Liver allograft transplantation: postoperative CT findings.

The CT findings in the abdomen after liver transplantation as seen on 72 examinations in 23 allograft recipients are described. CT was most useful in the evaluation of the gross structural integrity of the allograft and in the detection of extrahepatic fluid collections. Low-density foci within the allograft parenchyma were seen in 10 patients (43%) and were associated with infarction and necrosis, infection, malignancy, and rejection. Localized extrahepatic fluid collections (hematomas, bilomas, and seromas) were present in 16 patients (70%); four of the focal fluid collections detected by CT were infected. Since the nature of these fluid collections could not always be determined by CT characteristics, fine-needle aspiration was sometimes required for a specific diagnosis. Prominence of the portal structures was associated with previous or ongoing episodes of rejection in eight of nine patients, likely reflecting increased resistance to portal flow. CT occasionally showed low, dense, and calcified thrombi in the donor aorta and inferior vena cava. CT also showed biliary obstruction in four patients (17%) without identifying its cause. CT is a noninvasive means of imaging the hepatic allograft recipient; providing data on the hepatic parenchyma, vasculature, and biliary system; and identifying the presence of intraabdominal fluid.