CT Diagnosis and Differentiation Between Primary Hepatic Vein Budd-Chiari Syndrome and Hepatic Sinusoidal Obstructive Syndrome

Objective: The clinical and laboratory specificity for diagnosing primary hepatic vein Budd-Chiari syndrome (BCS) and hepatic sinusoidal obstructive syndrome (SOS) is limited. This study aims to explore the application of contrast-enhanced CT in the differential diagnosis of BCS and SOS by examining their clinical and imaging features. Materials and Methods: Clinical and imaging data from 26 patients diagnosed with BCS via DSA and 20 patients diagnosed with SOS via liver biopsy were retrospectively analyzed. The differences between the two groups were compared. Results: Portal hypertension-related symptoms were more prominent in 16 patients with BCS, and the diameter of the hepatic artery, portal trunk, and degree of splenic vein dilation were all greater than those in 11 patients with SOS. On contrast-enhanced CT, BCS exhibited a patchy enhancement pattern in the portal phase, primarily localized to the first hepatic portal and caudate lobe. In contrast, SOS showed a “crow's claw-like” heterogeneous enhancement pattern centered on the second hepatic division. Liver function injury in BCS patients was less severe than in SOS patients. Elevated alkaline phosphatase, increased total cholesterol, and decreased albumin levels were more pronounced in SOS patients compared to those with BCS. A common feature in both groups was the absence or faint visibility of the three hepatic veins in the venous phase. Conclusion: The CT findings of BCS and hepatic SOS exhibit certain specificities. The enlargement of the caudate lobe and the degree of collateral circulation are key factors in the CT-based differential diagnosis. Notably, the heterogeneous enhancement pattern of BCS centered on the first hepatic portal and the heterogeneous enhancement pattern of SOS centered on the second hepatic portal in contrast-enhanced CT are valuable for the early differential diagnosis of these conditions.