Technical dilemma in living-donor or split-liver transplant

In partial liver transplantation for adults criteria for the extent of reconstruction of middle hepatic vein tributaries have not been clarified. After hepatic venous and portal anastomoses in living-donor liver transplantation using left liver graft without middle hepatic vein, color Doppler ultrasonography was applied to check venous and portal blood flow. Color Doppler ultrasonography demonstrated absent hepatic venous flow and reversed portal venous flow in the congested area of the left paramedian sector which had been drained by the divided branch of the middle hepatic vein. The area was darkly discolored before arterial reperfusion and under clamping of the artery. Reconstruction of the venous branch was added after arterial anastomosis. Color Doppler ultrasonography revealed restored normal venous outflow and portal inflow after venous reconstruction. Postoperative course of the recipient was uneventful with rapid recovery of liver function. We propose that middle hepatic vein tributaries should be reconstructed if color Doppler ultrasonography demonstrates absent venous flow and reversed portal flow, and if the liver volume excluding the discolored area under occlusion of the hepatic artery is estimated to be insufficient for postoperative metabolic demand.     

CEUS： A new imaging approach for postoperative vascular complications after right-lobe LDLT

AIM： To investigate contrast-enhanced ultrasound （CEUS） for early diagnosis of postoperative vascular complications after right-lobe living donor liver transplantation （RLDLT）. METHODS： The ultrasonography results of 172 patients who underwent RLDLT in West China Hospital, Sichuan University from January 2005 to June 2008 were analyzed retrospectively. Among these 172 patients, 16 patients＇ hepatic artery flow and two patients＇ portal vein flow was not observed by Doppler ultrasound, and 10 patients＇ bridging vein flow was not shown by Doppler ultrasound and there was a regional inhomogeneous echo in the liver parenchyma upon 2D ultrasound. Thus, CEUS examination was performed in these 28 patients. RESULTS： Among the 16 patients without hepatic artery flow at Doppler ultrasound, CEUS showed nine cases of slender hepatic artery, six of hepatic arterial thrombosis that was confirmed by digital subtraction angiography and/or surgery, and one of hepatic arterial occlusion with formation of lateral branches. Among the two patients without portal vein flow at Doppler ultrasound, CEUS showed one case of hematoma compression and one of portal vein thrombosis,and both were confirmed by surgery. Among the 10 patients without bridging vein flow and with liver parenchyma inhomogeneous echo, CEUS showed regionally poor perfusion in the inhomogeneous area, two of which were confirmed by enhanced computed tomography （CT）, but no more additional information about bridging vein flow was provided by enhanced CT. CONCLUSION： CEUS may be a new approach for early diagnosis of postoperative vascular complications after RLDLT, and it can be performed at the bedside.     

Comparison of Doppler ultrasonography and the hepatic venous pressure gradient in assessing portal hypertension in liver cirrhosis

BACKGROUND AND AIM: This prospective study aimed to determine whether Doppler ultrasonography can represent the hepatic venous pressure gradient (HVPG) as an assessment of the severity of portal hypertension and the response to terlipressin, which reduces the portal pressure in liver cirrhosis. METHODS: The HVPG and the Doppler ultrasonographic parameters, such as the portal venous velocity and the splenic venous velocity, the pulsatility and the resistive index of the hepatic, splenic and renal arteries were measured in 138 patients with liver cirrhosis. The changes in the HVPG and the portal venous velocity after administering terlipressin were evaluated in 43 of the 138 patients. The patients who showed a reduction in the HVPG of more than 20% of the baseline were defined as responders to terlipressin. RESULTS: None of the Doppler ultrasonographic parameters correlated with the HVPG. Both the HVPG (28.0 +/- 19.8%) and the portal venous velocity (29.7 +/- 13.2%) showed a significant reduction after terlipressin administration. However, the portal venous velocity decreased significantly, not only in the responders (31.0 +/- 12.0%) but also in the non-responders (25.2 +/- 16.4%). CONCLUSIONS: Doppler ultrasonography does not represent the HVPG, and is therefore not suitable for replacing HVPG as a means of assessing the severity of portal hypertension and the response to drugs which reduce the portal pressure in liver cirrhosis.     

Doppler ultrasonography for postoperative hepatofugal portal blood flow of the intrahepatic portal vein

BACKGROUND/AIMS: The clinical significance of the hepatofugal portal blood flow after abdominal surgery involving other than portosystemic shunt was investigated in our hepatobiliary pancreatic surgical division. METHODOLOGY: Preoperative and postoperative Color and pulsed Doppler ultrasonography was performed on 101 consecutive patients who underwent abdominal surgery. Preoperative Doppler ultrasonography was performed within one week before surgery. Basically, postoperative Doppler ultrasonography was performed every other day within one week after surgery and once a week 2 weeks after surgery. The portal flow direction was assessed in the right portal branch or the umbilical portion of the left portal branch. RESULTS: Of the 101 patients, 9 showed a hepatofugal flow in the intrahepatic portal vein, 5 of which showed a total hepatofugal flow, and 4 of these 5 patients died of hepatic failure. The remaining 4 patients showed a partial hepatofugal flow and postoperative hyperbilirubinemia, but all 4 survived. CONCLUSIONS: Postoperative total hepatofugal flow indicated a serious prognostic sign of critical liver damage. Postoperative partial hepatofugal flow induced postoperative hyperbilirubinemia which was not critical.     

Colour Doppler ultrasonography of a segmental branch of the portal vein is useful for early diagnosis and monitoring of the therapeutic course of veno-occlusive disease after allogenic haematopoietic stem cell transplantation

We report two cases in which visualization of the segmental branch of the hepatic portal vein with the colour Doppler ultrasonography (US) technique was useful for the early diagnosis of veno-occlusive disease. The change in blood flow in the segmental branch of the portal vein occurred 5 and 6 d before the clinical criteria were fulfilled in the two cases. Reverse flow in the segmental branch began partially in the liver at first, and then spread to the whole liver several days later. All the US findings in both cases disappeared after thrombolytic therapy.     

Utility of Doppler ultrasonography for diagnosing and assessing treatment effects in liver compartment syndrome

Liver compartment syndrome is a life-threatening complication of hepatic subcapsular hematoma; diagnosis and assessment of treatment effects are therefore important. We report a rare case of liver compartment syndrome due to spontaneous hepatic subcapsular hematoma without any underlying conditions, in which Doppler ultrasonography (US) proved useful in both diagnosis and assessment of treatment effects. A 32-year-old woman experienced sudden epigastralgia and was diagnosed with hepatic subcapsular hematoma in the right lobe, based on contrast-enhanced computed tomography. Hepatic arteriography showed active hemorrhage and Doppler US showed retrograde flow in the right portal vein. From these findings, we diagnosed hepatic subcapsular hematoma complicated with liver compartment syndrome, and performed embolization of the bleeding point and percutaneous hematoma drainage. After these medical procedures, normalized antegrade flow in the right portal vein was observed on Doppler US. No underlying conditions contributing to hematoma were identified. In this case, Doppler US was useful for both diagnosis and assessment of treatment effects in liver compartment syndrome. When we examine patients with hepatic subcapsular hematoma, Doppler US should be used to diagnose the presence of liver compartment syndrome and assess treatment effects.     

Asymptomatic portal vein obstruction after hepatobiliary resection: early detection by Doppler ultrasonography

We report two different types of portal vein obstruction after liver resection: portal vein thrombosis due to steal phenomenon via a splenorenal shunt, and kinking of the skeletonized left portal vein after right hepatic lobectomy with caudate lobectomy. The two cases of portal vein obstruction were asymptomatic without any suggestive laboratory findings. Only routine Doppler ultrasonography detected portal vein obstruction which was successfully treated by emergency operation.     

