Residual Ultrasound-Enhancing Agents Mimicking Portal Venous Gas

Sonographic detection of mobile echogenic foci within the main portal vein and its branches or within the liver parenchyma extending along the portal triads to the periphery of the liver is an alarming finding that has been associated with portal venous gas in the setting of bowel ischemia. Ultrasound-enhancing agents (UEAs) have been widely utilized in abdominal ultrasound for evaluation of organ neoplasms and vascular patency as well as in echocardiography for the evaluation of cardiac function. The appearance of UEAs on abdominal ultrasound can resemble gas like that seen in the portal venous system and liver in patients with bowel ischemia; therefore, UEA residuals should always be a part of the differential diagnosis of echogenic foci when seen on abdominal ultrasounds with preceding recent UEA administration. In this observational study, we present a series of cases with suspected portal venous gas suspicious for bowel ischemia that turned out to be a result of residual or persistent UEA from the recent contrast-enhanced echocardiography. Discussion of this phenomenon and its potential explanation is provided.