Flaming portal vein as a new color Doppler sign of portal gas: report of two cases.

Portal gas is relatively rare, and the majority of reported cases have shown it to have a close relation to bowel diseases. At present, portal exploration usually begins with color Doppler sonography, and clinicians now possess a good understanding of color Doppler findings of a wide spectrum of portal abnormalities. However, the color Doppler sign we present in this article has not been reported before. We report two cases of ischemic bowel disease in which B-mode ultrasound showed multiple hyperechoic spots moving in the portal vein; the color Doppler appearance was as if the portal vein was on fire (flaming portal vein sign). Knowledge of this simple color Doppler sign helps to improve the diagnostic strategies in patients with portal gas.