Ultrasonography of the liver. An update on new applications

Sonography is highly useful in evaluating the patient with severe liver disease before and after the placement of a TIPS and before and after organ transplantation. Efforts to use ultrasound imaging to evaluate for primary and metastatic lesions to the liver have been reviewed. With its Doppler and color flow capabilities, ultrasound imaging will remain an important modality for hepatic imaging, especially in the evaluation of portal vein patency and hepatic artery thrombosis.     

Hepatic vascular malformations in hereditary hemorrhagic telangiectasia

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant vascular disorder that can involve the liver diffusely in the form of vascular malformations ranging from small telangiectases to discrete arteriovenous malformations. Anatomically, three different patterns of abnormal vascular communications can occur in liver: portal vein to hepatic vein (portovenous), hepatic artery to hepatic vein (arteriovenous) and hepatic artery to portal vein (arterioportal), with the most common being arteriovenous. Only 5 to 8% of patients with these vascular malformations are symptomatic. When symptomatic, patients present with high-output cardiac failure, biliary ischemia (which, when severe, can progress to biliary and hepatic necrosis and lead to acute liver failure), or portal hypertension. Other less common presentations include portosystemic encephalopathy and abdominal angina. Diagnosis is confirmed by Doppler ultrasonography or multidetector computed tomography. The hallmark findings are intrahepatic hypervascularization and an enlarged common hepatic artery. Focal nodular hyperplasia and nodular regenerative hyperplasia are common findings. Symptomatic patients are treated with intensive medical treatment aimed at the predominant clinical presentation. Patients who fail aggressive medical therapy and those with acute biliary/hepatic necrosis should be considered for liver transplantation.     

实时灰阶超声造影在肝肿瘤诊断中的价值

目的:评价实时灰阶超声造影在肝肿瘤诊断中的价值.方法:利用实时灰阶超声造影观察50例54个肝实质性肿块的动态增强表现作出造影诊断,并与病理对照.结果:除2例少血供胃肠道肝转移癌、1例手术后疤痕及1例炎性假瘤未见增强外,其余肿块均有不同程度的增强.肝恶性肿块早期动脉相强化,消失较快;肝血管瘤(HCH)增强速度较慢,呈周边强化;肝局灶性结节性增生(FNH)早期动脉相强化,但持续时间较长;肝硬化结节与肝实质呈同步强化.如以动脉相增强呈高回声而门脉相消失呈低回声考虑为肝恶性肿瘤,则本组超声造影诊断肝恶性肿瘤的敏感性、特异性及准确性分别为91.7%(33/36),100%(18/18)和94.4%(51/54).结论:实时灰阶超声造影可得到丰富的肝肿瘤供血及血流灌注信息,对肝肿瘤的诊断、鉴别诊断有重要的临床应用价值.     

Analysis of Hepatic Vein Waveform by Doppler Ultrasonography in 100 Patients with Portal Hypertension

Objectives : We classified the Doppler waveform seen in patients with portal hypertension and examined the associations of the waveform type with the diagnosis of Budd-Chiari syndrome and severity of the liver cirrho-sis. Methods : The Doppler pattern of right and left hepatic veins in 100 consecutive Japanese patients with portal hypertension and esophagogastric varices was classified into six types: 1, triphasic waveform; IF, bi-phasic waveform without reversed flow; III, decreased amplitude of phasic oscillations; IV, flat waveform with fluttering; V, completely flat waveform with fluttering; VI, no waveform. All patients underwent computed tomography and magnetic resonance imaging. Patients in whom hepatic vein waveform showed type IV, type V, or type VI, positively underwent hepatic venography and inferior vena cavography. Resuits: Type I was seen in 31 of 100 patients, type II in 35, type III in 17, type IV in eight, type V in four, and type VI in five. Types I-IV waveform indicated no lesion in hepatic veins and inferior vena cava, type V indicated stenosis of hepatic veins or occlusion of inferior vena cava, and type VI, occlusion of hepatic veins. For one patient with type V hepatic veins, halloon angioplasty was done, and the waveform changed from type V to type II. Examining the relationship between hepatic vein waveform and the Child-Pugh score, liver function of type IV cases was worse than tbat of type I cases in 66 cirrhotie patients witbout bepatocellular carcinoma(p < 0.05). Tbere was no clear relutionship between bepatic vein waveform and portal venous perfusion, as based on Nordlinger's grade. Conclusions: Our classiflcation of hepatic vein waveform in Doppler ultrasonography is useful in di-agnosing Budd-Cbiari syndrome, in judging the effi-ciency of treatment for bepatic vein lesions, and in assessing severe liver function in cirrbotic patients.     

