peripancreatic pseudoaneurysm
Peripancreatic pseudoaneurysm refers to the formation of a pseudoaneurysm around the pancreatic gland. It is a rare but potentially lethal complication .
Epidemiology
Formation of pseudoaneurysm can occur in as many as 10% of cases of pancreatitis. The time interval is variable, ranging from days to years after the acute episode.
Pathology
The most common vessels affected are the splenic and gastroduodenal arteries.
Radiographic features
Dedicated MDCT or MR angiography can depict the pseudoaneurysm as a well-delineated rounded structure originating from the donor artery. High attenuation or high signal intensity thrombus may be seen within the sac on unenhanced CT scans and fat-suppressed T1-weighted MR images.
There may be features of hemorrhagic pancreatitis.
After contrast administration, the sac may fill with contrast material if it is not completely thrombosed. Conventional angiography remains the standard of reference and provides the capability of endovascular management.
Treatment and prognosis
Early detection and management are paramount given the high mortality associated with rupture. Initial treatment can be with thrombin injection to occlude the sac, arterial embolization, or emergency or elective surgery . Mortality rate according to one recent study was around 11% .
Complications
Recognized complications include:
- rupture: can occur into the peritoneum, adjacent hollow organs, pseudocyst, or pancreatic duct (haemosuccus pancreaticus)
- re-bleeding following embolization
Differential diagnosis
- if juxtapancreatic in location, a pseudoaneurysm can mimic a hypervascular pancreatic lesion