|Year : 2022 | Volume
| Issue : 4 | Page : 382-385
Giant splenic artery pseudoaneurysm: A masquerader of pancreatic pseudocyst
Ramakrishna Narra1, Sushil K Kamaraju2
1 Department of Radiodiagnosis, Katuri Medical College, Chinnakondrupadu, Andhra Pradesh, India
2 Consultant Radiologist, Kamaraju Diagnostic Center, Guntur, Andhra Pradesh, India
|Date of Submission||02-Oct-2020|
|Date of Decision||23-May-2021|
|Date of Acceptance||23-May-2021|
|Date of Web Publication||17-Mar-2023|
Dr. Ramakrishna Narra
Professor, Department of Radiodiagnosis, Flat No: 30, 5 Floor, Venkatesh Estate Apartment, ½ Chandramoulinagar, Guntur - 522007, Andhra Pradesh
Source of Support: None, Conflict of Interest: None
Splenic artery pseudoaneurysms are a rare complication of pancreatitis and occurs due to erosion and weakening of the vessel wall by enzyme rich peri-pancreatic fluid by the cells or contained within an adjacent pseudocyst. Although pseudoaneurysm rupture associated with pancreatitis is very rare, it has a high mortality rate of up to 40%. Therefore, it is necessary to have a sufficient knowledge of this catastrophic complication to make prompt diagnosis and treatment, that is critical in the management of pseudoaneurysms.
Keywords: Computed tomography, splenic artery, pancreatitis, pseudoaneurysm, pseudcyst
|How to cite this article:|
Narra R, Kamaraju SK. Giant splenic artery pseudoaneurysm: A masquerader of pancreatic pseudocyst. J NTR Univ Health Sci 2022;11:382-5
| Introduction|| |
Splenic artery pseudoaneurysm is a rare complication of pancreatitis and occurs due to the enzyme-rich peripancreatic fluid released by the acinar cells or contained within an adjacent pseudocyst that leads to erosion and weakening of the vessel wall. Even though pseudoaneurysm rupture related to pancreatitis is extremely rare, it has a high mortality rate of up to 40%. Hence, it is mandatory to have adequate knowledge of this catastrophic complication to make a precise diagnosis that is critical in the management of pseudoaneurysms.
| Case Report|| |
A 48-year-old male presented with a history of abdominal pain, discomfort for 6 months that aggravated since the past 1 month. The patient is a known case of chronic pancreatitis, diagnosed 2 years back and underwent conservative management. No history of abdominal trauma or prior surgery was reported by the patient. He was a smoker and alcoholic and not a known case of hypertension/diabetes. On physical examination, there was tenderness in the left upper quadrant. On examination, blood pressure was 120/70 mm Hg and pulse rate was 80/min. All blood examination parameters including the hemogram and liver function tests were normal except for a mild increase in serum amylase level.
Abdominal ultrasonography and computed tomography (CT) scan were performed with a 16-slice CT scanner using a triple-phase protocol. Volume rendering (VR), maximum intensity projection (MIP), and multiplanar reformatted images were acquired by utilizing a workstation.
Abdominal ultrasonography using real-time B-mode and color Doppler was performed. On gray-scale ultrasound, the pancreas appeared hypoechoic with multiple tiny hypoechoic areas (pseudocysts) within the head and body of the pancreas associated with peripancreatic fat standing and a few peripancreatic lymph nodes. The pancreatic duct appeared dilated measuring 12 mm in diameter. Approximately 6.5 cm × 5.0 cm × 4.8 cm well-defined, hypoechoic lesion [Figure 1] was noted in the left upper quadrant adjacent to the tail of the pancreas. On color Doppler, the flow was noted within the lesion showing the classical yin-yang sign seen in the pseudoaneurysms [Figure 2].
|Figure 1: Real-time B-mode ultrasonography image showing a well-defined hypoechoic lesion (white arrow) posterior to the tail of the pancreas|
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|Figure 2: Color Doppler image showing the classic yin-yang sign, indicating bidirectional flow due to the swirling of the blood within the pseudoaneurysm|
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Plain and contrast-enhanced CT was performed with oral and intravenous administration of contrast and using a triple-phase protocol. On plain CT, the pancreas appeared hypodense with significant peripancreatic fat stranding and dilated pancreatic duct measuring 13 mm [Figure 3]. Approximately 6.9 cm × 5.4 cm × 5 cm well-defined, hypodense lesion was noted adjacent to the tail of the pancreas and enhancing splenic artery. On contrast, the arterial phase of the lesion showed intense enhancement. Non-enhancing hypodense area was noted within the lesion representing the thrombus [Figure 4], [Figure 5], [Figure 6]. The diagnosis of splenic artery pseudoaneurysm was considered. Management options including the endovascular techniques of transcatheter embolization of pseudoaneurysm, endovascular stent-graft placement, and open surgical options were considered and the risks of each procedure explained to the patient. However, owing to the large size of the aneurysm and economic constraints, open surgery was considered as the management option.
