Advantages of the meso-Rex bypass compared with portosystemic shunts in the management of extrahepatic portal vein obstruction in children. J Am Coll Surg. 2013;216:83-89. [PMID: 23177370 DOI: 10.1016/j.jamcollsurg.2012.09.013]

Extrahepatic Portal Venous Obstruction: What Should be the Mainstay of Treatment?

The two cornerstones of management for Extrahepatic portal vein obstruction (EHPVO) are endotherapy and surgery [Porto-systemic shunts (PSS)/Mesorex bypass (MRB)]. Endotherapy is the mainstay of treatment for acute variceal bleed control and has also been used extensively for secondary prophylaxis till variceal eradication is achieved. However, long-term follow-up beyond endoscopic eradication of esophageal varices (EEEV) indicates that there are numerous delayed bleed and non bleed sequelae of EHPVO, which merit surgery as a definitive procedure to decompress the hypertensive portal venous system. While endotherapy obliterates natural porto-systemic collaterals in the gastroesophageal region, persistently raised portal pressures manifest as an increase in secondary isolated gastric varices, ectopic varices, portal hypertensive vasculopathy, issues related to massive splenomegaly, portal biliopathy, growth retardation and hence impaired quality of life (QOL). An ideal management strategy should address both bleed and non-bleed consequences of EHPVO and translate into a near normal QOL. Further, MRB has opened up new dimensions to the management philosophy of EHPVO. This review article critically evaluates the role of surgery and endotherapy based on available literature and authors' own experience.Surgery and endotherapy are complementary. However, with increasing duration of follow-up post EEEV, it is evident that there is resurgence in the role of surgery (PSS/MRB) as a single one time definitive procedure for alleviating all bleed and delayed non bleed sequelae of EHPVO.Surgery for EHPVO (PSS/MRB) should not be allowed to become a dying art and future generations of surgeons should continue to receive training in this specialized area of surgery.

Combined Rex-bypass shunt with pericardial devascularization alleviated prehepatic portal hypertension caused by cavernomatous transformation of portal vein

OBJECTIVE

To evaluate the effects of combined Rex-bypass shunt and pericardial devascularization on prehepatic portal hypertension secondary to cavernomatous transformation of portal vein (CTPV).

METHODS

Forty-two patients aged from 3 years to 49 years (divided into 3 groups), 26 cases male and 16 female, with prehepatic vascular hepertention were treated with Rex-bypass shunt combined with pericardial devascularization. In each patient, preoperative assessment included ultrasound and computed tomographic angiography of the portal vein and blood analysis. The procedure was Rex-bypass shunt (with or without graft), and patients with moderate or severe gastroesophageal varices required additional paraesophagogastric devascularization. Splenectomy or subtotal splenectomy was performed if combined hypersplenism co-existed. All data were analyzed retrospectively.

RESULTS

No intraoperative death occurred, blood routine analysis improved (P < 0.05), the blood flow velocity (P < 0.05) and diameter (P < 0.05) of the left portal vein (LPV) significantly increased, the esophageal and gastric varices significantly relieved in 34 patients (P < 0.05), and better effects of earlier operations were demonstrated than the delayed ones (P < 0.05). During the period of follow-up from 6 to 64 months, the overall patency rate was 85.7% and the younger the age the better of the effect.

CONCLUSION

Rex-bypass shunt combined with pericardial devascularization is a safe and effective procedure for prehepatic portal hypertension caused by CTPV.

Evaluation of Rex Shunt on Cavernous Transformation of the Portal Vein in Children

BACKGROUND

Children with cavernous transformation of the portal vein (CTPV) develop severe complications from prehepatic portal hypertension, such as recurrent variceal bleeding and thrombocytopenia. In this study, we reported the results of 30 children with symptomatic CTPV that were treated by a Rex shunt. The effectiveness of this surgical approach was evaluated.

METHODS

A retrospective review was performed of 30 children aged between 3 and 18 years with CTPV, who underwent a Rex shunt between 2008 and 2015. All children were evaluated based on symptoms, complete blood count, portal system color-flow Doppler ultrasound or computed tomography angiography portography and gastroscopy for gastroesophageal varices pre- and postoperatively. Children were also evaluated during follow-up. Intraoperative evaluations included liver biopsy, portography and portal pressure.

