Clinical course ;  Patient had IPMN, and 1cm lesion in duodenum

Duodenum 3rd/4th portion enhancement 1cm nodular lesion R11; no change of size,

 T2 intermediate SI

-       Diagnosed at subepithelial tumor such as GIST, neuroendocrine tumor

-       PPPD was done and duodenal lesion was revealed as Dilated submucosal vein,

-                  consistent with venous malformation, duodenum.

Vascular malformation

1.     Low-flow vascular malformations

- Capillary malformation

- Venous malformation

- Lymphatic malformation

2.     High-flow vascular malformations

- Arterial malformation

- Arteriovenous malformation

- Arteriovenous fistula

3.     Combined vascular malformation (combination of above lesion types)

The most common site of AVM is the cecum and right colon (78%), followed by the jejunum (10.5%), whereas only 0.9% of all AVMs are found in the pancreas. The cause of pancreatic AVM is thought to be congenital in 90% of cases, and 10% to 30% of pancreatic AVM are associated with Osler-Weber-Rendu disease. Several cases of acquired pancreatic AVM occurred because of pancreatitis, trauma, and tumors.

After enhancement, early contrast filling of the enlarged portal venous system was seen in the arterial phase. In addition, demonstration of enhancement of the lesion, commensurate with the aorta, on contrast enhanced multiphasic imaging is helpful in diagnosing pancreatic AVM

Characteristic signal void on T1- and T2-weighted imaging could provide the diagnostic clue for  AVM. This signal void is a characteristic of rapid blood flow.

However, slow flow lesion shows atypical signal in MRI.

MR features of vascular malformation.