RESUMEN
<p><b>OBJECTIVES</b>To explore the diagnostic value of color Doppler flow imaging (CDFI) in monitoring portal vein complications (PVC) following orthotopic liver transplantation (OLT).</p><p><b>METHODS</b>Five hundred and four patients received OLT and had CDFI examinations before and after their transplantations. CDFI monitoring parameters before the operation included portal vein diameter, blood flow velocity and the presence of thrombi within the portal vein. Monitoring parameters after the operation included portal vein diameters of donor and receiver sides, and the diameter of the mouth of anastomosis, inner side of blood vessel echo, the direction of blood flow and its speed.</p><p><b>RESULTS</b>Of the 504 patients examined, the median velocity of the portal blood flow was 46.27 cm/s (range: 15.8 to 110.8) on the day of the operation. The blood flow speed of 358 cases (71.03%) was higher than 40 cm/s. Of the 358 patients, 347 (68.85%) had a blood flow speed lower than 40 cm/s one month after the operation. Sixty-four patients (12.70%) showed hepatofugal blood flow once, and only one case had a total hepatofugal blood flow. Thirteen patients (2.58%) had portal vein complications, including 4 cases with portal vein thrombosis and 9 with portal vein stenosis.</p><p><b>CONCLUSION</b>Not all abnormal portal vein blood flow signals will lead to complications. It is worthwhile to monitor the portal blood flows. CDFI plays an important role in the diagnosis of portal vein complications after orthotopic liver transplantation.</p>