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Journal of Pediatric Surgery (2011) 46, 749–752

Successful mesenterico-left portal vein bypass in a childwith duplicated round ligaments and rex recessi☆

Timothy B. Lautz⁎, Alex Dzakovic, Riccardo A. Superina

Department of Surgery, Children's Memorial Hospital, Feinberg School of Medicine of Northwestern University, Box 57,Chicago, IL 60614, USA

Received 3 December 2010; revised 17 December 2010; accepted 21 December 2010

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Key words:Portal vein obstruction;Mesenterico-left portalvein bypass;

Rex shunt;Rex recessus;Umbilical vein

Abstract A 3-year-old girl with idiopathic extrahepatic portal vein obstruction undergoing mesenterico-left portal vein bypass (MLPVB), or Rex shunt, for recurrent variceal bleeding was intraoperativelydiscovered to have duplicated round ligaments and Rex recessi. The left and right portal veins connectedto their respective round ligaments but had minimal communication within the liver. Intraoperativevenography identified a better preserved portal system on the left, and standard MLPVB resulted inexcellent shunt flow. The shunt remains patent and the patient asymptomatic 9 months after heroperation. Abnormal portal anatomy is not a contraindication to MLPVB.© 2011 Elsevier Inc. All rights reserved.

Mesenterico-left portal vein bypass (MLPVB), or Rexshunt, is now the standard treatment for children withsymptomatic extrahepatic portal vein obstruction (EHPVO)[1,2]. In the standard MLPVB, a jugular vein graft connectsthe superior mesenteric vein to the left portal vein withinthe Rex recessus of the liver [3]. The Rex recessus isidentified by tracing the round ligament (obliteratedumbilical vein) to its connection with the left portal vein.Flow to the right portal system relies on communicationfrom the left side. We report the case of a 3-year-old girlwith EHPVO and abnormal portal anatomy. The implica-tions of congenital hepatobiliary anomalies on the feasibil-ity of MLPVB are discussed.

☆ There are no disclaimers or sources of funding or support to report.⁎ Corresponding author. Tel.: +1 773 883 6187.E-mail address: t-lautz@northwestern.edu (T.B. Lautz).

022-3468/$ – see front matter © 2011 Elsevier Inc. All rights reserved.oi:10.1016/j.jpedsurg.2010.12.017

1. Case report

A 3-year-old girl was found to have cavernoustransformation of the portal vein with multiple collateralvessels on abdominal computed tomography (CT) scanperformed to evaluate an upper gastrointestinal bleed.Esophagogastroduodenoscopy identified grade IV varices,which were banded. She was subsequently referred to ourservice for MLPVB.

The patient did not have a history of prematurity,umbilical vein catheterization, or neonatal sepsis. She hadno other cardiac or hepatobiliary conditions and was healthyand age appropriate before the onset of gastrointestinalbleeding. A thorough hypercoaguable workup revealedno abnormality.

On preoperative review of her contrast-enhanced abdom-inal CT scan, she was noted to have a reasonably well-preserved intrahepatic portal vein. No other structural

Fig. 1 Intraoperative photograph demonstrating the duplicated round ligaments leading to dissected out left and right Rex recessi. Yellowarrows indicate the right round ligament at its connection with the right portal vein, whereas blue arrowheads indicate the left round ligament atits connection with the left portal vein.

750 T.B. Lautz et al.

anomalies of the liver or round ligaments were noted. She,therefore, underwent abdominal exploration with plannedMLPVB and recourse to distal splenorenal shunt if MLPVBwere not possible. Upon exploration, she was noted to haveduplicated round ligaments leading to 2 separate Rex recessi.The left round ligament led to the usual recessus betweensegments II/III and IV. However, the right round ligamentled to an abnormal recessus immediately to the left of thegallbladder, at the junction between the right and left lobesof the liver.