RESULTS

Twenty-one patients demonstrated intermittent bleeding from gastroesophageal varices, 3 patients showed hypersplenism with varying degrees of leucopenia, anemia and thrombocytopenia, and in 6 patients both bleeding and hypersplenism were observed. Rex was successful in 28 patients (93.3%). The portal pressure immediately decreased significantly after placing of the shunt (P < 0.01). During the clinical follow-up period within 2-82 months, transaminase levels were maintained in the normal range. Blood flow velocity and diameter of the left portal vein significantly increased after surgery (P < 0.01). In addition, leukocyte and platelet counts increased postoperatively and anemia improved significantly (P < 0.01). Gastroscopy results indicated that the degree of gastroesophageal varices significantly alleviated postoperatively within 3 months and 1 year (P < 0.01). In 2 patients who demonstrated nodular cirrhosis and chronic active hepatitis, success of the Rex shunt was not achieved after operation. We found that for Rex effectiveness hepatic pathology and patient age were major determinants.

CONCLUSION

Rex shunt is an effective approach for the treatment of children suffering from CTPV at an early stage that do not show additional liver lesions.

Diagnosis and treatment guidelines for aberrant portal hemodynamics: The Aberrant Portal Hemodynamics Study Group supported by the Ministry of Health, Labor and Welfare of Japan

Idiopathic portal hypertension (IPH), causing aberrant portal hemodynamics, is a disease with an as yet unidentified cause and no established treatment protocol. The Japanese research group on IPH in Japan was set up in 1975 by the Ministry of Health, Labor and Welfare. Extrahepatic portal obstruction and Budd-Chiari syndrome (BCS) have since been added to the group's research subjects. The aims of the research group are to accurately evaluate the current status of the three diseases in Japan, elucidate their etiology and pathogenesis, and develop new treatments. Due to the long-term efforts of the Japanese research group, aberrant portal hemodynamics has been investigated in a variety of aspects, from epidemiological and pathological studies to molecular biology analyses. As a result, it has been shown that there are abnormal genes in the liver, specific for IPH. In addition, pathological findings of BCS were internationally compared and the difference in findings between Japan and Europe (or North America) has been clarified. Furthermore, it was found that complication rates of hepatocellular carcinoma in BCS were higher in Japan. Based on the research, "Diagnosis and treatment of aberrant portal hemodynamics (2001)", including diagnostic criteria for aberrant portal hemodynamics, was published in 2001. In 2013, it was revised to "Diagnosis and treatment guidelines for aberrant portal hemodynamics (2013)" after the incorporation of diagnosis and treatment in accordance with its current status.

Portal Vein Thrombosis: Recent Advance

Portal vein thrombosis is a life-threatening vascular disorder of the liver. In this chapter, I will review the recent advance regarding the epidemiology, etiology, management, and prognosis of portal vein thrombosis.

Primary prophylaxis of variceal bleeding in children and the role of MesoRex Bypass: Summary of the Baveno VI Pediatric Satellite Symposium

Approaches to the management of portal hypertension and variceal hemorrhage in pediatrics remain controversial, in large part because they are not well informed by rigorous clinical studies. Fundamental biological and clinical differences preclude automatic application of approaches used for adults to children. On April 11-12, 2015, experts in the field convened at the first Baveno Pediatric Satellite Meeting to discuss and explore current available evidence regarding indications for MesoRex bypass (MRB) in extrahepatic portal vein obstruction and the role of primary prophylaxis of variceal hemorrhage in children. Consensus was reached regarding MRB. The vast majority of children with extrahepatic portal vein obstruction will experience complications that can be prevented by successful MRB surgery. Therefore, children with extrahepatic portal vein obstruction should be offered MRB for primary and secondary prophylaxis of variceal bleeding and other complications, if appropriate surgical expertise is available, if preoperative and intraoperative evaluation demonstrates favorable anatomy, and if appropriate multidisciplinary care is available for postoperative evaluation and management of shunt thrombosis or stenosis. In contrast, consensus was not achieved regarding primary prophylaxis of varices. Although variceal hemorrhage is a concerning complication of portal hypertension in children, the first bleed appears to be only rarely fatal and the associated morbidity has not been well characterized.

