To investigate contrast-enhanced ultrasound (CEUS) findings in portal venous system aneurysms (PVSAs).

In this multi-center, retrospective, case series study, we evaluated CEUS features of seven cases of PVSAs that were found incidentally on conventional ultrasound in the period 2007-2013. Three Ultrasound Centers were involved (Chieti, Italy, Bad Mergentheim, Germany, and Cluj-Napoca, Romania). All patients underwent CEUS with Sonovue(®) (Bracco, Milan, Italy) at a standard dose of 2.4 mL, followed by 10 mL of 0.9% saline solution. The examinations were performed using multifrequency transducers and low mechanical index. We considered aneurysmal a focal dilatation of the portal venous system with a size that was significantly greater than the remaining segments of the same vein, and that was equal or larger than 21 mm for the extrahepatic segments of portal venous system, main portal vein and bifurcation, and 9 mm for the intrahepatic branches.

After contrast agent injection, all PVSAs were not enhanced in the arterial phase (starting 8-22 s). All PVSAs were then rapidly enhanced in the early portal venous phase (starting three to five seconds after the arterial phase, 11-30 s), with persistence and slow washout of the contrast agent in the late phase (starting 120 s). In all patients, CEUS confirmed the presence of a "to-and-fro" flow by showing a swirling pattern within the dilatation in the early portal venous phase. CEUS also improved the delineation of the lumen, and was reliable in showing its patency degree and integrity of walls. In one patient, CEUS showed a partial enhancement of the lumen with a uniformly nonenhancing area in the portal venous and late phases, suggesting thrombosis.

In our case series, we found that CEUS could be useful in the assessment and follow-up of a PVSA. Further studies are needed to validate its diagnostic accuracy.

Extrahepatic Portal vein aneurysm (EPVA) is a rare finding that may be associated with different complications, e.g. thrombosis, rupture, portal hypertension and compression of adjacent structures. It is being diagnosed more frequently with the advent of modern cross-sectional imaging. Our review of the English literature disclosed 13 cases of thrombosed EPVA.

A 50-years-old woman presented with acute abdominal pain but no other symptom. She had no relevant medical history. Palpation of the right upper quadrant showed tenderness. Laboratory tests were unremarkable. A computed tomography showed portal vein aneurysm measuring 88 × 65 mm with thrombosis extending to the superior mesenteric and splenic vein. The patient was treated conservatively with anticoagulation therapy. She was released after two weeks and followed on an outpatient basis. At two months, she reported decreased abdominal pain and her physical examination was normal. A computed tomography was performed showing a decreased thrombosis size and extent, measuring 80 × 55 mm.

Although rare, surgeons should be made aware of this entity. Complications are various. Conservative therapy should be chosen in first intent in most cases. We reported the case of the second largest thrombosed extra-hepatic PVA described in the literature, treated by anticoagulation therapy with a good clinical and radiological response.

Portal vein aneurysms are very rare and represent <3% of all venous aneurysms. They can be congenital or acquired. Most patients do not have liver disease at diagnosis. Although uncommon, portal vein aneurysm has been described after liver transplant. We report the case of a six-yr-old girl who presented with an aneurysm of the extrahepatic portal vein after segmental liver transplantation. Because the patient was asymptomatic and owing to its extrahepatic location, this aneurysm has been successfully followed by clinical exam and imaging for four yr.

We report a case of extrahepatic portal vein aneurysm (PVA) in the late postoperative period after orthotopic liver transplantation (OLT). A 46-year-old man underwent OLT in 2001 for treatment of hepatitis B virus-induced cirrhosis and received ultrasound follow-up for 9 years. The long-term ultrasound observations showed that the diameter of the main portal vein had progressively increased from 12 mm in 2001 to 34 mm in 2007, and then remained at 34 mm from 2007 to 2010. The patient did not show any symptoms or complications that required surgical treatment during the clinical follow-up. Our case suggests that PVA after OLT can remain without a sign of deterioration for a long time, and careful observation by ultrasound may be one of the options in the clinical management.

Relatively few pediatric donors are available in relation to the number of children waiting for a liver transplant. This limited number of pediatric donor livers leads to the use of adult livers, usually requiring more complex portal vein (PV) anastomoses. These anastomoses are complicated by differences in PV caliber between donors and recipients, as well as by limitations of PV length, which may be inadequate to reach the recipient spleno-mesenteric junction. Three types of post-transplant complications result from these complexities: 1) anomalies of the portal flow; 2) stenosis of the PV anastomosis; and 3) PV thrombosis. Abnormal portal flow may rarely need a specific intervention, but persistent stenosis or appearance of signs of portal hypertension need to be corrected. Balloon dilatation and placement of a stent are usually successful to repair stenosis. Portal vein thromboses are in general diagnosed in the immediate post-operative period and frequently lead to re-transplantation; however, thrombolytic therapy should be attempted in children without major signs of liver necrosis. When intra-hepatic portal vein(s) are permeable, despite extrahepatic PV thrombosis, a Meso-Rex shunt may be the indicated therapy.

Portal venous aneurysms are a rare finding. The reported incidence is on the rise with increasing use of modern imaging techniques in clinical practice. However, there is still much to be elicited regarding their aetiology, natural history, and management.

An 80-year-old woman presented with abdominal pain and nausea. Investigations showed a hypoechoic area in the region of the head of pancreas on ultrasound, which was found to be a portal venous aneurysm on CT. In view of her multiple comorbidities, a conservative approach was taken.

Portal venous aneurysms represent approximately 3% of all venous aneurysms with a reported prevalence of 0.43%. They may be congenital, due to failure of complete regression of the right vitelline vein, or acquired secondary to portal hypertension. The primary presentation of portal vein aneurysm is abdominal pain, followed by incidental detection on imaging, with a minority of patients presenting with gastrointestinal bleeding. Complications of PVA include thrombosis, biliary tract obstruction, inferior vena cava obstruction, and duodenal compression. On the whole PVAs are stable and have a low risk of complications with 88% of patients showing no progression of aneurysm size or complications on subsequent follow up scans.

We recommend that portal venous aneurysms be assessed using colour Doppler ultrasonography in the first instance with CT scans reserved for indeterminate cases or symptomatic patients. Due to the slow progression of such aneurysms, surgery is recommended only for symptomatic patients or those with complications secondary to portal venous aneurysms.