Modified arterialization of orthotopic liver transplantation in a mouse model

BACKGROUND:With the establishment of genetically modified and gene knock-out models,the mouse has become an important animal model for liver transplantation.We examined hepatic rearterialization after liver transplantation in a mouse model.METHODS:Orthotopic liver transplantation was performed in 70 mice and sham-operation was performed in a control group of 40 mice.Based on the"two-cuff"method,a continuous suture approach was applied to the suprahepatic inferior vena cava and a cuff approach to the portal vein and the infrahepatic inferior vena cava.A biliary stent was inserted into the bile duct.The hepatic artery was reconstructed with end-to-side anastomosis.The survival rate of recipients was monitored at 24 hours,one week,and one month after the operation.Liver function and morphology were evaluated one month postoperatively.RESULTS:Postoperative survival rates were 94.3%at 24 hours, 91.4%at one week,and 85.7%at one month.No significant difference was seen between the experimental and control groups in liver function.The hepatic tissue preserved normal structure.CONCLUSION:Owing to its high survival rate and stability, this surgical approach is ideal for establishing an orthotopic liver transplantation mouse model with hepatic artery reconstruction.     

Doppler ultrasonography in living donor liver transplantation recipients: Intra- and post-operative vascular complications

Living-donor liver transplantation has provided a solution to the severe lack of cadaver grafts for the replacement of liver afflicted with end-stage cirrhosis, fulminant disease, or inborn errors of metabolism. Vascular complications remain the most serious complications and a common cause for graft failure after hepatic transplantation. Doppler ultrasound remains the primary radiological imaging modality for the diagnosis of such complications. This article presents a brief review of intra- and post-operative living donor liver transplantation anatomy and a synopsis of the role of ultrasonography and color Doppler in evaluating the graft vascular haemodynamics both during surgery and post-operatively in accurately defining the early vascular complications. Intra-operative ultrasonography of the liver graft provides the surgeon with useful real-time diagnostic and staging information that may result in an alteration in the planned surgical approach and corrections of surgical complications during the procedure of vascular anastomoses. The relevant intraoperative anatomy and the spectrum of normal and abnormal findings are described. Ultrasonography and color Doppler also provides the clinicians and surgeons early post-operative potential developmental complications that may occur during hospital stay. Early detection and thus early problem solving can make the difference between graft survival and failure.     

超声造影检查在肝占位性病变诊断中的应用价值

背景:随着超声造影剂及其成像技术的迅速发展,超声造影技术的临床应用日趋成熟,为肝占位性病变的诊断提供了新手段.目的:分析各种不同的肝占位病变在超声造影检查中的表现,探讨其对该类疾病的诊断价值.方法:使用SonoVue造影剂对22例不同类型的肝占位性病变进行超声造影检查,同时以视频影像同步记录造影剂进入肝内血管、肝实质和肝占位性病变的时间和形态的变化.结果:不同类型的肝占位性病变在超声造影检查中显示出不同的动脉相、门静脉相和延迟相的变化.原发性肝癌以造影剂"快进快出"为主要表现;转移性肝癌以延迟相造影剂充盈缺损为主要表现;肝血管瘤以延迟相有显著的造影剂摄取为主要表现;肝脓肿以快速增强持续整个门静脉相和延迟相为主要表现;肝硬化结节则以与肝实质无法区分的同步强化为主要表现.结论:超声造影检查对肝占位性病变的定性诊断明显优于普通超声检查,在显示肿瘤数目,尤其是发现微小病灶方面优于增强CT,提高了超声检查对肝占位性病变的诊断价值.     