CONCLUSION

There are few pediatric data to indicate the efficacy and safety of pharmacologic or endoscopic therapies as primary prophylaxis or that prevention of a sentinel variceal bleed will ultimately improve survival; therefore, no recommendation for primary prophylaxis with endoscopic variceal ligation, sclerotherapy, or nonspecific beta-blockade in children was proposed.

Epiploic gonadal vein as a new bypass route for extrahepatic portal venous obstruction: report of a case

A 61-year-old man was referred to our hospital to treat extrahepatic portal venous obstruction. Endoscopic injection sclerotherapy (EIS) was performed for the esophageal varices; however, the patient returned with massive hematemesis from gastric varices 6 months after treatment. Although the varices were treated with EIS, gastric devascularization and splenectomy concomitant with shunt surgery were required to treat uncontrollable, frequent diarrhea and abdominal distension. Because the splenic vein, left gastric vein, left portal vein, and inferior vena cava were inadequate for anastomosis, an epiploic gonadal vein bypass was performed. The bypass graft remains patent 7 months after surgery, and the patient is in good health without any clinical symptoms. We describe a new bypass route for extrahepatic portal venous obstruction.

Transjugular Intrahepatic Portosystemic Shunt for Extrahepatic Portal Venous Obstruction in Children

OBJECTIVES

To evaluate the feasibility and efficacy of transjugular intrahepatic portosystemic shunt (TIPS) for extrahepatic portal venous obstruction with recurrent variceal bleeding in children.

METHODS

From November 2005 to December 2013, 28 consecutive paediatric patients with extrahepatic portal venous obstruction treated with TIPS for recurrent variceal bleeding refractory to medical/endoscopic therapy and/or surgical treatment in a tertiary-care centre were followed until last clinical evaluation or death. The median follow-up time was 36.0 months (range 4.0-106.0 months).

RESULTS

Seventeen boys and 11 girls of ages 7.1 to 17.9 years (median 12.3 years) weighing 19.0 to 62.0 kg (median 33.5 kg) were treated. TIPS was successfully placed in 17 of 28 (60.7%) patients via a transjugular approach alone (n = 4), a combined transjugular/transhepatic approach (n = 9), or a combined transjugular/transsplenic approach (n = 4). Shunt dysfunction occurred in 6 of 17 (35.3%) patients. The cumulative 1- and 3-year free-from-variceal-rebleeding rates in TIPS success group were higher than those in TIPS failure group (75.0% and 67.5% vs 45.5% and 18.2%, respectively, P = 0.0075). Compared with the TIPS failure group, the improvements in the height-for-age z scores were greater in the TIPS success group (P = 0.017). Procedure-related complication occurred in 1 patient (3.6%), and no episode of post-TIPS hepatic encephalopathy occurred in any patient. Except 1 patient in the TIPS success group died at 115 postoperative days, all patients were alive.

CONCLUSIONS

TIPS is feasible and effective in children with extrahepatic portal venous obstruction and recurrent variceal bleeding. TIPS could represent a less-invasive alternative to traditional surgical portosystemic shunting or a valuable treatment option if surgery and endoscopic treatment failed.

Surviving Sengstaken

AIM OF THE STUDY

To report the outcomes of children who underwent Sengstaken-Blakemore tube (SBT) insertion for life-threatening haemetemesis.

METHODS

Single institution retrospective review (1997-2012) of children managed with SBT insertion. Patient demographics, diagnosis and outcomes were noted. Data are expressed as median (range).

MAIN RESULTS

19 children [10 male, age 1 (0.4-16) yr] were identified; 18 had gastro-oesophageal varices and 1 aorto-oesophageal fistula. Varices were secondary to: biliary atresia (n=8), portal vein thrombosis (n=5), alpha-1-anti-trypsin deficiency (n=1), cystic fibrosis (n=1), intrahepatic cholestasis (n=1), sclerosing cholangitis (n=1) and nodular hyperplasia with arterio-portal shunt (n=1). Three children deteriorated rapidly and did not survive to have post-SBT endoscopy. The child with an aortooesophageal fistula underwent aortic stent insertion and subsequently oesophageal replacement. Complications included gastric mucosal ulceration (n=3, 16%), pressure necrosis at lips and cheeks (n=6, 31%) and SBT dislodgment (n=1, 6%). Six (31%) children died. The remaining 13 have been followed up for 62 (2-165) months; five required liver transplantation, two underwent a mesocaval shunt procedure and 6 have completed endoscopic variceal obliteration and are under surveillance.

