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DOI:10.2214/AJR.06.0794
AJR 2007; 188:992-999
© American Roentgen Ray Society

Review

Splenic Artery Aneurysms and Pseudoaneurysms: Clinical Distinctions and CT Appearances

Gautam A. Agrawal1, Pamela T. Johnson and Elliot K. Fishman

1 All authors: Department of Radiology, Johns Hopkins School of Medicine, 601 N Caroline St., Rm. 3251, Baltimore, MD 21287.

Received June 16, 2006; accepted after revision September 12, 2006.

 
Address corresondence to P. T. Johnson (pjohnso5{at}jhmi.edu).

CME This article is available for CME credit. See www.arrs.org for more information.

FOR YOUR INFORMATION

This article is available for CME credit. See www.arrs.org for more information.


Abstract
Top
 Abstract
Introduction
 Incidence
 Pathophysiology
 Clinical Presentation
 Diagnosis
 CT Appearance and Pitfalls
 Treatment and Management
 Conclusion
 References
 
OBJECTIVE. Aneurysms of the splenic artery are being diagnosed with greater frequency as incidental findings on cross-sectional imaging. Splenic artery pseudoaneurysms are even more rare than true aneurysms. This article reviews the clinical features and management of splenic artery aneurysms and pseudoaneurysms. A variety of cases are presented to show the range of CT appearances.

CONCLUSION. Radiologists who identify either type of splenic artery lesion should recognize the clinical and pathophysiologic distinctions between these two forms of splenic vascular pathology and understand the differences in management.

Keywords: abdomen • angiography, CT • pancreatitis • spleen


Introduction
Top
 Abstract
 Introduction
Incidence
 Pathophysiology
 Clinical Presentation
 Diagnosis
 CT Appearance and Pitfalls
 Treatment and Management
 Conclusion
 References
 
The splenic artery is the third most common site of intraabdominal aneurysms after aneurysms of the abdominal aorta and the iliac arteries [1]. The true prevalence is unknown, with estimates varying widely, from 0.2% to as high as 10.4% [2, 3]. Although they were once thought to be rare, with wider use of cross-sectional imaging, splenic artery aneurysms are being diagnosed with increasing frequency as incidental findings [4]. As uncommon as true splenic artery aneurysms are, pseudoaneurysms are even more rare, with fewer than 200 cases reported in the English-language literature [5]. Radiologists who identify these vascular pathologies must recognize the clinical significance and understand the management. This article reviews the clinical features, CT appearance, and management of splenic artery aneurysms and pseudoaneurysms.


Incidence
Top
 Abstract
 Introduction
 Incidence
Pathophysiology
 Clinical Presentation
 Diagnosis
 CT Appearance and Pitfalls
 Treatment and Management
 Conclusion
 References
 
Beaussier [6] reported the first case of splenic artery aneurysm in 1770 at necropsy. These relatively uncommon lesions are being incidentally detected with greater frequency as a result of the widespread use of high-resolution imaging techniques. The true prevalence data are widely varying, from 0.098% in a large autopsy series to 0.78% in a study of 3,600 arteriograms to 10.4% in an autopsy series on patients 60 years or older with special attention given to the splenic artery [2, 3, 7]. Splenic artery aneurysm is four times more common in women but approximately three times more likely to rupture in men [8].

In contrast to splenic artery aneurysm, splenic artery pseudoaneurysm (Fig. 1) is rare. In a large series from the Mayo Clinic, 10 splenic artery pseudoaneurysms were compiled over 18 years [5]. To date, fewer than 200 cases have been reported in the English-language literature.