Change in portal flow after liver transplantation: effect on hepatic arterial resistance indices and role of spleen size

Information on changes in splanchnic hemodynamics after liver transplantation is incomplete. In particular, data on long-term changes are lacking, and the relationship between changes in arterial and portal parameters is still under debate. The effect of liver transplantation on splanchnic hemodynamics was analyzed with echo-Doppler in 41 patients with cirrhosis who were followed for up to 4 years. Doppler parameters were also evaluated in 7 patients transplanted for acute liver failure and in 35 controls. In cirrhotics, portal blood velocity and flow increased immediately after transplantation (from 9.1 plus minus 3.7 cm/sec to 38.3 plus minus 14.6 and from 808 plus minus 479 mL/min to 2,817 plus minus 1,153, respectively, P <.001). Hepatic arterial resistance index (pulsatility index) also augmented (from 1.36 plus minus 0.32 to 2.34 plus minus 1.29, P <.001) and was correlated with portal blood velocity and flow. The early changes in these parameters were related, in agreement with the hepatic buffer response theory. Portal flow returned to normal values after 2 years. Superior mesenteric artery flow normalized after 3 to 6 months. Splenomegaly persisted after 4 years, when spleen size was related to portal blood flow. In 7 patients transplanted for acute liver failure, portal flow, and hepatic arterial resistance index were normal after transplantation. In conclusion, a high portal flow was present in cirrhotics until 2 years after transplantation, probably because of maintenance of elevated splenic flow. An early increase in hepatic arterial resistance indices is a common finding, but it is transient and is related to the increase in portal blood flow. A normal time course of portal-hepatic hemodynamics was detected in patients transplanted for acute liver failure.     

Split liver transplantation for two adult recipients

We report a case of split liver transplantation for two adult recipients. The liver graft (1285 g) was split on the backtable into a right lobe graft (900 g, containing the inferior vena cava and middle hepatic vein) and a left lobe graft (385 g). The right lobe graft was implanted into a patient with hepatitis B cirrhosis uneventfully. The left lobe graft was implanted into a patient with familial amyloid polyneuropathy, but was met with massive bleeding from the transection surface and congestion of segment 4. The dusky appearance of segment 4 disappeared after hepatic artery anastomosis, but Doppler ultrasonography showed reverse blood flow in the segment 4 portal vein. Both patients survived the operation. The case illustrated that a left lobe graft without the middle hepatic vein could be problematic. To benefit two adults with chronic liver diseases, a better design of hepatic vein drainage of segment 4 in the left lobe graft and segment 5 and 8 in the right lobe graft is required.     

Reversal of portal flow after acute rejection in living-donor liver transplantation

Portal hepatofugal flow is rare after liver transplantation. We experienced a case in which hepatofugal portal flow was observed in acute rejection. A 6‐year‐old boy with glycogen storage disease type Ia underwent living‐donor liver transplantation. On postoperative day 7, portal venous peak velocity was markedly decreased without portal thrombosis and obstruction of the hepatic vein, and hepatic arterial peak velocity increased reciprocally. Based on a diagnosis of acute rejection, made on postoperative day 8, we initiated steroid pulse therapy. Despite the employment of this therapy, continuous hepatofugal portal flow was observed in the entire liver on postoperative day 8. On day 12, as the liver disorder progressed, the Doppler waveform in the portal vein changed from continuous to pulsatile hepatofugal flow. The patient died of liver failure on day 14. The histological findings of a biopsy specimen on day 9 showed centrilobular necrosis, while total hepatocellular necrosis was seen at autopsy. Hepatofugal flow after liver transplantation is considered to be an ominous sign caused by several factors, and its appearance indicates a fatal condition.     