CONCLUSIONS

SBT can be an effective, albeit temporary, life-saving manoeuvre in children with catastrophic haematemesis.

Assessment of surgical portosystemic shunts and associated complications: The diagnostic and therapeutic role of radiologists

Surgical portosystemic shunting, the formation of a vascular connection between the portal and systemic venous circulation, has been used as a treatment to reduce portal venous pressure. Although the use of portosystemic shunt surgery in the management of portal hypertension has declined during the past decade in favour of alternative therapies, and subsequently surgeons and radiologists became less familiar with the procedure, it remains a well-established treatment. Knowledge of different types of surgical portosystemic shunts, their pathophysiology and complications will help radiologists improve communication with surgeons and enhance their understanding of the diagnostic and therapeutic role of radiology in the assessment and management of these shunts. Optimal assessment of the shunt is essential to determine its patency and allow timely intervention. Both non-invasive and invasive imaging modalities complement each other in the evaluation of surgical portosystemic shunts. Interventional radiology plays an important role in the management of complications, such as shunt thrombosis and stenosis. This article describes the various types of surgical portosystemic shunts, explains the anatomy and pathophysiology of these shunts, illustrates the pearls and pitfalls of different imaging modalities in the assessment of these shunts and demonstrates the role of radiologists in the interventional management of complications.

Pancreatitis and portal vein thrombosis in children: the chicken or the egg causality dilemma

BACKGROUND

The association of pancreatitis and portal vein thrombosis (PVT) is extremely rare in children. We report on 3 cases which suggest that there may be a causal relation between the two.

METHODS

Clinical characteristics and evolution of 3 children with this particular condition were analyzed retrospectively. In this group of patients, the strategy consisted in opting for early surgical decompression of the portal hypertension, which was followed by a favorable outcome, not only in terms of complications related to the portal hypertension but also of a contemporaneous spontaneous regression of the concurrent pancreatic disease, in absence of any other specific management of the latter problem.

RESULTS AND CONCLUSIONS

Combined PVT and pancreatitis is exceptional in children. Although this series is small, it provides insight and some evidence that the pancreatic disease might be secondary to the cavernomatous transformation of the regional venous system. More interestingly, it suggests that the appropriate management strategy should be to rapidly relieve portal hypertension after resolution of the acute phase of pancreatitis.

Meso-Rex bypass to manage prehepatic portal hypertension after the failure of an intrahepatic portosystemic stent shunting

A cavernomatous transformation of the extrahepatic portion of the portal vein is a common cause of chronic portal hypertension in children. A few attempts at radiological interventions have been reported, but have rarely been successful. In this report, a surgical Meso-Rex bypass was performed to treat complicated prehepatic portal hypertension, after the insertion of an intrahepatic stent for portosystemic shunting had failed. The review of this case nicely illustrates how differently effective are these two shunting procedures-in terms of restoring hepatopetal flow, managing portal hypertension, and establishing-or not-portosystemic connections.

Partial splenectomy and use of splenic vein as an autograft for meso-Rex bypass: a clinical observational study

Background

Meso-Rex bypass (MRB) surgery is being increasingly used to treat chronic prehepatic portal hypertension secondary to extrahepatic portal vein thrombosis (EPVT) and cavernous transformation (EPVCT) in children. Rather than using the internal jugular vein (IJV, the traditional venous graft), we used an autogenous splenic vein segment graft for MRB.

Material/Methods

We examined 25 children with extrahepatic portal hypertension and a history of recurrent upper gastrointestinal (GI) variceal bleeding despite previous endoscopic sclerotherapy. All patients had melena, splenomegaly, hypersplenism, or some combination thereof. Left portal vein (LPV) patency was verified in 22 patients using intraoperative direct portography through the umbilical vein. Partial splenectomy was performed to enable the harvest of the splenic vein trunk, which was anastomosed between the superior mesenteric vein (SMV) and the left portal vein (LPV). All patients were followed for 12–48 months (mean=25.6 months) and no patients were lost to follow-up.

