Acute mesenteric ischemia (AMI) is a life threatening diagnosis and a therapeutic emergency with high mortality rates (50-95%). Its diagnosis and management are challenging issues. It is due to arterial thrombosis in 20-30% of cases, emboli in 40-50%, and venous obstruction in 5-20%; non occlusive mesenteric ischemia accounts for 20-30% of cases. Clinical presentation includes severe abdominal pain which contrasts with poor clinical findings, and depends also on the cause. Quick AngioMDCT is the cornerstone of diagnosis, with a reliability of 95.6%: it detects vascular obstruction as well as signs of intestinal ischemia (reduced wall enhancement) or necrosis (pneumatosis intestinalis and/or portal gas) and peritoneal irritation signs. There are no randomized or controlled trials of AMI therapy. Therapeutic options include surgery, with an important morbi-mortality, but also increasingly endovascular procedures such as: -administration of vasodilatators to treat NOMI, -local thromboaspiration and thrombolysis for arterial emboli, -balloon angioplasty ± stenting ± thrombolysis to treat arterial thrombosis and mesenteric complications of aortic dissection, -in situ thrombolysis ± mechanical disobliteration of mesenteric venous thrombosis. Percutaneous endovascular techniques may be valuable alternatives to surgery in selected patients, and can be helpful in limiting bowel resection. Endoscopy is the primary diagnostic and treatment modality in non-variceal upper gastrointestinal haemorrhage (NVUGH). When endoscopy fails to control bleeding embolisation or surgery are the haemostatic options. Placing endoscopic clips at the site of endoscopically uncontrollable haemorrhage facilitates successful embolisation. CT angiography sensitivity in acute bleeding is 90% but this depends on careful case selection. CT is particularly useful when endoscopy fails to identify the site haemorrhage or there is a history of aortic reconstruction or pancreaticobiliary procedure or disease (ACR Appropriateness Criteria 2010). In transpapillary (bile or pancreatic duct) haemorrhage embolisation is the first line intervention. In known site life-threatening post-surgical haemorrhage (e.g. surgical drain bleeding) proceeding directly to angiography expedites haemostasis. The decision making process when endoscopy fails to control NVUGH depends on the available evidence but also on the 24/7 availability of services and/or the speed of response. A recent systematic analysis of embolisation in NVGUH reported pooled mean technical and clinical success rates in primary UGI haemorrhage only, trans-papillary haemorrhage only, and mixed studies were 84% and 67%, 93% and 89%, and 93% and 64%, respectively. The evidence comparing surgery and embolisation is limited to six single-centre cohort studies. Despite decision making bias, with more elderly patients, coagulopathy and other adverse co-morbidities in the embolisation group: mortality, clinical success and re-bleeding were equivalent. Large-volume resuscitation, particularly when clotting derangement or multi-organ failure results, is associated with increased mortality. This reinforces the need for rapid control haemorrhage and has implications for service organisation and delivery. Acute Mesenteric ischaemia (AMI) is a life-threatening vascular emergency due to acute decrease of small bowel blood supply that may present occlusive (arterial/venous) or non-occlusive ethiopathogenesis. It has been estimated that the majority of cases (65%) are caused by arterial embolism or thrombosis, 25% by non-occlusive aetiology and the remaining 10% from venous thrombotic aetiology. Despite the advances in imaging techniques and, consequently, in therapeutic approaches, the overall mortality rate of this condition still ranges from 60 to 100%. An early diagnosis is important for a correct therapeutic approach able to reduce the mortality. Till now the best imaging method in diagnosis of mesenteric ischaemia/ infarction is enhanced CT even if some authors are considering a role for MRI in the evaluation of these disorders. Moreover, in available literature, there exists no systematic evaluation of the radiological findings related to different ethiopathogenesis of AMI and their chronological evolution. The aim of our studies was to identify the macroscopic, microscopic and μ-MRI findings of each aetiology of AMI and to document their chronological evolution in rat models. The progression of the ischaemic disease, observed in these experimental models, appears in line with the human pathology and so it could represent a useful tool to evaluate the role of MRI as an alternative technique in the diagnosis of intestinal infarction. Learning Objectives: