Right hepatic vein stenosis at anastomosis in patients after living donor liver transplantation: optimal Doppler US venous pulsatility index and CT criteria--receiver operating characteristic analysis

Abstract

Purpose: To establish optimal Doppler ultrasonographic (US) venous pulsatility index and computed tomographic (CT) criteria for right hepatic vein (RHV) stenosis after living donor liver transplantation (LDLT) and to compare accuracies of these methods by using receiver operating characteristic (ROC) analysis.

Materials and methods: This retrospective study was approved by an institutional review board; informed consent was waived. Eighty patients (48 men, 32 women; mean age, 51.5 years +/- 9.2 [standard deviation]) underwent Doppler US and CT within 8 days of hepatic venography following right lobe LDLT between October 2006 and September 2008. At venography, RHVs were classified into a stenosis or nonstenosis group. At Doppler US, venous pulsatility index was defined as the difference between maximum and minimum frequency shifts divided by maximum frequency shift. At CT, diameters of anastomosis and RHV were measured; percentage of stenosis was calculated. Mean Doppler US and CT parameters in the two groups were compared; ROC analysis was performed.

Results: There were 30 stenotic and 50 nonstenotic RHVs. Mean venous pulsatility index and mean anastomosis diameter were significantly lower and mean percentage of stenosis was significantly higher in the stenosis than the nonstenosis group (P < .001 each). Optimal cutoffs for venous pulsatility index, anastomosis diameter, and percentage of stenosis were 0.16, 3.7 mm, and 47%, respectively. Sensitivity and specificity were 86.7% and 68.0% for venous pulsatility index, 96.7% and 88.0% for anastomosis diameter, and 96.7% and 86.0% for percentage of stenosis, respectively. At ROC analysis, anastomosis diameter (P = .002) and percentage of stenosis (P = .003) were significantly more accurate than venous pulsatility index.

Conclusion: CT is more accurate than Doppler US for RHV stenosis after LDLT, with venous pulsatility index as the sole sonographic criterion. Patients suspected of having RHV stenosis at Doppler US may benefit from CT to reduce unnecessary venography.