This case demonstrates both classic findings of superior mesenteric vein (SMV) and chronic portal vein thrombosis:

• non-opacification of SMV, small bowel thickening, together with dramatic mesenteric stranding ("misty mesentery") all the way up to the superior mesenteric root
• non-opacification of portal vein, with extensive venous collateral vessels at the level of the portosplenic confluence, hepatic hilum, and along the extrahepatic biliary structures (cavernous transformation)

The development of collateral flow is evidence that these findings are chronic; however, the patient's acute symptoms prompted concern for component of acute ischemia. 

The imaging findings of mesenteric venous insufficiency were confirmed by the operative findings. In this case, it was decided against bowel resection due to high risk of failure and post-operative leak in the context of venous insufficiency.