 First agent approved for MRA-
aortoiliac indication

27. MRA MRA/MRV MRV
Blood-Pool Contrast Agents
Gadofosveset- (Ablavar)

28. 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

29. When is CT Venography
better?
 Evaluation of metal stent
 Renal failure (Hemodialysis)
 Pacemaker/AICD

30. 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

31. Thank You!
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