Results

Preoperative Doppler ultrasound (US) imaging indicated that 18/25 patients had adequate intrahepatic portal veins for shunting, with no blood flow in the LPVs of 7 patients. LPV patency in 22/25 patients was verified using intraoperative direct portography, with successful MRB. Shunting was converted into a portosystemic shunt in the remaining 3/25 patients with thrombosed LPVs. A Doppler US evaluation of the vein conduit revealed excellent postoperative flow. The patients’ mean hemoglobin, platelet, and white blood cell counts increased significantly, and in all cases the endoscopic status obviously improved after shunting. Occlusion or narrowing occurred in 2/22 patients after discharge. At 12 months (for 1 patient) and 24 months (for 1 patient), the shunt was converted into a portosystemic shunt. The cumulative graft patency rate was 91% (20/22).

Conclusions

Partial splenectomy and splenic vein autografting in MRB surgery can successfully resolve prehepatic portal hypertension and hypersplenism in children.

Intrahepatic portal venous systems in children with noncirrhotic prehepatic portal hypertension: anatomy and clinical relevance

BACKGROUND

Children with extrahepatic portal hypertension typically present with cavernomatous transformation of the portal vein and a poorly defined intrahepatic portal vein system on conventional imaging. With the Meso-Rex Bypass becoming the gold-standard intervention for a cure, a precise assessment of the intrahepatic portal vein system provides helpful data for deciding whether a Meso-Rex Bypass is feasible or not.

METHODS

All children with extrahepatic portal hypertension were prospectively assessed by wedged hepatic venous portography. Venous anatomy was categorized into five subtypes (A to E), depending on the presence of thrombosis in the Rex recessus, or not, and its extension within the intrahepatic portal venous system.

RESULTS

Eighty-nine children entered the study. Previous umbilical vein catheterization is usually associated with Rex thrombosis, while the Rex recessus and the intrahepatic portal venous system are patent in idiopathic cases, thus allowing for the performance of a Meso-Rex Bypass with a good outcome.

CONCLUSIONS

Wedged hepatic venous portography is a very effective tool for detailed preoperative assessment and identification of children being considered for Meso-Rex Bypass surgery. An anatomic-radiological classification is useful in selecting patients for Meso-Rex Bypass with anticipation of a high rate of success.

Non-cirrhotic portal hypertension

Non-cirrhotic portal hypertension (NCPH) encompasses a wide range of disorders, primarily vascular in origin, presenting with portal hypertension (PHT), but with preserved liver synthetic functions and near normal hepatic venous pressure gradient (HVPG). Non-cirrhotic portal fibrosis/Idiopathic PHT (NCPF/IPH) and extrahepatic portal venous obstruction (EHPVO) are two prototype disorders in the category. Etiopathogenesis in both of them centers on infections and prothrombotic states. Presentation and management strategies focus on repeated well tolerated episodes of variceal bleed and moderate to massive splenomegaly and other features of PHT. While the long-term prognosis is generally good in NCPF, portal biliopathy and parenchymal extinction after prolonged PHT makes outcome somewhat less favorable in EHPVO. While hepatic schistosomiasis, congenital hepatic fibrosis and nodular regenerative hyperplasia have their distinctive features, they often present with NCPH.

Renal blood flow before and after portosystemic shunt in children with portal hypertension

INTRODUCTION

Variceal haemorrhage in children with extrahepatic portal hypertension is best controlled by an effective decompressive shunt, but long-term follow up of children who have had splenorenal shunt due to extrahepatic portal hypertension (EHPH) gave evidence for assuming the risk of renal venous hypertension (RVH).

PURPOSE

To study renal hemodynamic before and after portal decompression.

METHODS

The results of 144 portosystemic shunt operations were followed from 2005 to 2013. Seventy-two patients applied central splenorenal shunt (CSS) with splenectomy, ten side-to-side splenorenal shunt without splenectomy (SRSss), ten patients assessed the distal splenorenal shunt (DSS). Forty-three iliacomesenterial anastomosis (IMA) and in nine cases performed mesocaval anastomosis (MCA). Children had a standard pre- and postoperative work up including gastrointestinal endoscopy, Doppler ultrasonography (US), multi-slice computed tomography (MSCT) and renography.

