- Always abnormal
- Present when intestinal permeability increases or when there is increase in intestinal luminal pressure
- Neonatal necrotising enterocolitis, adults with gastric emphysema, intestinal obstruction, infection, Crohn disease
- Blunt abdominal trauma, invasive malignancies (colon, ovarian carcinoma)
- Duodenal perforation at ERCP
- Colitis following barium enema
- Gas radiates out of hilum
- Less gravity dependence than pneumobilia, more peripheral distribution
- US: moving gas bubbles in portal vein. Aliasing artifacts on spectral display.
- CT and radiograph: evident when enough gas accumulates and is seen in periphery of liver
Faberman, Robert S., and William W. Mayo-Smith. “Outcome of 17 patients with portal venous gas detected by CT.” AJR. American journal of roentgenology 169.6 (1997): 1535-1538.
Sisk, Phillip B. “Gas in the portal venous system.” Radiology 77.1 (1961): 103-107.
Liebman, PAUL R., et al. “Hepatic–portal venous gas in adults: etiology, pathophysiology and clinical significance.” Annals of surgery 187.3 (1978): 281.