Hepatic infarction caused by arterial insufficiency: spectrum and evolution of CT findings.

PURPOSE: To determine the CT imaging appearances of liver infarction due to arterial insufficiency and to attempt to understand reasons for apparent discrepancy of appearance in prior reports.
MATERIALS AND METHODS: Thirty-seven CT examinations from 18 patients with proven hepatic infarction were evaluated for character, location, and evolution of lesions by all investigators, with a consensus interpretation. Etiologies of infarction included posttransplant complication (15), laparoscopic cholecystectomy complication (2), and traumatic arterial injury (1). Proof of hepatic infarction was made by hepatectomy (11), biopsy (1), or clinical course compatible with infarction with angiographic (3) or surgical (3) evidence of hepatic arterial abnormality. In patients without histologic proof of infarction, all lesions seen at CT were considered to be due to hepatic infarction, except those meeting the criteria for hemangioma. In 10 patients, serial examinations were available over 2-180 days and a determination of serial changes in specific lesions was made using a similar image analysis.
RESULTS: Of 55 lesions identified, 53 could be classified into three shapes--wedge-shaped (18), rounded or oval (26), or irregularly shaped low-attenuation lesions paralleling bile ducts (9). The other two lesions were flat hypodense areas along the posterior aspect of the medial left hepatic lobe. Wedge-shaped lesions were peripherally located; rounded lesions were either peripheral (10) or central (26). The caudate lobe was spared except in one patient. Of 16 serially followed wedge-shaped lesions, four evolved into rounded lesions. No rounded lesions became wedge-shaped.
CONCLUSION: Hepatic infarction caused by arterial disease produces a spectrum of CT findings. Prior reported discrepancies in appearance may be due to the small number of cases in each report and the variety of potential imaging appearances,aas well as evolutionary changes.