Figure 1
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  		Fig. 1 —Schematic of normal splenic artery, splenic artery aneurysm, and pseudoaneurysm. In true aneurysm, wall is composed of intima (I), media (M), and adventitia (A); in comparison, pseudoaneurysm wall contains only intima and media. In setting of pancreatitis, splenic artery pseudoaneurysm may result from weakening of wall by pancreatic enzymes [5]. (Illustration by Frank Corl)

 


Pathophysiology
Top
 Abstract
 Introduction
 Incidence
 Pathophysiology
Clinical Presentation
 Diagnosis
 CT Appearance and Pitfalls
 Treatment and Management
 Conclusion
 References
 
Although the precise etiology of splenic artery aneurysm remains unknown, it has been associated with hypertension, portal hypertension, cirrhosis, liver transplantation, and pregnancy [8-10]. Less commonly associated conditions include arterial fibrodysplasia, arteritis, collagen vascular disease, {alpha}1-antitrypsin deficiency, and inflammatory and infectious disorders [8]. In contrast to aneurysms of larger vessels such as the aorta, atherosclerosis is not considered to be the underlying cause. Histopathologically, 80-99% of splenic artery aneurysms reveal atherosclerosis; however, this is probably a secondary process occurring from primary degeneration of the media [1, 4, 11].


Figure 2
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  		Fig. 2 —44-year-old woman undergoing evaluation as potential renal donor with no significant medical history. Arterial phase contrast-enhanced CT scan shows 2-cm distal splenic artery aneurysm located near splenic hilum, which was confirmed with arteriography.

 


Figure 3
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  		Fig. 3 —78-year-old man with history of treated bladder cancer who presented with persistent hematuria. Arterial phase contrast-enhanced CT scan reveals 2-cm aneurysm arising from mid portion of splenic artery.

 


Figure 4
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  		Fig. 4A —63-year-old woman with splenic artery aneurysm detected 2 years previously who is being evaluated for stability. Axial arterial phase contrast enhanced CT scan (A) and sagittal oblique multiplanar reformation (B) show 1.8-cm aneurysm with dense peripheral calcification. Aneurysm appeared unchanged since prior examination.

 


Figure 5
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  		Fig. 4B —63-year-old woman with splenic artery aneurysm detected 2 years previously who is being evaluated for stability. Axial arterial phase contrast enhanced CT scan (A) and sagittal oblique multiplanar reformation (B) show 1.8-cm aneurysm with dense peripheral calcification. Aneurysm appeared unchanged since prior examination.

 
True aneurysms of the splenic artery are usually smaller than 3 cm, ranging from 2 to 9 cm in one series of nine cases [11]. They may be multiple and are most commonly located in the distal portion of the artery (Fig. 2), although they can arise from other segments of the splenic artery (Fig. 3). Peripheral calcification (Fig. 4A, 4B) is common; Dave et al. [11] reported that 80% show atherosclerotic changes including calcification, and mural thrombus may be present (Fig. 5).


Figure 6
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  		Fig. 5 —50-year-old woman with history of Gaucher's disease and incidentally discovered splenic artery aneurysm on CT. Axial arterial phase contrast-enhanced CT scan shows 2.2-cm, partially thrombosed, peripherally calcified aneurysm (arrow) arising from distal splenic artery.

 
The causes of splenic artery pseudoaneurysm include pancreatitis (Fig. 6A, 6B), trauma, iatrogenic and postoperative causes, and, rarely, peptic ulcer disease [5]. In the case of pancreatitis, pancreatic enzymes are thought to cause a necrotizing arteritis with destruction of vessel wall architecture and fragmentation of elastic tissues, leading to aneurysm or pseudoaneurysm [12]. In addition to direct damage of vascular structures by the spread of pancreatic enzymes from severe inflammation, Flati et al. [13] described another mechanism by which pancreatitis related pseudoaneurysms can form. A longstanding pseudocyst may induce a pseudoaneurysm, caused by vascular erosion from enzymes within the pseudocyst, direct compression, or ischemia [13].


Figure 7
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  		Fig. 6A —48-year-old man with chronic pancreatitis and 2- to 3-day history of abdominal pain. Axial late arterial phase contrast-enhanced CT scan (A) and volume-rendered image (B) show 3 x 2.5 cm partially thrombosed pseudoaneurysm (arrow) adjacent to tail of pancreas, probably secondary to previous pancreatitis. Pseudoaneurysm was treated by interventional coil embolization.

 

Figure 8
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  		Fig. 6B —48-year-old man with chronic pancreatitis and 2- to 3-day history of abdominal pain. Axial late arterial phase contrast-enhanced CT scan (A) and volume-rendered image (B) show 3 x 2.5 cm partially thrombosed pseudoaneurysm (arrow) adjacent to tail of pancreas, probably secondary to previous pancreatitis. Pseudoaneurysm was treated by interventional coil embolization.

