Portal Venous and Mesenteric Gas

Mesenteric and Portal Venous Gas
This elderly patient presented with abdominal pain. CT demonstrated extensive mesenteric, mural and portal venous gas. The patient passed away shortly after admission to the emergency department.

Portal venous gas is merely the accumulation of gas in the portal vein and its branches. It needs to be distinguished from pneumobilia, although this is usually not too problematic, when associated findings are taken into account along with the pattern of gas (peripheral in portal venous gas (see axial image here), central in pneumobilia).

Although traditionally considered a harbinger of death, portal venous gas is increasingly recognised in a variety of conditions, many of which do not carry as high mortality or morbidity.

Causes of portal venous gas are best divided according to the age of the patient (Children / Infants and Adults).

In adults causes can be divided into:
Alterations of bowel wall:
– Ischaemic bowel (usually mural gas as well as mesenteric gas – mortality of 75 – 90% – but gas is not an independent predictor)
– Necrotic / ulcerated Colorectal carcinoma (CRC)
– Inflammatory bowel disease (IBD)
– Perforated peptic ulcer
Bowel luminal distention:
– iatrogenic gastric and bowel dilatation
– acute gastric dilatation
Intrabdominal sepsis:
– diverticulitis
– cholecystitis
– cholangitis
Other:
– pneumatosis intestinalis
– COAD
– corticosteroid use

For more information please visit Radiopaedia.org here.

References:

1. RL Eisenberg “Gastrointestinal Radiology: A Pattern Approach” Lippincott Williams & Wilkins
2. C Sebasti√ɬ† et al “Portomesenteric Vein Gas: Pathologic Mechanisms, CT Findings, and Prognosis” Radiographics. 2000;20:1213-1224.

Credit: Dr Frank Gaillard