Errors in MDCT diagnosis of acute mesenteric ischemia

CT evaluation of bowel wall enhancement in pneumatosis intestinalis: preventing non-therapeutic laparotomies

PURPOSE

To evaluate the diagnostic performance of bowel wall enhancement for diagnosing concomitant bowel ischemia in patients with parietal pneumatosis (PI) diagnosed at abdominal CT.

MATERIALS AND METHODS

From January 1, 2012 to December 31, 2021, 226 consecutive patients who presented with PI on abdominal CT from any bowel segment were included. Variables at the time of the CT were retrospectively extracted from medical charts. CT examinations were blindly analyzed by two independent radiologists. The third reader classified all disagreement of bowel enhancement in three categories: (1) normal bowel enhancement; (2) doubtful bowel wall enhancement; (3) absent bowel wall enhancement. Multivariable logistic regression analysis was performed. Concomitant bowel ischemia was defined as requirement of bowel resection specifically due to ischemic lesion in operated patients and death from bowel ischemia in non-operated patients.

RESULTS

Overall, 78/226 (35%) patients had PI associated with concomitant bowel ischemia. At multivariate analysis, Only absence or doubtful bowel wall enhancement was associated with concomitant bowel ischemia (OR = 167.73 95%CI [23.39-4349.81], P < 0,001) and acute mesenteric ischemia associated with PP (OR = 67.94; 95%CI [5.18-3262.36], P < 0.009). Among the 82 patients who underwent a laparotomy for suspected bowel ischemia, rate of non-therapeutic laparotomy increased from 15/59 (25%), 2/6 (50%) and 16/17 (94%) when bowel wall enhancement was absent, doubtful and normal respectively.

CONCLUSION

Absence of enhancement of the bowel wall is the primary feature associated with concomitant bowel ischemia. It should be carefully assessed when PI is detected to avoid non-therapeutic laparotomy.

Pneumatosis intestinalis in abdominal CT: predictors of short-term mortality in patients with clinical suspicion of mesenteric ischemia

Purpose

Pneumatosis intestinalis (PI) in the bowel wall demonstrated in computed tomography (CT) of the abdomen is unspecific and its prognostic relevance remains poorly understood. The purpose of this study was to identify predictors of short-term mortality in patients with suspected mesenteric ischemia who were referred to abdominal CT and showed PI.

Methods

In this retrospective, IRB-approved, single-centre study, CT scans and electronic medical records of 540 patients who were referred to abdominal CT with clinical suspicion of mesenteric ischemia were analysed. 109/540 (20%) patients (median age 66 years, 39 females) showed PI. CT findings were correlated with surgical and pathology reports (if available), with clinical and laboratory findings, and with patient history. Short-term outcome was defined as survival within 30 days after CT.

Results

PI was found in the stomach (n = 6), small bowel (n = 65), and colon (n = 85). Further gas was found in mesenteric (n = 54), portal (n = 19) and intrahepatic veins (n = 36). Multivariate analysis revealed that PI in the colon [odds ratio (OR) 2.86], elevated blood AST levels (OR 3.00), and presence of perfusion inhomogeneities in other abdominal organs (OR 3.38) were independent predictors of short-term mortality. Surgery had a positive effect on mortality (88% lower likelihood of mortality), similar to the presence of abdominal pain (65% lower likelihood).

Conclusions

Our study suggests that in patients referred for abdominal CT with clinical suspicion of mesenteric ischemia, location of PI in the colon, elevation of blood AST, and presence of perfusion inhomogeneities in parenchymatous organs are predictors of short-term mortality.

Graphical abstract