Branch Of Portal Vein Research Articles

Changes of intrahepatic lipid composition after portal vein embolization

Objective: Portal vein embolization is performed to prevent postoperative liver failure by enlarging the future remnant small liver. Since the liver is a main organ to organize lipid metabolism, lipid composition would be significantly changed in ipsilateral liver lobe after portal vein embolization. The purpose of this study is to examimne the change of intrahepatic lipid composition after portal vein embolization by mass spectrometry. Methods: As an animal model, the left portal vein branch was ligated under stereoscopic microscopy in 9–12 week old C57BL/6J mice. Liver samples were taken before and 6, 12, 24, 72 and 168 hr after surgery. Intrahepatic lipid change was evaluated with Oil red O staining and mass matrix assisted laser desorption/ ionization imaging mass spectrometry (MALDI-IMS). Results: The weight of non-PVL lobe (nPVLL) was significantly increased 72 hr after PVL. Oil red O staining showed the transient increase of triglyceride (TG) in nPVLL 24 hr after PVL. By MALDI-IMS analysis, the levels of phosphatidylcholine (PC), but not lysophosphatidylcholine (LPC), significantly increased in nPVLL 72 hr after PVL. As the results, the ratio of PC against LPC in nPVLL 72 hr after PVL was significantly higher than in PVLL. Conclusion: PVL induces the transient increase of PCs, major components of cellulart membrane, in future regenerating liver (non-PVL lobe). Such phospholipid increase would be necessary for increased turnover of cell membrane to gain the liver volume.

Anatomic Variations of the Right Portal Vein: Prevalence, Imaging Features, and Implications for Successful Transjugular Intrahepatic Portosystemic Shunt Creation.

Given the widespread use of transjugular intrahepatic portosystemic shunt (TIPS) creation for the treatment of portal hypertensive complications, a working knowledge of portal venous anatomy is critical for interventional radiologists. The right portal vein – which is most commonly accessed during TIPS – is subject to various anatomic variants that may potentially impact procedure success. This pictorial essay characterizes the anatomic patterns of the right portal vein branching in terms of type and frequency based on case series review. The work also explains the potential procedural implications of the right portal vein anatomic variations as they pertain to TIPS technical success.

Ozone oxidative intervention protects against hepatic ischemia reperfusion injury in rats

Objective To explore the protective effect of ozone oxidative preconditioning on hepatic ischemia reperfusion injury in rats. Methods Eighteen 8-week-old SPF Sprague-Dawley male rats weighting 250~300 g were randomly divided into three groups (n=6 each): sham operation group (group S), ischemia/reperfusion group (group I/R) and ozone oxidative preconditioning group (group O3+ I/R). In Group O3+ I/R, rats received five-day preconditioning treatments by intraperitoneal injection of ozone and oxygen mixed gases (ozone concentration 50 mg/L, 1 mg·kg-1·d-1), and then experienced the procedure of hepatic ischemia/reperfusion injury. Model of hepatic ischemia/reperfusion injury was established by clamping the branches of hepatic artery and portal vein in the median and left lateral hepatic lobes for 45 min, followed by 3-h reperfusion. After reperfusion, blood samples were taken from the aorta abdominalis for detecting serum aminotransferases (ALT & AST). These rats were executed and the hepatic tissue samples were collec-ted for measuring hepatic malondialdehyde (MDA) and superoxide dismutase (SOD) level. Results Compared with group S, concentrations of serum ALT, AST and hepatic MDA were increased in group I/R and O3+ I/R; concentrations of hepatic SOD were decreased (P<0.05) in group I/R, but concentration of hepatic SOD was increased in group O3+ I/R. Compared with group IR, concentrations of serum ALT, AST and hepatic MDA were decreased, while concentration of hepatic SOD was increased in group O3+ I/R (P<0.05). Conclusion Ozone oxidative preconditioning could inhibit the lipid peroxidation to protect the rats against hepatic ischemia/reperfusion injury. Key words: Ozone oxidative preconditioning; Ischemia/reperfusion injury; Liver