 

A combination retrospective case series and literature review reported that the mean size of splenic artery pseudoaneuryms was 4.8 cm (range, 0.3-17 cm) [5]. Those authors noted that a coexisting pseudocyst was present in 41% of cases. Secondary hemor-rhage from pseudoaneurysms may involve the pancreatic duct, peritoneum, retroperitoneum, adjacent organs (stomach, colon), or a pseudocyst if one is present [5, 13].


Clinical Presentation
Top
 Abstract
 Introduction
 Incidence
 Pathophysiology
 Clinical Presentation
Diagnosis
 CT Appearance and Pitfalls
 Treatment and Management
 Conclusion
 References
 
Clinically, most splenic artery aneurysms are asymptomatic. A large series from the Mayo Clinic showed that 97.5% of patients with nonruptured splenic artery aneurysms were asymptomatic [8]. Early reports of splenic artery aneurysm suggested the risk of rupture is 10% [14]. However, more recent data suggest rupture rates closer to 2-3% [15, 16]. The frequency of rupture is increased with liver transplantation, portal hypertension, and pregnancy [17]. Typical clinical presentations of ruptured splenic artery aneurysm include abdominal pain (Fig. 7A, 7B, 7C), hemodynamic instability, and gastrointestinal bleeding. The sudden onset of left upper quadrant pain usually indicates rupture has occurred [17]. There can be spontaneous stabilization and subsequent sudden circulatory collapse. This is termed the "double rupture" phenomenon, whereby initial bleeding tamponades into the lesser sac, followed by flooding into the peritoneal cavity [18].


Figure 9
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  		Fig. 7A —45-year-old man who presented with syncope due to spontaneous, intraperitoneal hemorrhage while exercising, source of which was not identified during surgical exploration or by postoperative CT angiography at outside institution. Axial early venous phase image (A) and sagittal multiplanar reformation (B) from IV contrast-enhanced MDCT reveal 2.5-cm aneurysm posterior to pancreas and adjacent residual retroperitoneal and intraperitoneal hemorrhage.

 

Figure 10
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  		Fig. 7B —45-year-old man who presented with syncope due to spontaneous, intraperitoneal hemorrhage while exercising, source of which was not identified during surgical exploration or by postoperative CT angiography at outside institution. Axial early venous phase image (A) and sagittal multiplanar reformation (B) from IV contrast-enhanced MDCT reveal 2.5-cm aneurysm posterior to pancreas and adjacent residual retroperitoneal and intraperitoneal hemorrhage.

 

Figure 11
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  		Fig. 7C —45-year-old man who presented with syncope due to spontaneous, intraperitoneal hemorrhage while exercising, source of which was not identified during surgical exploration or by postoperative CT angiography at outside institution. Axial oblique volume rendering from superior viewing orientation shows relationship of pseudoaneurysm to splenic artery. Aneurysm and splenic artery were successfully embolized.

 

Unlike splenic artery aneurysms, splenic artery pseudoaneurysms (Fig. 8A, 8B) will nearly always present with symptoms. In a large review of the literature, only 2.5% of cases presented incidentally [5]. The most common presentations are abdominal pain (29.5%), hematochezia or melena (26.2%), hemorrhage into the pancreatic duct (20.3%), and hematemesis (14.8%) [5]. The risk of rupture of a splenic artery pseudoaneurysm can be as high as 37%, with the mortality rate approaching 90% when untreated [19, 20]. Furthermore, both small and large pseudoaneurysms are at risk for rupture [5]. Prompt diagnosis and treatment are therefore critical in the management of these patients.


Figure 12
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  		Fig. 8A —38-year-old woman with history of chronic pancreatitis who had known pancreatic pseudocyst. Contrast-enhanced CT showed enlarging splenic artery pseudoaneurysm. Axial (A) and coronal volume rendering (B) from IV and oral contrast-enhanced venous phase MDCT reveal 4.6 x 3.3 cm heterogeneous mass (white arrows) in region of pancreatic tail. Central enhancing component is compatible with pseudoaneurysm surrounded by acute hemorrhage. In addition, elongated, enhancing region was identified extending from pseudoaneurysm into spleen (black arrows, B), which was new from previous examination and interpreted as second pseudoaneurysm. Patient underwent interventional coil embolization of pseudoaneurysm and the spleen.

