Mesenteric and hepatic portal venous gas in a woman with pelvic inflammatory disease

Multi-slice CT for diagnosis of acute mesenteric ischemia

Acute mesenteric ischemia (AMI) has an acute onset and a high mortality rate with nonspecific clinical presentation and is difficult to diagnose. In recent years, due to fast submillimeter scanning and subtle three-dimensional reconstruction, 64-row multi-slice CT can distinctly demonstrate the stenosis and occlusion of the mesenteric vessels, assess the alteration of morphology and blood perfusion of the intestinal wall and mesentery, and promptly and accurately diagnose AMI, intestinal infarction and its etiology. Therefore, CT has become the most valuable and first-line diagnostic modality for evaluating patients with suspected AMI. AMI has different and complicated CT findings due to different etiology, pathology, extent, position, as well as with or without mural hemorrhage or infection. In this article, we systematically review the multi-slice CT manifestations of AMI and its diagnostic value in various causes of AMI in different stages.

Portomesenteric venous gas: is gas distribution linked to etiology and outcome?

PURPOSE

To investigate various anatomical locations of portomesenteric venous gas detected by computed tomography (CT) and their relationship with the underlying etiology and the outcome.

METHODS

The study group consisted of 47 cases with evidence of portomesenteric venous gas detected on abdominal CT examinations, 12 cases were identified through a retrospective PACS search, 35 were prospectively included. The presence of gas at specific anatomical locations in the portomesenteric venous vasculature was assessed according to a pre-defined classification: the arcade vessels close to the bowel segments followed by segmental vessels, the superior mesenteric vein, the extra- and intrahepatic portal vein. The etiology of portomesenteric venous gas and its prognosis were assessed by review of surgical reports, histopathology and medical records. Surgery was performed on 30 patients.

RESULTS

Overall 68.1% of cases were of ischemic etiology. Gas present in the arcade vessels was the best indicator for ischemia (sensitivity 93.8%; specificity 70.0%, positive predictive value 90.9%, negative predictive value 77.8%) compared to other locations and the mere presence of portomesenteric gas independent from the location. The overall mortality rate was 53.2%. Only gas in the arcade and segmental vessels were associated with considerably higher mortality rates (65.8% and 75.0%, respectively) and acceptable frequency (occurrence in 80.9% and 59.6%, respectively).

CONCLUSIONS

The study results indicate that the presence of gas at specific anatomical locations in the portomesenteric venous system, namely the arcade and segmental vessels, may serve as strong indicator for ischemic etiology and poor prognosis in the assessment of individual cases.