B-Flow Sonography for Detecting Portal Venous Stenosis After Liver Transplantation

A case of a patient in his early 60s with a portal vein stenosis after liver transplantation (LTx) detected by sonography in B-flow mode is reported. Two weeks after LTx, the patient developed ascites and severe alteration of liver function tests. Color Doppler (CD) demonstrated a stenosis in the portal vein with a maximum flow of 340 cm/sec. Due to aliasing, correct assessment of stenosis diameter was not possible by means of CD. However, by using the B-flow imaging technique, slow and fast velocities in the pre-, intra-, and poststenotic segment could be detected without aliasing or overwriting. In addition, a second stenosis in the portal vein was identified. For the follow-up outcome of patients, it is essential to detect and treat this complication. After surgical intervention, graft function recovered and postoperative flow measurements showed a normal portal vein flow of 70 cm/sec in the poststenotic segment.