RESULTS

In 11 (15.2 %) patients after CSS on duplex, Doppler study revealed signs of impeded venous outflow on the left renal vein (LRV). At long-term follow-up PI and RI of left renal artery remained at high numbers (1.48 ± 0.17 and 0.72 ± 0.19, p ≤ 0.05, respectively) after the CSS. Venous blood flow in the LRV at the hilum showed slower speed performance in groups of CSS and after IMA. After DSS, these signs have not been detected. Four patients after IMA on US Doppler and CT angiography revealed dilated left testicular and ovarian veins, with retrograde blood flow in them, which clinically manifested as left flank pain, macro- and microhematuria, varicocele and ovaricocele.

CONCLUSION

The study shows that CSS and IMA more negatively effect on hemodynamics of left kidney and symptoms of RVH obviously due to shunting the large amounts of blood from a system of high pressure to a low.

Management of late-onset portal vein complications in pediatric living-donor liver transplantation

The purpose of this study was to evaluate retrospectively the results of PTA for late-onset PV complications after pediatric LDLT and to assess whether a meso-Rex shunt is a viable option for treating restenosis of the PV after PTA in selected cases. Seventy-five children who underwent adult-to-child LDLT were included in this study, and there were six late-onset PV complications (8.0%). The initial therapeutic approach was PTA, with or without stent: PTA with balloon dilation for three children, PTA with stent placement for one child, and failure to cannulate the occluded PV for two children. A meso-Rex shunt was performed in the two children after failed PTA: One suffered complete obstruction of the main PV, and the other, restenosis with total thrombosis after PTA with stent. The PTA was a technical and clinical success in four with PV stenosis of the six patients (66.7%), and successful application of a meso-Rex shunt in the other two children resulted in restoration of PV flow. In conclusion, PTA is a safe and effective procedure for treating late-onset PV stenosis after pediatric LDLT. However, in growing pediatric recipients with restenosis of the PV after PTA or chronic PV thrombosis, a meso-Rex shunt may be a better choice for late-onset PV complications.

Portal cavernoma cholangiopathy: consensus statement of a working party of the Indian national association for study of the liver

Portal cavernoma cholangiopathy (PCC) is defined as abnormalities in the extrahepatic biliary system including the cystic duct and gallbladder with or without abnormalities in the 1st and 2nd generation biliary ducts in a patient with portal cavernoma. Presence of a portal cavernoma, typical cholangiographic changes on endoscopic or magnetic resonance cholangiography and the absence of other causes of these biliary changes like bile duct injury, primary sclerosing cholangitis, cholangiocarcinoma etc are mandatory to arrive a diagnosis. Compression by porto-portal collateral veins involving the paracholedochal and epicholedochal venous plexuses and cholecystic veins and ischemic insult due to deficient portal blood supply or prolonged compression by collaterals bring about biliary changes. While the former are reversible after porto-systemic shunt surgery, the latter are not. Majority of the patients with PCC are asymptomatic and approximately 21% are symptomatic. Symptoms in PCC could be in the form of long standing jaundice due to chronic cholestasis, or biliary pain with or without cholangitis due to biliary stones. Endoscopic retrograde cholangiography has no diagnostic role because it is invasive and is associated with risk of complications, hence it is reserved for therapeutic procedures. Magnetic resonance cholangiography and portovenography is a noninvasive and comprehensive imaging technique, and is the modality of choice for mapping of the biliary and vascular abnormalities in these patients. PCC is a progressive condition and symptoms develop late in the course of portal hypertension only in patients with severe or advanced changes of cholangiopathy. Asymptomatic patients with PCC do not require any treatment. Treatment of symptomatic PCC can be approached in a phased manner, coping first with biliary clearance by nasobiliary or biliary stent placement for acute cholangitis and endoscopic biliary sphincterotomy for biliary stone removal; second, with portal decompression by creating portosystemic shunt; and third, with persistent biliary obstruction by performing second-stage biliary drainage surgery such as hepaticojejunostomy or choledochoduodenostomy. Patients with symptomatic PCC have good prognosis after successful endoscopic biliary drainage and after successful shunt surgery.

