Teaching Case

68-year-old gentleman complained of upper abdominal discomfort post-laparoscopic cholecystectomy.

A large 5.3 cm splenic artery pseudoaneurysm was found on CT that developed in a patient who had been hospitalised with severe gallstone pancreatitis. The pseudoaneurysm was identified on CT examination performed as part of his investigation for acute pancreatitis. The patient complained of upper abdominal discomfort after having undergone laparoscopic cholecystectomy.

A. In the setting of pancreatitis, splenic artery pseudoaneurysm may result from weakening of the wall by pancreatic enzymes. These enzymes cause a necrotising arteritis with destruction of vessel wall architecture and fragmentation of elastic tissues, leading to pseudoaneurysm formation. A long-standing pseudocyst may induce a pseudoaneurysm, caused by vascular erosion from enzymes within the pseudocyst, direct compression or ischaemia.
B. The patient presented with epigastric and left upper quadrant abdominal discomfort after having an uneventful post-operative period post-laparoscopic cholecystectomy, and CT of the abdomen was performed.
C. A 5.3 cm splenic artery pseudoaneurysm developed in a 68-year-old gentleman who had been hospitalised with severe gallstone pancreatitis. Cross-sectional imaging is crucial in such patients to identify complications
D. The pseudoaneurysm was treated with coil embolisation of the aneurysm sac after percutaneous access through the right common femoral artery. The splenic artery was embolized following selective catheterization of the coeliac trunk. Several coils were deployed in the splenic artery proximal and distal to the aneurysm and also within the aneurysm itself. A check CT angiogram was performed 6 weeks after coil embolisation. This showed that the bulk of the pseudoaneurysm had thrombosed off but that there was still flow in a small part of the pseudoaneurysm.
In a second intervention, the splenic artery was once again selectively catheterized from a right femoral artery approach. Table angiography demonstrated persistent flow through the splenic artery with filling of the aneurysm sac. The efferent artery was identified. Superselective catheterization of the aneurysm sac and efferent artery was performed. Two 5-mm coils were placed in the efferent artery. Three 7-mm coils were placed in the main splenic artery. Completion angiogram showed no flow through the aneurysm sac. A check CT angiogram after 6 weeks showed that the aneurysm was completely thrombosed. A further check CT angiogram one year later showed that the pseudoaneurysm had not recurred. Furthermore, the bulk of the spleen was preserved. The patient was completely asymptomatic and suffered no complications. Open splenectomy is another management option in such patients. However, splenectomy carries mortality and morbidity risks of 1.3% and 9%, respectively.
E. Endovascular treatment of post-pancreatitis splenic artery pseudoaneurysm is a safe and effective way of treating this serious complication. It has an additional advantage in preserving splenic tissue. Post-intervention confirmation of complete thrombosis of the pseudoaneurysm is required to avoid the potentially fatal complications of rupture and bleeding.