Incidence of postoperative hepatic encephalopathy in transjugular intrahepatic portosystemic shunt: a systematic review

Objective To explore the effect of puncture the left or right branch of portal vein on the incidence of postoperative hepatic encephalopathy in transjugular intrahepatic portosystemic shunt (TIPS). Methods A literature search was conducted through investigating PubMed, Cochrane Library, CNKI digital library and Wanfang databases. Randomized controlled trials and cohort studies related to the effect of puncture the left or right branch of portal vein on the incidence of postoperative hepatic encephalopathy in TIPS were included in this review. According to the methods for Cochrane systematic review, the data were extracted, the quality of the literatures was evaluated, statistical analysis was conducted and the data were analyzed with RevMan 5.0. Results One randomized controlled trial and four cohort studies, including 552 patients with liver cirrhosis received TIPS, were finally included in this review. Random-effects model meta-analysis showed that puncture of the left branch of portal vein in TIPS caused lower incidence of postoperative hepatic encephalopathy than puncture of the right branch of portal vein (RR=0.51, 95%CI was 0.39 to 0.66, P<0.01). Conclusion Puncture of the left branch of portal vein in TIPS can significantly reduce the incidence of postoperative hepatic encephalopathy in comparison with puncture of the right branch of portal vein. Key words: Hypertension, portal; Portasystemic shunt,transjugular intrahepatic; Hepatic encephalopathy; Incidence; Systematic review

A Tumor Localized in the Portal Vein

Question: A 56-year-old man underwent annual abdominal ultrasonography (US) as a medical checkup and a mass was found in his portal vein. Further examination was required and he was admitted to our hospital. He had no significant chief complaints, family history, or past medical history. On physical examination, no significant findings were revealed. Laboratory data were as follows: aspartate aminotransferase of 57 IU/L, alanine aminotransferase of 42 IU/L, lactate dehydrogenase of 302 IU/L, and γ-glutamyltransferase of 248 IU/L. Tumor markers were as follows: carcinoembryonic antigen of 4.7 ng/mL carbohydrate antigen 19-9 of 0.9 U/mL, alpha-fetoprotein of 8.6 U/mL, DUPAN-2 of 155 U/mL, neuron-specific enolase of 17.74 ng/mL, and protein induced by vitamin K absence-2 of 18 mAU/mL. Serologic tests for hepatitis B virus and hepatitis C virus were negative. Abdominal US demonstrated a mass occupying the portal vein near the head of the pancreas (Figure A). Doppler examination demonstrated no blood flow in the portal vein. Early phase-enhanced computed tomography (CT) showed a homogenously enhanced mass occupying the portal vein and it elongated to secondary branches of the right intrahepatic portal vein and the superior mesenteric vein (Figure B). On CT and endoscopic US (EUS) examinations, there were no other detectable lesions suggesting primary tumors in the pancreas, liver or other organs. Positron emission tomography (PET) CT disclosed high enhancement in portal vein identical to the mass lesion (Figure C). How do you diagnose the tumor? What is the most likely diagnosis? See the Gastroenterology web site (www.gastrojournal.org) for more information on submitting your favorite image to Clinical Challenges and Images in GI. To make a histologic diagnosis, we performed endoscopic ultrasound fine needle aspiration (Figure D). Microscopically, the tumor showed an alveolar growth pattern and cells were eosinophilic and some of them were amphophilic (Figure E). Immunohistochemical staining for both bcl-10 (Figure F) and trypsin (Figure G) was positive in the tumor. These microscopic features were consistent with acinar cell carcinoma of the pancreas. Because the tumor was invaded into secondary branches of both the right and left intrahepatic veins and the superior mesenteric vein, the tumor was considered to be unresectable. We started treating the tumor with chemotherapy. Acinar cell carcinoma is a rare malignant epithelial neoplasm and represents 1% to 2% of all exocrine pancreatic neoplasms.1Sun Y. Wasserman P.G. Acinar cell carcinoma arising in the stomach: a case report with literature review.Hum Pathol. 2004; 35: 263-265Crossref PubMed Scopus (41) Google Scholar We herein described an extremely rare case of pancreatic acinar cell carcinoma localized in the portal vein without any detectable primary lesions in the pancreas or other organs. In our patient, all the imaging studies including US, CT, PET-CT, and EUS could not detect any tumors in the pancreas. There are few case reports on pancreatic acinar cell carcinoma arising from non-pancreatic tissues, including the stomach,1Sun Y. Wasserman P.G. Acinar cell carcinoma arising in the stomach: a case report with literature review.Hum Pathol. 2004; 35: 263-265Crossref PubMed Scopus (41) Google Scholar the ampulla of Vater,2Kawakami H. Kuwatani M. Onodera M. et al.Primary acinar cell carcinoma of the ampulla of Vater.J Gastroenterol. 2007; 42: 694-697Crossref PubMed Scopus (10) Google Scholar and the jejunum.3Makhlouf H.R. Almeida J.L. Sobin L.H. Carcinoma in jejunal pancreatic heterotopia.Arch Pathol Lab Med. 1999; 123: 707-711Crossref PubMed Google Scholar In these cases, tumors were considered to arise from ectopic pancreatic tissue, because these tissues are derived from endoderm. However, in our patient, it is developmentally unlikely that acinar cell carcinoma arise from ectopic pancreatic tissue in the portal vein that is derived from mesoderm. Intraductal growth into the portal vein is also a rare feature for pancreatic acinar cell carcinoma. A few cases with portal tumor thrombus of acinar cell carcinoma have been reported. However, all of these cases had primary lesions in the pancreas and the tumor invaded directly to the portal vein. In conclusion, even though extremely rare, pancreatic acinar cell carcinoma should be included in the differential diagnosis of a tumor localized in the portal vein.

