MDCT venography in the evaluation of inferior vena cava in Budd-Chiari syndrome: a road less travelled.

OBJECTIVE To assess the role of multidetector computed tomography (MDCT) venography in the evaluation of the inferior vena cava (IVC) in Budd-Chiari syndrome (BCS), its accuracy as compared to digital subtraction venography (DSV) and the potential of this technique to replace venography for the definitive diagnosis of BCS. METHODS Twenty-five suspected cases of BCS were prospectively enrolled in this study and underwent both MDCT venography and DSV. Two observers independently evaluated and graded both the axial and reformatted MDCT images for the presence, site, degree and length of IVC narrowing. The collateral pathways and the hepatic veins were also assessed in all cases. The degree of correlation between MDCT venography and DSV was expressed using Spearman's rank correlation coefficient (Rs). RESULTS There was excellent correlation between MDCT venography and DSV in predicting the presence of stenosis and in grading the degree and length of IVC stenosis (Rs=0.58, p<0.05). Four patients had presence of a web within the IVC and the reconstructed MDCT venography images detected the flap of the membrane in all of them. In three cases of complete obstruction the cranial extent of the obstruction could be determined on the reconstructed MDCT venography images, while double catheter access through the femoral and jugular routes was needed to determine the same on DSV. MDCT venography was significantly more informative in depicting the presence and site of both intrahepatic and extrahepatic collaterals as compared to DSV. CONCLUSION MDCT venography, in the present study, accurately provided information of both conventional CT and IVCgraphy, in the evaluation of the IVC in a non-invasive way. It helped overcome the shortcomings of CT in the evaluation of IVC and was better than DSV for the evaluation of collaterals, calcification and complete IVC obstruction. We suggest that CT venography can be used as a frontline investigation for the diagnosis of IVC obstruction and for planning surgery or percutaneous endovascular intervention.