Background Budd-Chiari syndrome (BCS) is a rare disease with portal hypertension caused by the blockage of thehepatic vein and/or the inferior vena cava (IVC).Angiography is the“golden standard”for diagnosis,but it is an invasiveexamination.To assess the diagnostic value of a fresh blood imaging (FBI) relative to BCS,we used a magneticresonance angiography (MRA) with an FBI sequence for a preoperative evaluation of the BCS patients in this study.Methods Fifty patients who were suspected of having BCS after they had been checked by a B-ultrasound werestudied.2D and 3D FBI were performed on a 1.5T superconductive MR scanner.Original images were rebuilt using amaximal intensity projection (MIP) method on the console.Two doctors reviewed all images before they learned of theangiography results.We then compared the diagnoses obtained from the FBI and angiography results to evaluate thediagnostic value of the FBI.Results Forty-one patients were diagnosed as BCS and 9 as non-BCS based on an angiography.The FBI correctlydiagnosed 38 patients,incorrectly diagnosed 1 patient,and missed diagnosis in 3 patients.Thus,the diagnosticsensitivity of the FBI is 93% (38/41),the specificity is 89% (8/9) and the accuracy is 92% (46/50).The FBI images of the13 membranous stenoses of the IVC showed a sudden stenosis of the post-liver segment of the IVC.The Images of the 5patients with a membranous obstruction of the IVC showed IVC thickening and an absence of blood signals in thepost-hepatic segment of the IVC.The images of the 4 patients with the segmental thrombosis of the IVC showedabnormal and intermittent signals in the IVC.The images of the 6 patients with a simple hepatic vein obstruction showedobstructive hepatic veins.The images of the 6 patients with the stenosis of both the IVC and the hepatic veins showedthe stenosis of the IVC,the thickening of the hepatic veins and the formation of a compensatory circulation within the liverLastly,the images of the 7 patients showed a combination of the IVC thrombosis with stenosis or with the obstruction ofone or two hepatic veins.Conclusions An FBI can show a membranous stenosis,and an obstruction and thrombosis of the IVC.In addition,itcan also demonstrate the thickening of the flexural hepatic vein and the development of intra-hepatic compensatorybranches with slow blood flow.Thus,it can guide the puncturing and opening of the hepatic vein involved in aninterventional therapy for BCS patients. Background Budd-Chiari syndrome (BCS) is a rare disease with portal hypertension caused by the blockage of the hepatic vein and / or the inferior vena cava (IVC). Angiography is the “golden standard ” for diagnosis, but it is an invasive feature .To assess the diagnostic value of a fresh blood imaging (FBI) relative to BCS, we used a magneticresonance angiography (MRA) with an FBI sequence for a preoperative evaluation of the BCS patients in this study. Fifty patients who were suspected of having BCS after they had been checked by a B-ultrasound were staged.2D and 3D FBI were performed on a 1.5T superconductive MR scanner.Original images were rebuilt using amaximal intensity projection (MIP) method on the console.Two doctors reviewed all images before before they learned of the angiography results. Then then the diagnoses obtained from the FBI and angiography results to evaluate the diagnostic value of the FBI. Results Forty-one patients were diagnosed as BCS and 9 as non-BCS based on an The diagnostic sensitivity of the FBI was 93% (38/41), the specificity is 89% (8/9) and the accuracy is 92% (46/50). The FBI images of the 13 membranous stenoses of the IVC showed a sudden stenosis of the post-liver segment of the IVC. The Images of the 5patients with a membranous obstruction of the IVC showed IVC thickening and an absence of blood signals in the post-hepatic segment of the IVC. The images of the 4 patients with the segmental thrombosis of the IVC showed normal and intermittent signals in the IVC. The images of the 6 patients with a simple hepatic vein obstruction showed obstructive hepatic veins. images of the 6 patients with the stenosis of both the IVC and the hepatic veins showed the stenosis of the IVC, the thickening of the hepatic veins and the formation of a compensatory circulation within the liver Lastly, the images of the 7 patients showed a combination of the IVC thrombosis with stenosis or with the obstruction of one or two hepatic veins. Conclusions An FBI can show a membranous stenosis, and an obstruction and thrombosis of the IVC. additionally, itcan also demonstrate the thickening of the flexural hepatic vein and the development of intra-hepatic compensatory branches with slow blood flow. Thus, it can guide the puncturing and opening of the hepatic vein involved in an interventional therapy for BCS patients.