A propensity score analysis of two methods of hepatic vascular occlusion in hepatectomy

BackgroundThe key points in hepatectomy are reducing blood loss and preservation of hepatic function. The aim of this study was to compare the perioperative outcomes of partial hepatectomy using two techniques of hepatic vascular inflow occlusion. Materials and methodsA total of 1817 patients were selected from our multi-institutional hepatectomy database in China and classified into two groups: the hemihepatic inflow occlusion (HIO) group (n = 1693) and the ipsilateral portal vein branch occlusion (IPVBO) group (n = 124). Propensity score matching of patients in a ratio of 1:1 was conducted. The primary outcome was intraoperative blood loss. Secondary outcomes were postoperative liver function, postoperative morbidity and mortality, and duration of hospital stay after surgery. ResultsAfter propensity score matching, there were 124 patients in the IPVBO group and the HIO group, respectively. There were no significant differences between the two groups regarding intraoperative blood loss, blood transfusion requirement, operating time, postoperative morbidity and mortality, and duration of hospital stay after surgery (P > 0.05). However, The IPVBO group was associated with significantly lower peak in postoperative ALT level than the HIO group (P < 0.05). ConclusionsThe results indicated that IPVBO did not lead to more intraoperative blood loss compared with HIO, and it decreased the peak of postoperative ALT level. In terms of postoperative morbidity and mortality, duration of hospital stay after surgery, IPVBO was also equal to HIO. Thus, IPVBO could be an alternative method of hepatic inflow occlusion.

Transarterial chemoembolization (TACE) combined with sorafenib versus TACE for hepatocellular carcinoma with portal vein tumor thrombus: a systematic review and meta-analysis.