 

Figure 13
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  		Fig. 8B —38-year-old woman with history of chronic pancreatitis who had known pancreatic pseudocyst. Contrast-enhanced CT showed enlarging splenic artery pseudoaneurysm. Axial (A) and coronal volume rendering (B) from IV and oral contrast-enhanced venous phase MDCT reveal 4.6 x 3.3 cm heterogeneous mass (white arrows) in region of pancreatic tail. Central enhancing component is compatible with pseudoaneurysm surrounded by acute hemorrhage. In addition, elongated, enhancing region was identified extending from pseudoaneurysm into spleen (black arrows, B), which was new from previous examination and interpreted as second pseudoaneurysm. Patient underwent interventional coil embolization of pseudoaneurysm and the spleen.

 

Diagnosis
Top
 Abstract
 Introduction
 Incidence
 Pathophysiology
 Clinical Presentation
 Diagnosis
CT Appearance and Pitfalls
 Treatment and Management
 Conclusion
 References
 
Direct catheter angiography has been assumed to be the gold standard for the diagnosis of splenic artery aneurysm and pseudoaneurysm. The high spatial resolution of digital subtraction angiography allows imaging of small vessels, and treatment can be performed concomitantly. However, this procedure requires arterial puncture, with its associated complications. The use of gray-scale and Doppler sonography for the diagnosis of splenic artery aneurysms has been reported [21]. This technique is operator-dependent and may be limited due to obesity, shadowing from bowel gas, and arteriosclerosis [22]. In addition, small lesions can be missed on sonography because of limited spatial resolution [23]. MRI and MR angiography techniques have also been described, with improvements in spatial resolution compared to sonography [23]. Limitations of MRI included its contraindication in patients with pacemakers or aneurysm clips, those suffering from claustrophobia, and those unable to hold their breath [23].

With current MDCT technology, patients can be imaged quickly during the arterial phase, which is essential for detecting these lesions. Relative contraindications to CT angiography include renal failure, poor IV access, and allergy to contrast material. Current generation MDCT scanners are capable of high spatial resolution and short breath-hold times. The high temporal resolution facilitates acquisition of data during a purely arterial phase and results in decreased motion artifact. For creation of 2D reformations, Jaffe et al. [24] have shown the importance of isotropic data sets from submillimeter detector thickness. Using a 16-MDCT scanner with 0.625-mm detector thickness, the radiation dose was minimally higher compared to both 16- and 8-MDCT scanners with 1.25-mm detector thickness (mean, 21.4, 20.6, and 20.1 mSv, respectively). However, the submillimeter detector thickness was the only one to provide truly isotropic reconstructions with no compromise in spatial resolution. That study also compared reformation thicknesses of 1-5 mm for multiplanar reformations. The results showed that contrast-to-noise ratios increased with increasing reformation thickness, and 2-3 mm thick coronal reformations were qualitatively rated as superior [24].


CT Appearance and Pitfalls
Top
 Abstract
 Introduction
 Incidence
 Pathophysiology
 Clinical Presentation
 Diagnosis
 CT Appearance and Pitfalls
Treatment and Management
 Conclusion
 References
 
With respect to true aneurysms, the CT appearance reflects the pathologic changes in the aneurysm. Splenic artery aneurysms can appear well defined and homogeneous on contrast-enhanced CT (Figs. 2 and 3). Alternatively, mural thrombus may be present (Fig. 5), and peripheral calcification is apparent in many cases (Figs. 4A, 4B and 5).

