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Magnetic resonance venography in the diagnosis of inferior vena cava obstruction in Budd-Chiari syndrome.

OBJECTIVE
To evaluate the informativeness of magnetic resonance venography (MRV) in the diagnosis of different types of inferior vena cava (IVC) obstruction.


PATIENTS AND METHODS
56 patients with IVC obstruction underwent MRV scans. These scans were evaluated for morphology of the obstruction and compared with digital subtraction angiography (DSA) images.


RESULTS
Using DSA, we determined that 47 patients had complete obstruction and 9 had partial obstruction. MRV scans revealed 6 cases of partial obstruction. Using MRV, we determined the morphology of the proximal and distal ends of the complete obstructions in the IVC. We classified our observations into cone, plateau, and irregular subtypes. Both DSA and MRV scans were compared to assess the consistency between two methods. MRV demonstrated high sensitivity (100%) for diagnosing a complete obstruction of the IVC, and its specificity was 66.7%. The positive and negative predictive values of MRV were 94% and 100%, respectively.


CONCLUSIONS
MRV imaging is a valuable alternative to DSA for detection of obstructions in the IVC in Budd-Chiari syndrome, particularly in the distal end, which could expedite the decision making for interventional treatment programmes. However, MRV imaging is less suitable for observing the morphology of the proximal ends of obstructions due to the limitations of the scanning plane and the influence of pseudo shadows.