Both Rex recessi were meticulously dissected out todelineate the anatomy and determine if either led to a patentintrahepatic portal vein (Fig. 1). Venograms were performedthrough both round ligaments (Fig. 2). The right roundligament connected with the right portal venous system, with

Fig. 2 Intraoperative portal venograms via the right (A) and left (B) roucommunication. The left portal system is better preserved than the right.

minimal crossover to the left (Fig. 2A). The left roundligament connected to the left portal vein (Fig. 2B). Again,there was little intrahepatic crossover within the portalsystem; however, the left portal venous system was found tobe better preserved. In addition, the back bleeding from theleft portal vein was brisker, and it was, therefore, selected forthe distal anastomosis.

Standard MLPVB was performed using a jugular veingraft connecting the superior mesenteric vein with the leftportal vein within the left Rex recessus. Shunt flow wasmeasured using a Doppler flow probe at 170 to 220 mL/min,which represents 60% to 80% of expected portal flow for thechild's size. Her postoperative course was uneventful.Routine CT angiogram performed 6 days after surgerydemonstrated a patent Rex shunt with opacification of both

nd ligaments. The left and right portal systems demonstrate minimal

Fig. 3 Postoperative contrast-enhanced CT reconstructiondemonstrates a patent MLPVB with opacification of the left(LPV) and right (RPV) intrahepatic portal veins.

751MLPVB with duplicated round ligaments and rex recessi

the left and right portal systems (Fig. 3). At her 9-monthfollow-up, she remained symptom free, and duplex ultra-sound confirmed shunt patency.

2. Discussion

We present the case of a 3-year-old girl with duplicatedround ligaments connected to separate, poorly communicat-ing left and right portal veins within separate Rex recessi.Congenital anomalies of the portal system are rarelyimplicated as the etiology for EHPVO. The aberrant anatomywas not readily apparent on preoperative imaging. Thisanatomy did not prevent successful restoration of intrahepa-tic portal flow with the MLPVB.

Mesenterico-left portal vein bypass has emerged as thepreferred treatment option for children with EHPVO[1,2,4,5]. It not only relieves variceal bleeding and othersymptoms of portal hypertension but also restoresphysiologic portal flow with important metabolic con-sequences. The MLPVB has been shown to improveneurocognitive function [6], correct coagulopathy [7], andreverse growth failure [8], in addition to providing durablerelief from variceal bleeding. Our current practice is toevaluate all patients with symptomatic EHPVO forMLPVB. In cases where MLPVB is not feasible, apalliative surgical option such as the Warren shunt maybe offered to relieve the symptoms of portal hypertension.Surgeons caring for children with EHPVO should havecomfort and familiarity with all current treatment options,including endoscopic procedures, palliative shunts, andespecially the restorative MLPVB.

Abnormalities of the umbilical veins have a widespectrum of presentation. The umbilical veins are paired atthe third gestational week and empty into the fetal heart.However, by the sixth or seventh gestational week, the leftumbilical vein normally connects with the hepatic sinusoidsto help form the portal system and ductus venosus, whereas

the right umbilical vein involutes. Persistent duplication ofthe umbilical vein, which results in a 4-vessel cord, is rareand has only been previously reported in isolated casereports. Presentation has ranged from stillborn with multiplecongenital anomalies [9] to normal term delivery with noassociated abnormalities [10-12]. On the other hand,persistent right umbilical vein may occur as frequently as 1in 500 live births [13]. In this situation, the left umbilical veininvolutes but the right umbilical vein persists. Recent reportssuggest that persistent right umbilical vein is not usuallyassociated with congenital anomalies [13-15].

Although most cases of EHPVO are idiopathic, they aregenerally believed to result from postnatal events. Extrahe-patic portal vein obstruction has been reported to occur afterumbilical vein catheterization, after neonatal sepsis, and inchildren with hypercoaguable disorders. However, in thispatient, an intrauterine event is the most likely cause ofEHPVO. Occlusion of the left umbilical vein before the sixthgestational week is believed to cause persistent rightumbilical vein. An incomplete occlusion of the left umbilicalvein may have prevented the right side from involuting.However, further cavernous change in the portal veinresulted in portal hypertension and the eventual needfor MLPVB.