First case of cadaveric liver transplantation in Japan

The first case of liver transplantation from a brain-dead donor in Japan is described. The recipient was a 43-year-old man with familial amyloid polyneuropathy who manifested various neuropathic symptoms and autonomic dysfunction at the time of transplantation. The graft had three arteries, for which a single trunk was created at the back table. A side-to-side cavacaval anastomosis was performed as an outflow reconstruction. To avoid portal congestion, a temporary shunt between the right posterior branch of the portal vein and the vena cava was constructed, instead of a venovenous bypass. The graft preservation time was 7.2 h and the operation time was 12.2 h. Although sufficient blood flow in the hepatic artery, portal vein, and hepatic vein was confirmed intra- and postoperatively, using Doppler ultrasound, transient graft dysfunction was observed immediately after surgery, but there was spontaneous improvement. The patient was discharged 100 days after transplantation.     

Nitric oxide synthase activity in the splanchnic vasculature of patients with cirrhosis: relationship with hemodynamic disturbances.

BACKGROUND/AIMS: It has been demonstrated that an overproduction of nitric oxide plays an important role in the pathogenesis of the hyperdynamic circulation exhibited by cirrhotic patients. Nevertheless, evidence is supported by studies performed in experimental models or by indirect measurements in humans. The purpose of this study has been to evaluate nitric oxide production in splanchnic vasculature of patients with cirrhosis and to investigate its possible relationship with systemic and splanchnic hemodynamics. METHODS: Nitric oxide synthase (NOS) activity was measured in hepatic artery and portal vein tissues of nine cirrhotic patients. Samples were obtained during liver transplantation. Control samples were obtained simultaneously from the corresponding tissues of the liver donors. Hemodynamic parameters were determined with Doppler ultrasonography. RESULTS: NOS activity was significantly higher in hepatic artery of cirrhotic patients than in controls (8.17 +/- 1.30 vs 4.57 +/- 0.61 pmoles/g of tissue/min, P < 0.05). Patients with ascites showed a higher hepatic artery NOS activity than patients without ascites. Highly significant correlation was observed between cardiac output and hepatic artery NOS activity as well as between portal blood flow and hepatic artery NOS activity. CONCLUSIONS: The present study demonstrates an enhanced production of nitric oxide in the splanchnic vasculature of patients with cirrhosis.     

Treatment of vascular complications following liver transplantation: multidisciplinary approach

BACKGROUND/AIMS: Complications affecting the vascularization of the graft following orthotopic liver transplantation still represent a significant cause of graft loss and patient mortality. Strategies have recently been developed for the early detection and treatment of these complications before irreversible graft failure takes place. METHODOLOGY: A series of 429 consecutive liver transplants performed on 384 patients between April 1986 and December 1998 was retrospectively reviewed to assess the incidence of all the vascular complications and the results of their treatment with either surgery or interventional radiology. RESULTS: The incidence of vascular complications was 6.06% for the hepatic artery, 2.56% for the inferior vena cava and 1.16% for the portal vein. As regards anastomotic stenosis and thrombosis, the requirement of retransplantation decreased progressively with the advent of systematic postoperative screening with duplex Doppler ultrasonography and the introduction of graft-salvage procedures, falling from 50% for those cases diagnosed before 1996 to 19% for those diagnosed from 1996 on. Mortality following 18 graft-salvage procedures was 11.1% versus 41.6% following retransplantation. Graft-salvage procedures were successful in 14 out of 18 cases. CONCLUSIONS: Close surveillance of the vascular anastomoses and multidisciplinary approach to the treatment of vascular complication after liver transplantation considerably reduces graft loss and patient mortality.