BackgroundThe benefits of transarterial chemoembolization plus sorafenib (TACE-S) in hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT) remain controversial. We compared the effectiveness and safety of TACE-S and TACE for HCC with PVTT.MethodsThe Cochrane Library, PubMed, EMBASE, Chinese National Knowledge Infrastructure, VIP, Wan Fang, and Sino Med databases were systematically searched for studies of HCC with PVTT treated using TACE-S. Two authors independently extracted study outcomes, including overall survival (OS), time to progression (TTP), objective response (tumor response) and adverse events (AEs).ResultsEight high-quality, retrospective studies with 1091 patients (TACE-S=356, TACE=735) were included in the review. Five retrospective studies with 973 patients (TACE-S=238, TACE=735) were included in the meta-analysis. The objective response rate (ORR, OR=3.59, 95% CI=1.74–7.39; I2=21%, P=0.0005) and disease control rate (DCR, OR=4.72, 95% CI=1.75–12.72; I2=56%, P=0.002) favored TACE-S. TACE-S significantly increased 6-month OS (OR=3.47; 95% CI=2.47–4.89; I2=0%, P < 0.00001) and 1-year OS (OR=3.10; 95% CI=2.22–4.33; I2=41%, P < 0.00001). The hazard ratio (HR) for OS (HR=0.62; 95% CI=0.51–0.75; I2=30%, P < 0.00001) also indicated that TACE-S was superior to TACE. TACE-S with PVTT had better outcomes in the first-order portal vein branch and lower-order portal vein branches than in the main portal vein and upper branches to superior mesenteric vein. The most common AEs were hand-foot skin reaction (HFSR, 178; 73%), diarrhea (142; 58%) and alopecia (76; 31%); AEs of grade 3/4 were rare.ConclusionsTACE-S may improve OS, ORR, TTP and DCR for HCC patients with PVTT compared to TACE.

Analysis of surgical treatment and prognostic factors for hepatocellular carcinoma with portal vein tumor thrombus

Background: Hepatocellular carcinoma (HCC) was the most common primary malignant liver tumor. The portal vein thrombosis (PVTT) of 10–40% were detected when HCC is exactly diagnosed. The patients whose PVTT existed in main branch of portal vein had poor prognosis. Whether hepatectomy could improve the survival rate of patients of HCC with PVTT was currently unknown. This study was to explore the prognosis and affecting factors of HCC with PVTT after liver resection.

Application value of three-dimensional visualization technology in the resectability assessment and surgical planning for huge hepatic carcinoma