Current therapeutic strategies for childhood hepatic tumors: surgical and interventional treatments for hepatoblastoma

Surgery is the mainstay of multimodal treatment for hepatoblastomas. Among the various staging systems used, PRETEXT is currently adopted in all major study groups worldwide as a common pretreatment staging system. Although variations of treatment strategies among study groups exist, the majority of hepatoblastoma cases currently undergo preoperative chemotherapy. It is therefore critical to determine the optimal surgical treatment during the initial courses of chemotherapy. Patients with PRETEXT IV tumors, multifocal tumors and tumors invading major vessels of the liver are candidates for liver transplantation. Liver transplantation requires preparation in advance, and consultation to a liver expertise team must take place no later than after two cycles of chemotherapy. The existence of pulmonary metastasis is a predictor of poor prognosis of the patient. Surgery for pulmonary nodules should be considered for those patients remaining positive after cycles of chemotherapy. A considerable number of patients have been reported to achieve long-term survival after resecting pulmonary metastasis. The existence of pulmonary metastasis at diagnosis is no longer a contraindication for liver transplantation, provided that the pulmonary nodules are eliminated by chemotherapy or by metastasectomy. Transcatheter arterial chemoembolization (TACE) is a useful tool for the local control of hepatoblastomas, although there are very few reports statistically supporting the significant advantage of this treatment modality. Based on individual cases, TACE could be beneficial in maximizing the anti-tumor effect with less toxic side effects.

Meso-Rex bypass for extrahepatic portal vein obstruction in children

Background

Meso-Rex bypass (MRB) and portosystemic surgical shunt (PSS) are both used to treat extrahepatic portal vein obstruction (EHPVO) in children. The aim of this study was to analyse the outcome of MRB and PSS to select patients who could benefit from a prophylactic MRB.

Methods

This single-centre retrospective study of children who underwent either MRB or PSS for EHPVO was conducted between 1996 and 2010. Details of patient demographics and preoperative evaluation were collected. Success rates, defined as shunt patency after a minimum of 6 months and clearance of varices or symptoms, were compared. Determinants of outcomes were explored.

Results

Sixty-nine patients underwent a MRB or PSS. Median (interquartile range, i.q.r.) age at surgery was 6·6 (4·0–10·6) years. Twenty-four patients (35 per cent) had had a neonatal umbilical catheter (NUC) placed previously and 47 (68 per cent) had experienced an upper gastrointestinal bleed. Imaging assessment of the intrahepatic left portal vein was considered favourable in 40 patients. Of 43 MRBs attempted, 11 failed during surgery and four patients had persistent thrombosis after a median of 55 (i.q.r. 18–107) months. The success rate of MRB was 60 per cent (26 of 43) compared with 100 per cent (26 of 26) for PSS (P &lt; 0·001). It was lower among patients in whom a NUC had been used (2 of 10 versus 24 of 33; P = 0·004), for procedures undertaken early in the series (6 of 16 versus 20 of 27; P = 0·020) and when the imaging pattern was unfavourable (0 of 5 versus 26 of 38; P = 0·006). On multivariable analysis, only a previous history of NUC predicted failure (P = 0·016).

Conclusion

Prophylactic MRB seems a good treatment option for EHPVO in children, but should be done only by an experienced team in patients with favourable imaging and without a previous history of NUC.

Presented in part to the 43rd Annual Meeting of the American Pediatric Surgical Association, San Antonio, Texas, USA, May 2012

Evaluation of Rex Shunts

The purpose of the Rex shunt is to restore normal blood flow to a hemodynamically compromised liver that is otherwise normal. It has proven to be an effective treatment for children with extrahepatic portal vein thrombosis as in the case presented. The shunt allows blood from the superior mesenteric vein to bypass the obstructed extrahepatic portal vein and enter the liver through the still patent left portal vein. The operation is successful in more than 90% of patients. The name “Rex shunt” is derived from the location in the liver in which the shunt is placed, the area between segments three and four of the left lobe of the liver.