|Figure 3: Plain CT in axial view, demonstrating a thick-walled round hypodense lesion (asterix) adjacent to the tail of the pancreas|
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|Figure 4: Serial axial sections of the abdomen in arterial phase demonstrating intense enhancement within the lesion, indicating pseudoaneurysm (asterix) arising from the splenic artery (arrow). The surrounding thick hypodense non-enhancing part is consistent with the thrombus within the pseudoaneurysm|
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|Figure 5: Serial post-contrast (arterial phase) multi-planar reformatted images in the coronal plane from anterior to posterior showing pseudoaneurysm (asterix) superior to the tail of the pancreas (arrows)|
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|Figure 6: VR (volume rendering) image showing pseudoaneurysm (white arrow) of the splenic artery|
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Surgery was planned and supraceliac aortic control with resection of the pseudoaneurysm was done. The post-operative period was uneventful, and the patient was discharged.
| Discussion|| |
Splenic artery pseudoaneurysm is a rare complication of pancreatitis. The incidence of pseudoaneurysms is 4–10% of the pancreatitis cases. Even though ruptures of pseudoaneurysms are rare, they have a high mortality rate of 48%. Therefore, an accurate diagnosis of pseudoaneurysm is very important in the management and to reduce mortality. Pseudoaneurysms greater than 5 cm are termed as giant aneurysms. Giant pseudoaneurysms are rare and only a few cases have been reported in the literature to date.
The most common clinical features of splenic artery pseudoaneurysm include abdominal pain, melena, hematemesis, and flank pain whereas most of the true aneurysms are asymptomatic. Some patients may present with hemodynamic collapse because of sudden rupture and bleeding.
Risk factors for pseudoaneurysms include acute or chronic pancreatitis, abdominal trauma, peptic ulcer disease, pseudocysts, post-operative, and iatrogenic causes. Whereas the risk factors for true aneurysms are multifactorial including female preponderance, liver transplantation, cirrhosis, collagen vascular disease, arterial fibrodysplasia, and arteritis.
Pseudoaneurysms occur by the enzyme-rich peripancreatic fluid released by the acinar cells or contained within an adjacent pseudocyst that leads to erosion and weakening of the vessel wall. Pseudoaneurysms contain only adventitia in the wall of the vessel whereas true aneurysms contain all three layers of the arterial wall. The splenic artery aneurysms/pseudoaneurysms are common followed by aortic and iliac aneurysms in the abdomen. But in the case of pancreatitis, the splenic artery is the most common artery to be involved followed by gastroduodenal, pancreaticoduodenal, gastric, and hepatic artery. Pseudoaneurysms should be distinguished from pseudocyst, active hemorrhage, and other pancreatic masses.
The first and valuable modality of choice for diagnosing pseudoaneurysm is ultrasound examination with color Doppler. Advantages include wide availability, portability, inexpensive, no radiation, or renal toxic contrast agent. Ultrasound is useful in the identification of pseudoaneurysm, evaluation of adjacent structures, and complications. Color Doppler depicts the flow within the aneurysm and a typical yin-yang sign. However, it provides limited information about visceral arteries and treatment planning as compared to CT and angiographic evaluation.
Plain CT cannot differentiate a pseudoaneurysm from a pseudocyst, whereas contrast-enhanced CT scan denotes the size, location, and relation of the associated vessel and helps in the differentiation of pseudoaneurysm and pseudocyst of the pancreas. Advantages of CT include non-operator dependence, short acquisition time, and demonstration of associated diseases and adequate details for surgical planning. 3D angiography is preferred for small pseudoaneurysms that are not otherwise detected on CT. On contrast CT, pseudoaneurysms show intense enhancement and follow the blood pool enhancement whereas pseudocysts do not enhance unless infected.,
The management of splenic artery pseudoaneurysms depends on location, the severity of clinical symptoms, and presence of complications. Treatment options include medical management, endovascular embolization, laparoscopy, and open surgery.
Endovascular treatment options include transcatheter embolization, percutaneous injection of collagen, and endovascular stent graft which are recommended for asymptomatic cases and in high-risk patients who are unfit for surgery. Endovascular management has low morbidity and complications when compared to open surgery.
Surgical management comprises aneurysmectomy with end-to-end anastomosis and surgical ligation for proximal aneurysms while in the case of distal aneurysms, aneurysmectomy with splenectomy is preferred. Laparoscopic surgery carries a low risk of mortality compared to open methods. In the present case, as the aneurysm was located proximally, supraceliac aortic control with resection of aneurysm was done.
Complications of pseudoaneurysms include fistulization into the adjacent organs such as the stomach or adjacent bowel and bleeding of the aneurysm.,
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given her consent for images and other clinical information to be reported in the journal. The patient understands that her name and initials will not be published and due efforts will be made to conceal her identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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