Three-dimensional rendering improves evaluation of the splenic artery, readily distinguishing tortuous vessel from aneurysm. An additional pitfall on axial images is misinterpreting an aneurysm as a solid pancreatic neoplasm. The literature includes a number of case reports in which aneurysms of mesenteric artery branches have mimicked pancreatic tumors on CT [25-28]. Because islet cell tumors of the pancreas can be markedly hyperattenuating in the arterial or pancreatic phase [29, 30], an unruptured splenic artery aneurysm may mimic one of these hypervascular masses. Using axial images (Figs. 9A, 9B, 9C, 9D and 10A, 10B, 10C, 10D), and even on multiplanar reformations in some cases (Fig. 9A, 9B, 9C, 9D), an aneurysm located in pancreatic tissue can appear as a small, round hyperattenuating mass. Three-dimensional renderings show the relationship of aneurysm to the splenic artery (Figs. 9A, 9B, 9C, 9D and 10A, 10B, 10C, 10D, 10E).


Figure 14
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  		Fig. 9A —70-year-old woman with pancreatic body mass on CT and MRI performed at another institution that was interpreted as probable islet cell neoplasm. Axial contrast-enhanced arterial phase CT scan (A), coronal oblique multiplanar reformation (B), coronal volume rendering (C), and axial color-coded volume rendering from superior orientation (D) show 2-cm aneurysm arising from mid portion of splenic artery and abutting pancreas. Comparison with study from 6 months earlier revealed interval enlargement. Patient was successfully treated with interventional coil embolization of proximal splenic artery and aneurysm.

 

Figure 15
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  		Fig. 9B —70-year-old woman with pancreatic body mass on CT and MRI performed at another institution that was interpreted as probable islet cell neoplasm. Axial contrast-enhanced arterial phase CT scan (A), coronal oblique multiplanar reformation (B), coronal volume rendering (C), and axial color-coded volume rendering from superior orientation (D) show 2-cm aneurysm arising from mid portion of splenic artery and abutting pancreas. Comparison with study from 6 months earlier revealed interval enlargement. Patient was successfully treated with interventional coil embolization of proximal splenic artery and aneurysm.

 

Figure 16
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  		Fig. 9C —70-year-old woman with pancreatic body mass on CT and MRI performed at another institution that was interpreted as probable islet cell neoplasm. Axial contrast-enhanced arterial phase CT scan (A), coronal oblique multiplanar reformation (B), coronal volume rendering (C), and axial color-coded volume rendering from superior orientation (D) show 2-cm aneurysm arising from mid portion of splenic artery and abutting pancreas. Comparison with study from 6 months earlier revealed interval enlargement. Patient was successfully treated with interventional coil embolization of proximal splenic artery and aneurysm.

 

Figure 17
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  		Fig. 9D —70-year-old woman with pancreatic body mass on CT and MRI performed at another institution that was interpreted as probable islet cell neoplasm. Axial contrast-enhanced arterial phase CT scan (A), coronal oblique multiplanar reformation (B), coronal volume rendering (C), and axial color-coded volume rendering from superior orientation (D) show 2-cm aneurysm arising from mid portion of splenic artery and abutting pancreas. Comparison with study from 6 months earlier revealed interval enlargement. Patient was successfully treated with interventional coil embolization of proximal splenic artery and aneurysm.

 

Figure 18
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  		Fig. 10A —52-year-old woman with history of surgically corrected aortic coarctation and 2 months of abdominal pain and weight loss. CT performed at outside institution revealed two enhancing lesions in pancreas that were interpreted as neuroendocrine tumors. (Reprinted with permission from Horton KM, Hruban RH, Yeo C, Fishman EK. Multi-detector row CT of pancreatic islet cell tumors. RadioGraphics 2006; 26:453-464 [30]). Repeat contrast-enhanced arterial phase MDCT with axial images (A and B), axial oblique maximum intensity projection from superior orientation (C), and coronal color-coded volume renderings (D and E) reveal that lesion is actually partially calcified aneurysm arising from splenic artery and located in body of pancreas.

 

Figure 19
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  		Fig. 10B —52-year-old woman with history of surgically corrected aortic coarctation and 2 months of abdominal pain and weight loss. CT performed at outside institution revealed two enhancing lesions in pancreas that were interpreted as neuroendocrine tumors. (Reprinted with permission from Horton KM, Hruban RH, Yeo C, Fishman EK. Multi-detector row CT of pancreatic islet cell tumors. RadioGraphics 2006; 26:453-464 [30]). Repeat contrast-enhanced arterial phase MDCT with axial images (A and B), axial oblique maximum intensity projection from superior orientation (C), and coronal color-coded volume renderings (D and E) reveal that lesion is actually partially calcified aneurysm arising from splenic artery and located in body of pancreas.

 

Figure 20
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  		Fig. 10C —52-year-old woman with history of surgically corrected aortic coarctation and 2 months of abdominal pain and weight loss. CT performed at outside institution revealed two enhancing lesions in pancreas that were interpreted as neuroendocrine tumors. (Reprinted with permission from Horton KM, Hruban RH, Yeo C, Fishman EK. Multi-detector row CT of pancreatic islet cell tumors. RadioGraphics 2006; 26:453-464 [30]). Repeat contrast-enhanced arterial phase MDCT with axial images (A and B), axial oblique maximum intensity projection from superior orientation (C), and coronal color-coded volume renderings (D and E) reveal that lesion is actually partially calcified aneurysm arising from splenic artery and located in body of pancreas.

 

Figure 21
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  		Fig. 10D —52-year-old woman with history of surgically corrected aortic coarctation and 2 months of abdominal pain and weight loss. CT performed at outside institution revealed two enhancing lesions in pancreas that were interpreted as neuroendocrine tumors. (Reprinted with permission from Horton KM, Hruban RH, Yeo C, Fishman EK. Multi-detector row CT of pancreatic islet cell tumors. RadioGraphics 2006; 26:453-464 [30]). Repeat contrast-enhanced arterial phase MDCT with axial images (A and B), axial oblique maximum intensity projection from superior orientation (C), and coronal color-coded volume renderings (D and E) reveal that lesion is actually partially calcified aneurysm arising from splenic artery and located in body of pancreas.

 

Figure 22
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  		Fig. 10E —52-year-old woman with history of surgically corrected aortic coarctation and 2 months of abdominal pain and weight loss. CT performed at outside institution revealed two enhancing lesions in pancreas that were interpreted as neuroendocrine tumors. (Reprinted with permission from Horton KM, Hruban RH, Yeo C, Fishman EK. Multi-detector row CT of pancreatic islet cell tumors. RadioGraphics 2006; 26:453-464 [30]). Repeat contrast-enhanced arterial phase MDCT with axial images (A and B), axial oblique maximum intensity projection from superior orientation (C), and coronal color-coded volume renderings (D and E) reveal that lesion is actually partially calcified aneurysm arising from splenic artery and located in body of pancreas.

 
The CT appearance of peripancreatic pseudoaneurysms arising from various mesenteric artery branches has been described in small case series [31, 32]. On CT, splenic artery pseudoaneuryms have been identified in pseudocysts, appearing as focal regions of enhancement in the low-density intracystic fluid [31]. Peripancreatic pseudoaneurysms may show increased attenuation on unenhanced scans, and the perfused portion will enhance strongly after contrast infusion [32]. This enhancing component may be surrounded by thrombus (Fig. 6A, 6B) or hematoma (Fig. 8A, 8B).


Treatment and Management
Top
 Abstract
 Introduction
 Incidence
 Pathophysiology
 Clinical Presentation
 Diagnosis
 CT Appearance and Pitfalls
 Treatment and Management
Conclusion
 References
 
Aneurysms and pseudoaneurysms of the splenic artery require different management strategies [33]. Most data suggest that treatment of symptomatic splenic artery aneurysms should be performed [8]. In addition, several high-risk groups should also be considered for repair, even in the asymptomatic patient. In particular, pregnant women or women of childbearing age should be considered for repair, as should patients with a liver transplant or patients with cirrhosis and portal hypertension. However, no consensus has been reached regarding intervention in asymptomatic patients with splenic artery aneurysm. The smallest ruptured aneurysm over a 4-year experience at the Mayo Clinic was 2 cm [8]. Recommendations are to treat asymptomatic aneurysms greater than 2 cm in patients with reasonable operative risk and life expectancy greater than 2 years [1, 8].

The appropriate treatment for splenic artery aneurysms depends on the location of the lesion, the age of the patient, operative risks, and clinical status. A greater than 0.5% operative mortality rate is associated with elective repair, so it is imperative that patients be selected carefully [17]. Aneurysms located in the proximal or middle third of the splenic artery may be treated with simple excision, with proximal and distal ligation of the artery and splenic preservation (through the short gastric vessels). For aneurysms located in the distal third, resection with splenectomy is most often performed [33].

Recently, transcatheter embolization has been gaining favor [34]. Although success rates of approximately 85% are lower than those of direct surgical intervention, associated operative morbidity and mortality rates are significantly reduced [11].

Because of the high risk of rupture and the high mortality rate if splenic artery pseudoaneurysm ruptures, the earliest possible intervention is deemed necessary. As with symptomatic splenic artery aneurysms, splenectomy with or without partial pancreatectomy has been the treatment of choice [35]. Surgical intervention carries mortality and morbidity risks of 1.3% and 9%, respectively [35]. More recently, transabdominal and endovascular techniques have reported variable success rates [12, 35]. Endovascular techniques using coils, detachable balloons, inert particles, or Gelfoam (gelatin sponge, Upjohn) have reported success rates of 75-85% [35]. Case reports describe the use of percutaneous thrombin injection under CT guidance to treat splenic artery pseudoaneurysms in patients who were not candidates for endovascular therapy [12, 36]. In one case, partial recanalization was identified on a 1-month follow-up CT, necessitating reinjection [12]. Rare cases of recanalization have been reported after endovascular embolization, so CT at 1 and 6 months after endovascular intervention has been advised [35].


Conclusion
Top
 Abstract
 Introduction
 Incidence
 Pathophysiology
 Clinical Presentation
 Diagnosis
 CT Appearance and Pitfalls
 Treatment and Management
 Conclusion
References
 
The exceptional resolution of 3D renderings from MDCT data sets will result in identification of aneurysms and pseudoaneurysms that would have eluded detection on older generation scanners. Three-dimensional renderings are valuable for distinction from tortuous vessel or small, hyperattenuating islet cell tumor of the pancreas. Clinical history can aid in distinguishing true aneurysms from pseudoaneurysms; however, associated radiologic findings may be identified to suggest pertinent coexisting disease. Specifically, concomitant pancreatitis or peptic ulcer disease is a known causes of pseudoaneurysms. Signs of cirrhosis, portal hypertension, or arteritis may be present in the setting of true aneurysms. Once aneurysms or pseudoaneurysms are detected, radiologists should promptly communicate the size, exact location (proximal, mid, or distal splenic artery), and any indicators of rupture because these factors affect management decisions.


References
Top
 Abstract
 Introduction
 Incidence
 Pathophysiology
 Clinical Presentation
 Diagnosis
 CT Appearance and Pitfalls
 Treatment and Management
 Conclusion
 References
 

  1. Trastek VF, Pairolero PC, Joyce JW, Hollier LH, Bernatz PE. Splenic artery aneurysms. Surgery 1982;91 : 694-699[Medline]
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  3. Bedford PD, Lodge B. Aneurysm of the splenic artery. Gut 1960; 1:312 -320[Abstract/Free Full Text]
  4. Rokke O, Sondenaa K, Amundsen S, Bjerke-Larssen T, Jensen D. The diagnosis and management of splanchnic artery aneurysms. Scand J Gastroenterol 1996; 31:737 -743[Medline]
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  6. Beaussier M. Sur un aneurisme de l'artère splénique dont les parois se sont ossifies. J Med Clin Pharm1770; 32:157
  7. Moore SW, Guida PM, Schumacher HW. Splenic artery aneurysm. Bull Soc Int Chir 1970;29 : 210-218[Medline]
  8. Abbas MA, Stone WM, Fowl RJ, et al. Splenic artery aneurysms: two decades experience at Mayo clinic. Ann Vasc Surg2002; 16:442 -449[CrossRef][Medline]
  9. Lee PC, Rhee RY, Gordon RY, Fung JJ, Webster MW. Management of splenic artery aneurysms: the significance of portal and essential hypertension. J Am Coll Surg 1999;189 : 483-490[CrossRef][Medline]
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