Portal aneurysm

Contraindications include coagulation disorders, superficial hyperechoic foci (e. g. haemangioma), vascular aneurysm, portal hypertension, obstructive jaundice and hydatid cysts. Care should also be taken not to damage any unknown structures along the path of the biopsy needle. 

Percutaneous splenoportography has lost its importance. Should a direct procedure be indicated, laparoscopic splenoportography is a possible alternative. Recently, a new technique has been described. (134) The percutaneous splenic puncture is performed using a thin needle under screen control, with the needle directed at the splenic hilus. The pressure of the splenic pulp can be measured directly in order to estimate the portal vein pressure. Contrast medium is injected manually or by a special device. From this depot in the red pulp, the splenic vein, the portal vein and the intrahepatic branches of the portal vein are contrasted within a few seconds, (s. fig. 8.12) Complications resulting from percutaneous splenoportography include afterbleeding from the spleen, bilateral rupture of the spleen, arterial aneurysms and a.v. shunts — these complications are serious in nature, but rare. Contraindications for the procedure should be carefully observed, (s. tab. 8.6)... 

After perforation (60-80% of patients), an aneurysm becomes manifest in the form of abdominal pain, which can be very severe. (129) When an intrahepatic haema-toma reaches the bile ducts, haemobilia may result (about 40% of cases) (133), just as compression of the excretory bile ducts may lead to the development of jaundice (in some 50% of cases). (134,138) Heavy bleeding into the free abdominal cavity constitutes an acute abdomen with signs of circulatory shock. Bleeding into the intestinal tract or into the portal vein is less frequent. Lethality due to rupture is 30-50% the prognosis for massive bleeding with haemoperitoneum is even poorer. 

With unclarified abdominal pain, sonography is usually the diagnostic procedure of choice. An aneurysm appears as a round or oval focus either intrahepatically or extrahepatically between the portal hilum and the pancreas. The hypoechoic, cystic focus may contain hyperechoic, thrombotic material. Occasionally, there is a connection to an afferent vessel. (128) A suspected aneurysm can be confirmed by colour Doppler sonography, with the possibility of distinguishing blood flow and arterial blood. An echo-free aneurysm provides a typical arterial sphygmogram. 

Ascenti, G., Zimbaro, G., Mazziotti, S., Visalli, C., Lamberto, S., Scri-bano, E., Gaeta, M. Intrahepatic portal vein aneurysm three-dimensional power Doppler demonstration in four cases. Abdom. Imag. 2001 26 520-523... 

Erdem, C.Z., Erdem, L.O., Comert, M., Ustnndag, Y., Gundogu, S. Multiple intra-hepatic portal vein aneurysms — findings on magnetic resonance angiography. Clin. Radiol. 2003 58 899—901... 

Okur, N., Inal, M., AkgnI, E., Demircan, O. Spontaneous rupture and thrombosis of an intrahepatic portal vein aneurysm. Abdom. Imag. 2003 28 675 -677... 

The majority of patients who develop significant bleeding as a complication of pancreatitis do so because of associated upper gastrointestinal ulceration and inflammation. Occasionally portal vein thrombosis can lead to variceal bleeding [4], Neither of these pathologies is within the remit of this chapter. The estimated incidence of visceral aneurysm development in patients with pancreati-... 

Fig.7.9a,b. A 52-year-old woman with a recent history of gall stone pancreatitis was admitted with further abdominal pain. A CECT scan suggested an aneurysm of uncertain origin. Angiography revealed a true (Type la) aneurysm of an aberrant right hepatic artery (a). CECT had revealed a patent portal vein and so proximal and distal coil embolization was performed (b). There were no further complications and the patient is alive and well at 36 months... 

There is one further indication for thrombin occlusion of pancreatitis associated visceral aneurysms. Where the portal vein has occluded as a complication and the patient has a proximal splenic or gastroduodenal aneurysm, the proximal and distal coil embolization of which could compromise the hepatic arterial supply to the liver causing liver infarction, thrombin injection maybe a safer technique [29]. 

Although atherosclerosis has been implicated, there is debate as to whether it is the cause or the result of aneurysm formation. The heavy calcification seen in splenic artery aneurysms maybe due to altered hemodynamics. For example, splenic artery aneurysms can be seen with portal hypertension (Fig. 8.3). Saccular or berry aneurysms associated with hypertension and atherosclerosis arise at... 

Fig. 8.3. a Celiac angiogram in a patient with portal hypertension demonstrating a distal splenic artery aneurysm, b Celiac angiogram from another patient with multiple splenic aneurysms associated with portal hypertension who has undergone liver transplantation. Note the large hepatic pseudoaneurysm just medial to the upper pole of the right kidney, c Selective common hepatic artery injection in the patient from b... 

Intrahepatic rupture can result in hemobilia with or without biliary obstruction. These patients can present with right upper quadrant pain, jaundice, fever, melena, or hematemesis. Extrahepatic rupture usually presents acutely and can lead to exsanguination due to massive intraperitoneal hemorrhage. They can erode into adjacent structures such as the stomach, common bile duct, duodenum, or portal vein. Due to the high mortality from rupture, elective treatment of small asymptomatic aneurysms has been advocated. 

Considered the most common, the splenic artery aneurysm has been reported to comprise approximately 60% of all VAAs [1,2]. This entity affects females four times as often as males. Typically seen in multiparous women, this aneurysm has a high propensity to rupture in the third trimester of pregnancy [29]. Asymptomatic aneurysms can often be seen as round calcified masses in the left upper quadrant on plain films and computed tomography. This type of aneurysm has been associated with portal hypertension. Many causes exist and include pancreatitis, portal hypertension, endocarditis, cystic medial necrosis, iatrogenic, and collagen vascular diseases such as Ehlers-Danlos. 

Barrett JM, Caldwell BH (1981) Association of portal hypertension and ruptured splenic artery aneurysm in pregnancy. Obstet Gynecol 57 255-257... 

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