Objective To investigate the application value of three-dimensional (3D) visualization technology in the resectability assessment and surgical planning for huge hepatic carcinoma. Methods The retrospective cross-sectional study was conducted. The clinical data of 48 patients with huge hepatic carcinoma who were admitted to the Zhujiang Hospital of Southern Medical University between January 2012 and June 2015 were collected. The preoperative image of computed tomography (CT) was converted to 3D reconstruction, visual observations and simulated surgery for assessing the tumor resectability through MI-3DVS, and corresponding treatments were performed according to the results of assessment. Observation indicators: (1) 3D reconstruction situations; (2) tumor resectability assessment through simulated surgery: tumor diameter, tumor volume, preoperative standard liver volume (SLV), tumor-free liver volume after simulated resection, future liver remnant (FLR) after simulated resection, hepatic resection rate (HRR); (3) surgical and postoperative situations: surgical procedures, resection extent, operation time, volume of intraoperative blood loss, complications, duration of postoperative hospital stay; (4) typical case analysis; (5) follow-up. Follow-up using outpatient examination and telephone interview was performed to detect the survival of patients and tumor recurrence or metastasis up to June 2016. Measurement data with normal distribution were represented as ±s. Results (1) Three-D reconstruction situations: 48 patients with huge hepatic carcinoma received successful 3D reconstruction and visual observations. Portal vein branches and hepatic vein branches reached level 4 through 3D reconstruction, and spacial position relationship between tumor and intrahepatic vascular backbones or branches can be clearly observed, as well as location and degree of vascular compression and invasion. (2) Tumor resectability assessment through simulated surgery: of 48 patients receiving simulated hepatectomy, 26 underwent hepatectomy and 22 didn′t undergo hepatectomy based on the assessment of resectability. Tumor diameter, tumor volume, preoperative SLV, tumor-free liver volume after simulated resection, FLR after simulated resection and HRR through assessment of 3D reconstruction and simulated surgery were (12.3±2.0)cm, (838±284)mL, (1 884±391)mL, (494±140)mL, (551±184)mL, 46%±12% in 26 patients with resectable tumor and (14.0±2.0)cm, (1 877±1 240)mL, (2 945±1 194)mL, (666±206)mL, (402±86)mL, 62%±9% in 22 patients with unresectable tumor, respectively. (3) Surgical and postoperative situations: 26 patients with resectable tumor underwent hepatectomy, without occurrence of death. Of 26 patients, 21 underwent anatomic hepatectomy, including 12 undergoing right hemihepatectomy, 3 undergoing left hemihepatectomy, 2 undergoing right lobectomy of the liver, 2 undergoing right posterior lobectomy of the liver, 1 undergoing left lobectomy of the liver and 1 undergoing resection of hepatic segment Ⅴ+ Ⅵ. And 5 underwent non-anatomic hepatectomy, including 2 with reduced right hemihepatectomy, 1 with resection of hepatic segment Ⅱ+ Ⅲ and partial segment Ⅳ, 1 with resection of hepatic segment Ⅵ + Ⅶ and partial segment Ⅴ and 1 with resection of hepatic segment Ⅴ+ Ⅵ and partial segment Ⅶ. Operation time and volume of intraoperative blood loss in 26 patients were respectively (6.4±1.3)hours and (712±633)mL. Three patients with postoperative pleural effusion and 1 with postoperative bile leakage were cured by symptomatic treatment, without the occurrence of hepatic dysfunction. Duration of postoperative hospital stay was (19±8)days. Of 22 patients with unresectable tumor, 14 underwent transcatheter hepatic arterial chemoembolization (TACE), 4 underwent portal vein ligation, 1 underwent portal vein embolization and 3 abandoned treatment. (4) Typical case analysis: results of 3D reconstruction through MI-3DVS showed that patients underwent portal vein right anterior branch-preserving expanded right posterior lobectomy of the liver, with a smooth recovery. Patients were followed up for 14.0 months, with a good survival and without tumor recurrence and metastasis. (5) Follow-up: 40 of 48 patients were followed up for 6.0-33.0 months with a median time of 13.0 months, including 26 with surgery and 14 without surgery. During the follow-up, the median survival time of patients with and without surgery was 20.0 months and 10.5 months, respectively. Twelve patients with surgery had tumor recurrence and metastasis. Conclusion Three-dimensional visualization technology is safe and feasible in the resectability assessment and surgical planning for huge hepatic carcinoma, and it will benefit to reduce risk of surgery. Key words: Hepatic neoplasms, huge; Hepatectomy; Three-dimensional visualization

Risk Factors of Liver Dysfunction Induced by Microwave Ablation in Patients with Hepatocellular Carcinoma

To investigate the risk factors of the aggravation of liver function induced by microwave ablation (MWA) of patients with hepatocellular carcinoma (HCC). We retrospectively reviewed the liver function of 498 patients with HCC undergoing MWA treatment. The dynamic changes of liver enzymes and Child-Pugh scores were observed. The potential risk factors, including the relative position between the tumor and portal vein (PV), tumor numbers, ablation volumes, Child-Pugh classifications, platelet, APRI and MELD scores, were analyzed. Based on the relative position between the tumor and PV, the tumors of the patients were divided into four groups, (1) far away from PV; (2) close to the third branch of PV (< 5mm); (3) close to the second branch of PV (< 5mm); (4) close to the first branch of PV (< 5mm). Complete response was achieved in 409 (98.08%) of 417 patients with tumors far away from the PV and in 89 (95.70%) of 93 patients with tumors close to a branch of the PV. Large fluctuations in the levels of ALB, ALT, AST and TBIL were observed three days after treatment, while the concentrations of ALP and γ-GGT were relative stable. 13.86% (69/498) patients suffered from liver function damage, that is, having an increase of Child-Pugh score by two three days after MWA. The incidences of liver dysfunction of the patients with tumors close to PV, more than three tumors, ablation volumes lager than or equal to 22.5 cm3, Child-Pugh classification B, APRI > 1.6, MELD > 30 or PLT < 110 × 109/L were 53.85%, 46.15%, 20.60%, 24.24%, 31.53%, 22.55% or 18.92%, respectively, much higher than those of patients without above characteristics. MWA can cause a transient deterioration of liver function. Patients with tumors close to PV, large numbers of tumors or large ablation volumes may present a great fluctuation of liver enzymes and an aggravation of liver dysfunction. In addition, poor liver reserve function is a risk factor of liver function damage but not the elevations of liver enzymes after MWA.

