Doppler ultrasound follow-up of middle hepatic vein tributaries-interposition vessel graft in recipients of living donor liver transplantation using modified right lobe grafts

Objective: To investigate the value of Doppler ultrasound (US) in recipients of living donor liver transplantation (LDLT) using modified right-lobe grafts (mRLGs) with obstruction of the middle hepatic vein tributaries (MHVTs)-interposition vessel graft (IVG). Methods: This study included 240 consecutive LDLT recipients in whom 564 MHVTs (>5mm) were reconstructed using IVG. Regular follow-up Doppler US was performed to assess the patency of the MHVTs-IVG and, if there was an obstruction, to evaluate for the establishment of collateral drainage. MHVTs with obstruction were subdivided into those with and without intrahepatic veno-venous collaterals on Doppler US and were correlated with CT scans. Results: MHVTs-IVG obstruction was identified in 137 patients with 227 MHVTs on follow-up Doppler US (6.2 +/- 4.7 months). 90 patients with 149 MHVTs in whom the time interval between Doppler US and contrast-enhanced dynamic CT scans was <1week were classified into either collateral (68 patients with 121 MHVTs) or non-collateral (22 patients with 28 MHVTs) groups. The presence of intrahepatic veno-venous collaterals on Doppler US were significantly related to no remarkable hepatic venous congestion on CT by both perpatient and per-vein analyses (66 of 68 patients (97.1%) and 118 of 121 MHVTs (97.5%), p < 0.001 and p < 0.001, respectively). Conclusion: On Doppler US follow-up of LDLT recipients using mRLGs, identification of intrahepatic veno-venous collaterals associated with obstruction of MHVTs-IVG suggests no remarkable hepatic venous congestion. Advances in knowledge: When an obstruction of a MHVTs-IVG is encountered on Doppler US follow-up of LDLT recipients using mRLGs, no further evaluation with CT is warranted if intrahepatic veno-venous collaterals