This case serves as an extreme and unusual examplerepresentative of a much more common dilemma in theoperative management of EHPVO. Intraoperative venogramfrequently demonstrates poor communication between theleft and right portal systems. Nonetheless, relief of portalhypertension and adequate portal flow can usually beobtained by anastomosis to the isolated left portal system.Such as in this case, adaptation occurs, and flow to the rightportal typically develops via intra- or extrahepatic collaterals.Perceived lack of flow to the right portal system at the initialoperation should not discourage the experienced surgeonfrom attempting MLPVB.

Technical challenges are common in the surgicaltreatment of EHPVO with MLPVB. However, even majorcongenital hepatic anomalies do not preclude successfulrestoration of portal flow using MLPVB. Identifying thenuances of portal anatomy on preoperative imaging remainschallenging. Operative exploration with meticulous dissec-tion of the Rex recessus (or recessi), determination of backbleeding from the intrahepatic portal vein, and/or directportal venography remain the gold standard for assessingportal anatomy and the feasibility of MLPVB.

References

[1] Superina R, Bambini DA, Lokar J, et al. Correction of extrahepaticportal vein thrombosis by the mesenteric to left portal vein bypass.Ann Surg 2006;243:515-21.

[2] Superina R, Shneider B, Emre S, et al. Surgical guidelines for themanagement of extra-hepatic portal vein obstruction. Pediatr Trans-plant 2006;10:908-13.

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[3] Bambini DA, Superina R, Almond PS, et al. Experience with the Rexshunt (mesenterico-left portal bypass) in children with extrahepaticportal hypertension. J Pediatr Surg 2000;35:13-8.

[4] Dasgupta R, Roberts E, Superina RA, et al. Effectiveness of Rex shuntin the treatment of portal hypertension. J Pediatr Surg 2006;41:108-12discussion 108-112.

[5] de Ville de Goyet J, Alberti D, Clapuyt P, et al. Direct bypassingof extrahepatic portal venous obstruction in children: a newtechnique for combined hepatic portal revascularization andtreatment of extrahepatic portal hypertension. J Pediatr Surg1998;33:597-601.

[6] Mack CL, Zelko FA, Lokar J, et al. Surgically restoring portal bloodflow to the liver in children with primary extrahepatic portal veinthrombosis improves fluid neurocognitive ability. Pediatrics 2006;117:e405-12.

[7] Mack CL, Superina RA, Whitington PF. Surgical restoration ofportal flow corrects procoagulant and anticoagulant deficienciesassociated with extrahepatic portal vein thrombosis. J Pediatr 2003;142:197-9.

[8] Lautz TB, Sundaram SS, Whitington PF, et al. Growth impairment inchildren with extrahepatic portal vein obstruction is improved bymesenterico-left portal vein bypass. J Pediatr Surg 2009;44:2067-70.

[9] Painter D, Russell P. Four-vessel umbilical cord associated withmultiple congenital anomalies. Obstet Gynecol 1977;50:505-7.

[10] Perez-Cosio C, Sheiner E, Abramowicz JS. Four-vessel umbilicalcord: not always a dire prognosis. J Ultrasound Med 2008;27:1389-91.

[11] Rodriguez MA. Four-vessel umbilical cord without congenitalabnormalities. South Med J 1984;77:539.

[12] Schimmel MS, Eidelman AI. Supernumerary umbilical vein resultingin a four-vessel umbilical cord. Am J Perinatol 1998;15:299-301.

[13] Wolman I, Gull I, Fait G, et al. Persistent right umbilical vein: incidenceand significance. Ultrasound Obstet Gynecol 2002;19:562-4.

[14] Kirsch CF, Feldstein VA, Goldstein RB, et al. Persistent intrahepaticright umbilical vein: a prenatal sonographic series without significantanomalies. J Ultrasound Med 1996;15:371-4.

[15] Yang PY, Wu JL, Yeh GP, et al. Prenatal diagnosis of persistent rightumbilical vein using three-dimensional sonography with powerDoppler. Taiwan J Obstet Gynecol 2007;46:43-6.