Efficacy and Safety of Direct-Acting Oral Anticoagulants Use in Acute Portal Vein Thrombosis Unrelated to Cirrhosis

In acute portal vein thrombosis (APVT) unrelated to cirrhosis, anticoagulant therapy is classically started with low molecular weight heparin or vitamin K antagonists. New direct-acting oral anticoagulants (DOACs) are used in the treatment of venous thrombosis outside the splanchnic vascular bed, but not in the latter. We report a young female with APVT occurring in a non-cirrhotic liver linked to heterozygosity of factor V-Leiden and prothrombin G20210A gene mutations. Rivaroxaban was started, with total recanalization of the left and partial recanalization of the right portal vein branches, without complications. New DOACs do not need daily subcutaneous injections nor routinely blood coagulation control tests, making its use attractive, eventually increasing patient’s compliance. If proved to be safe and effective in the future studies, its use may be extended to PVT treatment. This case shows that rivaroxaban was safe, not only prevented the extension of thrombosis in the portal tract, but also resolved PVT, at least partially.

An Efficient and Clinical-Oriented 3D Liver Segmentation Method

By segmenting, modeling, and visualizing computed tomography sequence data, surgeons can better understand the spatial relationship of the intrahepatic vein, portal vein, artery, and tumor. Accurate preoperative understanding of liver anatomy and volume of the corresponding liver segment are necessary for anatomical liver resection. This paper gives an efficient and semiautomatic method for segmenting the liver in clinical cases. This method is based on Couinaud’s theory and automatically divides the liver segment by portal vein branches. Considering the vascular variation of individual cases, the adjustment of the portal vein branches was provided on the basis of automatic segmentation, thus adaptability to various cases was implemented. For the final segmentation results, the portal vein blood supply of different liver segments can be confirmed by 3-D visualization, and the liver volume can be accurately estimated. Experiments show that this liver segmentation method has good clinical value.

Extrahepatic Portal Vein Obstruction in Children: Role of Preoperative Imaging.

Aim:Extrahepatic portal vein obstruction (EHPVO) is characterized by features of recent thrombosis or portal hypertension with portal cavernoma as a sequel of portal vein obstruction. Imaging of spleno-portal axis is the mainstay for the diagnosis of EHPVO. The aim of this study is to analyze the role of imaging in the preoperative assessment of the portal venous system in children with EHPVO.Materials and Methods:A hospital-based cross-sectional study was conducted on twenty children with EHPVO aged between 1 and 18 years over a period of 1 year. The children were evaluated clinically, followed by upper gastrointestinal endoscopy. Radiological assessment included imaging of the main portal vein, its right and left branches, splenic vein, and superior mesenteric vein using color Doppler ultrasonography (CDUSG) and magnetic resonance portovenogram (MRP). Evidence of portal biliopathy, status of collaterals, and possible sites for portosystemic shunt surgery were also examined.Results:All the patients presented in chronic stage with portal cavernoma and only one patient (5%) had bland thrombus associated with cavernoma. The CDUSG and MRPs had a sensitivity of 66.6-90% and 96.7% and specificity of 91.5% and 98.3% respectively with regard to the assessment of the extent of thrombus formation and flow in the portal venous system. Both the modalities were found to be complementary to each other in preoperative assessment of EHPVO. However, the sensitivity of MRP was slightly superior to CDUSG in detecting occlusion and identifying portosystemic collaterals and dilated intrahepatic biliary radicals.Conclusion:Results of the present study indicate that MRP is well suited and superior to CDUSG in the preoperative imaging of patients with EHPVO.

