Gas in the Portal Venous System

In the past the visualization on a roentgenogram of a branching gas pattern overlying the liver shadow has usually been assumed by the radiologist to be indicative of gas in the biliary tree due to biliary fistula or other biliary tract disease. In recent years, however, there have appeared two reports of gas in the portal venous system, a condition which roentgenographically closely mimics gas in the bile passages. Wolfe and Evans (4) first reported the condition in 1955. They had a series of 6 cases in infants. All were proved at autopsy, and in 4, roentgenograms showed the gas pattern. More recently Susman and Senturia (3) described the first case in an adult and suggested a criterion for differentiating gas in the portal vein from gas in the biliary tree roentgenographically. The purpose of this paper is to evaluate further the criterion of Susman and Senturia and to report 3 more cases in which gas was demonstrated in the portal venous system. Susman and Senturia state that gas in the biliary tree is limited to the larger central radicles while gas in the portal venous system fills the finer radicles extending outward nearly to the liver capsule. For this they offer the logical explanation that filling of the biliary tree by gas is hindered by the constant centripetal flow of bile, while filling of the portal venous system is enhanced by the centrifugal flow of blood. In order to validate this criterion, a number of portal venograms and T-tube cholangiograms done in this department have been analyzed. While these examinations are not directly analogous to gas embolization, it was nevertheless felt that positive results would lend credence to the criterion previously mentioned. The outcome of this study tended to confirm the hypothesis. In no instance of biliary tract opacification (T-tube cholangiogram) did the opaque substance come closer than approximately 2 cm. to the liver capsule, as visualized on an anteroposterior film. All of the normal portal venograms on the other hand revealed the opacified venous radicles extending outward almost to the capsule (Fig. 1). The only exceptions to this finding were in patients with severe liver disease and portal hypertension (e.g., cirrhosis) with very poor filling of the intrahepatic portion of the portal vein. Case Reports Case I: J. S., a 19-year-old white female, inmate of a state hospital for mental defectives, was referred to the Indiana University Medical Center because of abdominal distention. She had been given prostigmine, Demerol, and oxygen by the referring physician. She was herself unable to give any information. Physical Findings: The patient appeared critically ill, and the initial examiner recorded “phenomenal abdominal distention.” The abdominal wall was so extremely taut that palpation of abdominal contents was not possible. The remainder of the physical examination was not remarkable except for spastic quadriplegia.