Management of nonocclusive mesenteric ischemia: Current progress and future direction

Nonocclusive mesenteric ischemia (NOMI) is a life-threatening intestinal hypoperfusion syndrome characterized by mesenteric vasoconstriction or inadequate oxygen delivery without an acute occlusive lesion. Diagnosis is difficult because abdominal manifestations may be absent or nonspecific in critically ill patients, while laboratory abnormalities primarily reflect systemic hypoperfusion. This review provides a multidisciplinary synthesis of epidemiology, pathophysiology, clinical recognition, diagnosis, prognosis, treatment, prevention, and research priorities. Unlike recent reviews centered on interventional radiology, it integrates multiphasic computed tomography angiography, quantitative vessel and bowel-wall assessment, the Homburg-NOMI angiographic score, two-dimensional perfusion angiography, SOFA-based prognostic assessment, medical stabilization, catheter-directed vasodilator therapy, surgery, and the 2025 European Society for Vascular Surgery recommendations into a practical management framework. Current evidence is dominated by retrospective cohorts and small case series, and no randomized treatment trial specific to NOMI has been completed. Quantitative imaging, biomarkers, and risk scores can structure serial assessment, but no single threshold is sufficiently validated to determine treatment independently. Management should prioritize correction of the precipitating low-flow state, rapid imaging, selective angiography when it will alter therapy, and timely surgery for irreversible bowel injury. Standardized definitions, multicenter validation, and prospective comparative studies are required to improve diagnostic timeliness, bowel preservation, survival, and long-term quality of life.