Pregnancy Complicated by Portal Hypertension Secondary to Noncirrhotic Portal Fibrosis

ABSTRACT Noncirrhotic portal fibrosis (NCPF) is a liver disorder characterized by periportal fibrosis of small and medium branches of portal vein resulting in portal hypertension with the sequelae of variceal bleed requiring immediate attention. We report a case of 27-years-old primigravida with NCPF presented for her booking visit with 3 months of amenorrhea. Clinical examination and ultrasound revealed 12 weeks of intrauterine gestation with moderate splenomegaly, dilated portal vein, and splenic vein. The patient was referred to medical gastroenterologist. Hematological investigations were found normal except for borderline thrombocytopenia. Upper gastrointestinal endoscopy revealed grade I esophageal varices. She was monitored bimonthly by obstetrician and hepatologist as she was potential for variceal bleed, anemia, liver derangement, and coagulation abnormalities during antenatal and intrapartum period. She had well-preserved liver function throughout pregnancy and no variceal bleed. Fetal surveillance was done and she received prophylactic corticosteroids at 28 weeks of gestation for fetal lung maturation. Antenatal period was uneventful. In view of breech presentation, elective cesarean section was performed and a healthy male baby was delivered weighing 2.9 kg, with good Apgar score. Intrapartum and postpartum period was uneventful. Surveillance by a multidisciplinary team is important for such high-risk pregnancy for optimizing obstetric and neonatal care. How to cite this article Niroopama P. Pregnancy Complicated by Portal Hypertension Secondary to Noncirrhotic Portal Fibrosis. J South Asian Feder Obst Gynae 2017;9(1):63-65.

Effect of initial stent position on patency of transjugular intrahepatic portosystemic shunt.

AIMTo evaluate the effect of initial stent position on transjugular intrahepatic portosystemic shunt (TIPS).METHODSWe studied 425 patients from January 2004 to January 2015 with refractory ascites or variceal bleeding who required TIPS placement. Patients were randomly divided into group A (stent in hepatic vein, n = 57), group B (stent extended to junction of hepatic vein and inferior vena cava, n = 136), group C (stent in left branch of portal vein, n = 83) and group D (stent in main portal vein, n = 149). Primary unassisted patency was compared using Kaplan-Meier analysis, and incidence of recurrence of bleeding, ascites and hepatic encephalopathy (HE) were analyzed.RESULTSThe mean primary unassisted patency rate in group B tended to be higher than in group A at 3, 6 and 12 mo (P = 0.001, 0.000 and 0.005), and in group D it tended to be lower than in group C at 3, 6 and 12 mo (P = 0.012, 0.000 and 0.028). The median shunt primary patency time for group A was shorter than for group B (5.2 mo vs 9.1 mo, 95%CI: 4.3-5.6, P = 0.013, log-rank test), while for group C it was longer than for group D (8.3 mo vs 6.9 mo, 95%CI: 6.3-7.6, P = 0.025, log-rank test). Recurrence of bleeding and ascites in group A was higher than in group B at 3 mo (P = 0.014 and 0.020), 6 mo (P = 0.014 and 0.019) and 12 mo (P = 0.024 and 0.034. Recurrence in group D was higher than in group C at 3 mo (P = 0.035 and 0.035), 6 mo (P = 0.038 and 0.022) and 12 mo (P = 0.017 and 0.009). The incidence of HE was not significantly different among any of the groups (P = 0.965).CONCLUSIONThe initial stent position can markedly affect stent patency, which potentially influences the risk of recurrent symptoms associated with shunt stenosis or occlusion.

