Click on Images for Enlarged View
Findings: CT scan demonstrates air within the hepatic portal vein as well as air extending within veins of the mesentery down to the area of the sigmoid colon. There is also air seen within the wall of the sigmoid colon within the left lower quadrant. This is seen on images 1-6.
Diagnosis: Hepatic portal venous gas secondary to small phlegmon and small diverticular abscess involving the sigmoid colon and distal descending colon.
Discussion: Hepatic portal venous gas can be an ominous prognostic sign or can be associated with benign causes. Iatrogenic hepatic portal venous gas as the result of diagnostic or therapeutic procedures is usually benign. Procedures which can cause hepatic portal venous gas include barium enema, colonoscopy, a nasogastric intubation, liver transplantation and umbilical vein catheterization. However, in a patient with hepatic portal venous gas without history of previous diagnostic or therapeutic intervention, there is usually invasion of anaerobic bacteria into the intestinal tract. The prognosis is usually poor . Causes for non-iatrogenic hepatic portal venous gas include mesenteric infarction, enterocolitis, intraabdominal abscess, intestinal obstruction, gastric volvulus, intestinal pneumatosis, neonatal necrotizing enterocolitis, or possibly blunt abdominal trauma.
In patients who have non-iatrogenic hepatic portal venous gas, CT scan is a very sensitive modality for identifying the hepatic portal venous gas. Also, CT scan has been shown to be the most suitable method to identify the underlying cause of hepatic portal venous gas.
References:
Schultze CG, Blum UK, Haag K. Hepatic Portal Venous Gas:
Imaging Modalities and Clinical Significance. Acta Radiologica 36:377-380, 1995.
Submitted by: