120,396 Registered Members as of 09/02/2014.
Vascular/Cardiac » Visceral vascular
Splenic artery aneurysm and splenic hilar varices
« Back to Listing
 
Author(s) :
Chaitali Shah, FRCR
 
Presentation A 50 year old cirrhotic patient presents with pain in the left upper quadrant. An ultrasound was performed.
 
 
 
Caption: Sagittal view of the spleen
Description: A rounded hypoechoic structure is seen in the para-hilar region. Multiple tubular hypoechoic channels are seen in the splenic hilar region. The spleen appears mildly enlarged- was 14.0 cm.
 
 
 
Caption: Sagittal scan of the spleen
Description: This view of the spleen at a slightly different plane also demonstrates multiple serpigineous tubular channels in the hilar region. The visualized splenic parenchyma appears normal.
 
 
 
Caption: Transverse scan of the spleen
Description: This view of the spleen demonstrates the rounded hypoechoic structure again in close proximity to the splenic hilum.
 
 
 
Caption: Transverse color Doppler scan of the spleen
Description: The striking feature of this color Doppler image is the color seen in the rounded hypoechoic structure. It demonstrates the classic yin-yang pattern seen in aneurysm.
 
 
 
Caption: Sagittal color Doppler view of the spleen
Description: The multiple tubular channels seen in the splenic hilum fill with color and represent splenic hilar varices in a patient with liver cirrhosis.
 
Differential Diagnosis Splenic artery aneurysm and splenic hilar varices
 
Final Diagnosis Incidental finding of splenic artery aneurysm and splenic hilar varices in a patient with cirrhosis
 
Discussion

Splenic artery aneurysms are rare entities and can be catastrophic causing fatal exsanguinating hemorrhage if they rupture. However, improved imaging techniques and minimally invasive treatment options have improved the prognosis of this condition.

The causative factors for an aneurysm of the splenic artery are not very well known and many different theories have been postulated. According to one author, degeneration of the media, weakening of the vessel wall due to atherosclerotic changes and high blood flow states such as pregnancy and chronic portal hypertension, which result in increased splenic blood flow volume, are all implicated in the pathogenesis of the aneurysm. Of all these factors, hypertensive states [both essential and portal hypertension] resulting in hyperkinetic flow states seems to be an established risk factor in developing splenic artery aneurysms. Pregnancy is associated with increased risk of rupture of the aneurysm. A pseudoaneurysm may be secondary to trauma, infection or pancreatitis.

Gray scale and color Doppler sonography play a key role in the diagnosis of splenic artery aneurysm, since many of these aneurysms are either detected as incidental findings or they present with rupture and as acute abdomen.
Ultrasound features:
1. The aneurysm is seen as a rounded cystic appearing structure in very close proximity to the splenic artery.
2. It may be intra- or extra-splenic in location and can be single or multiple.
3. The wall of the aneurysm may show calcifications. If it is heavily calcified, the aneurysm may be obscured on gray scale ultrasound.
4. Color and power Doppler demonstrate the turbulent flow in the aneurysm, often appearing as the classic yin-yang pattern within the aneursymal cavity.
5. Spectral waveform analysis shows an arterial waveform with elevated flow velocities.
6. Amany of these patients have associated portal hypertension as the causative factor, splenomegaly and splenic hilar varices may also be seen. The splenic varices represent porto-systemic communications that occur as a compensatory mechanism secondary to elevated pressures in the portal venous system. These veins in the splenic hilar region represent collaterals between the splenic, coronary or short gastric veins and the left renal or adrenal vein.

A conservative approach in cases of small aneurysms, aneurysmectomy [open or laparoscopic], splenic artery ligation and coil embolization are some of the treatment options available. For the treatment of symptomatic varices, sclerotherapy or surgical ligation is the treatment.

 
Case References 1. D`ambrosio et al. Intraperitoneal hemorrhage from rupture of an aneurysm of splenic artery: case report and literature review. Ann Ital Chir. 2003 Jan-Feb; 74(1):97-101.
2. Dave SP, et al. Splenic artery aneurysm in the 1990s. Ann Vasc Surg. 2000 May; 14(3):223-9.
3. Lee P:C, et al. Management of splenic artery aneurysms: the significance of portal and essential hypertension. J Am Coll Surg. 1999 Nov; 189(5):483-90.
4. Ishida H, et al. Splenic artery aneurysm. Abdom Imaging. 1998 Nov-Dec; 23(6):627-32.
5. Nishida O, et al. Hemodynamics of splenic artery aneurysm. Gastroenterology. 1986 Apr; 90(4):1042-6.
6. Ohta M, et al. Splenic hyperkinetic state and splenic artery aneurysm in portal hypertension. Hepatogastroenterology. 1992 Dec;39(6):529-32.
7. Ueda J, et al. Portal hypertension with intra- and extrasplenic arterial aneurysms and large venous varices. Cardiovasc Intervent Radiol. 1995 Jul-Aug; 18(4):243-6
 
Other contents by this Author