Effectiveness of Contrast-Enhanced CT Venography 3D Reconstruction for Emergency Surgery in Non-Occlusive Mesenteric...

Nonocclusive mesenteric ischemia (NOMI) is a lethal postoperative complication associated with a dismal prognosis. It generally causes hemodynamic instability, and thus prompt and appropriate management is required for both examination and treatment. We report a case of NOMI that was diagnosed by CT and angiography after cardiac surgery and was successfully treated by enterectomy.

A 59-year-old woman who had been on hemodialysis for 14 years underwent aortic and mitral valve replacement. On POD 16, the patient presented with severe abdominal pain associated with peritoneal signs. Based on the findings of no evident mesenteric occlusion, decreased enhancement in the intestine, and air in the intestinal wall with hepatic portal venous gas on contrast-enhanced CT images, NOMI was strongly suspected. The findings of scattered vascular stenosis in the superior mesenteric artery and poor enhancement of the intestinal parenchyma on subsequent angiography led to a definitive diagnosis of NOMI. Furthermore, the absence of enhancement of the superior mesenteric vein and intestinal parenchyma on the 3D-reconstructed images of the venous phase on enhanced CT, which were obtained after the angiography, led to the diagnosis of intestinal transmural ischemia and a decision for emergency exploratory laparotomy. During the surgery, discontinuous ischemia was observed in the small intestine from approximately 220 cm distal to Treitz's ligament to the proximal side of the transverse colon. Therefore, a right hemicolectomy, partial ileal resection, and ileostomy were performed. New mesenteric ischemia was not observed postoperatively, and the patient was discharged on POD 53 after the laparotomy.

NOMI is a rare but extremely severe disease entity, and its diagnosis is often delayed because it can be asymptomatic. NOMI often causes hemodynamic deterioration, and thus an appropriate therapeutic strategy should be promptly selected. In cases of suspected NOMI, angiography and contrast-enhanced CT are helpful for reaching a definitive diagnosis. In particular, 3D reconstructed images of the venous phase on enhanced CT are very useful for diagnosing intestinal transmural ischemia and reaching a decision for surgical intervention, which is considered feasible unless an intra-arterial vasodilator appears to exhibit its efficacy.