Clinical diagnosis
Case 323
【Progress】
He was transported to backbone hospital where transcatheter arterial embolization could be supplied for management.
【Discussion】
Of all aneurysms, abdomen visceral arteries occur with 0.1 to 0.2% (1-3). Of all abdomen aneurysms, aneurysms of pancreas-duodenum occur with around 2 % (1-3). Pseudoaneurysms of pancreas-duodenum occur more often than true aneurysm and those pseudoaneurysms is presumed to make rupture with 50 – 90% (1-3).
Pseudoaneurysm of pancreas-duodenum area arises from pancreatitis, post-surgery, traumatic injury, and vasculitis (4). Pseudoaneurysm from pancreatitis often occurs in pancreas tail rather than pancreas head (3). Meanwhile, true aneurysm of pancreas-duodenum arises from increase of blood flow by occlusive change of celiac artery, inducing dilatation of pancreas-duodenum arcade with blood pressure burden to branch bifurcation, leading to make aneurysm (5, 6).
Fluids retention of peri-pancreas area, anterior pararenal space, paracolic gutter is often encountered in acute pancreatitis. Hemorrhage from pancreas-duodenum also accumulate in the same area. Then, it is imperative to differentiate between pancreas hemorrhage and pancreatitis liquids. The measurement of CT values of fluids is necessary to distinct them. In short, CT values of fluids from pancreatitis are from 5 to 10 HU, those of hemorrhage are greater than 20HU (4-6).
In our case, CT images depicted fluids retention surrounding duodenum and in retroperitoneal space of anterior para-renal space, mimicking fluids from pancreatitis. However, CT values of the fluids 57.4 HU, indicative of condense of hemorrhage. A few hours later, contrast-enhanced CT depicted a small pseudoaneurysm of pancreas arcade branch artery and increasing volume of hemorrhage.
Treat indication of true aneurysm is its diameter of 2 cm or greater while pseudoaneurysm by pancreatitis is necessary to be treated with no relation of size (5, 6). The managements of pancreas aneurysm are surgery, stent placement and transcatheter arterial embolization (6). For embolization of true aneurysm, isolation and packing are served for pseudoaneurysm, and for that of pseudoaneurysm, principally isolation without packing is done (5, 6). Metallic coils via microcatheter are usually used for isolation and packing. Lately, NBCA-lipiodol is used for embolic material for both of packing and isolation because of instant and rigid occlusion. Our case was transported to core hospital where transcatheter embolization can be supplied.
【Summary】
We presented a fifty-eight-year-old male suffering from sudden abdominal pain. He experienced consistent fever and throat pain for a few days. Laboratory test revealed no abnormal findings except CRP 3.15 mg/dL. Abdomen CT depicted fluid retention surrounding pancreas head and duodenum including anterior pararenal space. Mean CT values of the fluids were 57.4. It is borne in mind that hemorrhage from pancreatic aneurysm rupture mimic fluid retention arising from pancreatitis. Differential point is CT values of fluids: 5 – 10 HU of fluids indicate pancreatic juice from pancreatitis while, 20 HU or more indicates hemorrhage from pseudoaneurysms due to pancreatitis or true aneurysm of arcade branch artery due to celiac artery occlusive change.
【References】
1.Lorelli DR, et al. Diagnosis and management of aneurysms involving the superior mesenteric artery and its branches-a report of four cases. Vasc Endovascular Surg 2003; 37: 59-66.
2.Blumenberg RM, et al. Abdominal apoplexy due to rupture of a superior mesenteric artery aneurysm. Arch Surg1974; 108 :223--226.
3.Stone, WM, et al.: Superior mesenteric artery aneurysms: Is presence an indication for intervention? J. Vasc. Surg 2002; 36: 234-237.
4.Sachdev U, et al. Management of aneurysms involving branches of the celiac and superior mesenteric arteries: a comparison of surgical and endovascular therapy. J Vasc Surg 2006; 44: 718-724.
5.Ikoma A, et al. Inferior pancreaticoduodenal artery aneurysm treated with coil packing and stent placement. World J Radiol. 2012 Aug 28;4(8):387-90.
6.Nakai M et al. Endovascular stenting and stent-graft repair of a hemorrhagic superior mesenteric artery pseudoaneurysm and dissection associated with pancreaticoduodenectomy. J Vasc Interv Radiol. 2012:23(10):1381-4.
2024.1.22