Techniques of Linear Endoscopic Ultrasound in the Evaluation of Portal Vein Branches

The main portal vein bifurcation occurs near the liver hilum. Both the branches travel in the transverse fissure of liver. The bifurcation lies in an imaginary transverse plane in the transverse fissure, in which the left portal vein is at a higher level than the right portal vein and the left portal vein has a longer extrahepatic course (~2/3rd of transverse fissure) as compared to the right portal vein (~1/3rd of transverse fissure). The right portal vein divides into two branches after entering the liver. The imaging of portal vein branches can be done from three stations: abdominal part of esophagus and stomach, duodenal bulb, and descending duodenum. The imaging of portal vein branches is significantly aided by following the fissures of liver. The imaging from stomach keeps the focus of imaging around the left sagittal fissure, where the left portal vein is present; the imaging from duodenal bulb keeps the focus of imaging around the transverse fissure, where the main portal vein is present; and the imaging from descending duodenum keeps the focus of imaging around the right sagittal fissure, where the right portal vein is present. Following the fissure from one part to other is possible by clockwise and counterclockwise rotation and allows the imaging of different parts of portal vein. The imaging from the abdominal part of esophagus and stomach is the most convenient station of imaging for most operators.

Human liver regeneration in advanced cirrhosis is organized by the portal tree

In advanced cirrhosis new hepatocytic nodules are generated by budding of ductules in areas of parenchymal extinction. However, the vascular alterations in the areas of parenchymal extinction, the blood supply and the structure of the new hepatocytic nodules have not been analyzed in detail. Explanted human cirrhotic livers of three different etiologies and two experimental rat models of cirrhosis were thoroughly examined. 3D reconstruction of the immunohistochemically stained serial sections and casting of human and experimental cirrhotic livers have been used to reveal the structural organization of the regenerative buds. In areas of parenchymal extinction the skeleton of the liver, the portal tree is preserved. The developing regenerative nodules are positioned along the portal tree and are directly supplied by terminal portal venules. The expanding nodules grow along the trunks of the portal vein. Casting of human and experimental cirrhotic livers by colored resin confirms that nodules are supplied by portal blood. The two other members of the portal triads become separated from the portal veins. As the structure of the hepatocyte nodules (centrally located portal vein branches, bile ducts at the periphery, hepatic veins and arteries in the connective tissue) impedes the restoration of normal liver structure, the basic architecture of hepatic tissue suffers permanent damage. We suggest that "budding" may initiate the second, irreversible stage of cirrhosis. Cirrhosis is the final common outcome of long lasting hepatic injury defined as the destruction of the normal liver architecture by scar tissue. In the late phase of cirrhosis stem cells-derived hepatocyte nodules appear along the branches of the portal vein suggesting an important role of this specially composed blood vessels (containing digestive end-products from the stomach and intestines) in liver regeneration. Our results contribute to a better understanding of this serious liver disease.

Rabbit model provides new insights in liver regeneration after transection with portal vein ligation

BackgroundThe rabbit model of associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) has not been reported before. Materials and methodsNew Zealand white rabbits were allocated to two protocols. Protocol 1 involved either liver parenchymal transection (LPT, n = 5) or portal vein ligation (PVL, n = 5). Protocol 2 involved the ligation of different portal vein branches combined with liver partition, including the LPT + 20% PVL group (n = 5; the caudate portal vein was ligated), the LPT + 50% PVL group (n = 5; the left portal vein was ligated), and the LPT + 70% PVL group (n = 10; both veins were ligated). Computed tomography liver volumetry was performed immediately after operation. Blood samples were harvested before surgery and at days 1, 3, 7, or 14 after surgery for liver function evaluation. Most rabbits were humanely euthanized on day 7. The livers were harvested, divided into lobes, and weighed; biopsies of each lobe and immunohistochemical staining were performed. ResultsIn this article, we present a new rabbit model to simulate ALPPS procedure, with a description of the regional anatomical features, surgical routes, and key techniques. The growth rate of remnant right lobe volume increased with proportionally PVL combined with LPT. Specifically, right lobe volume growth rate of the LPT + 50% PVL group overwhelmed 70% PVL alone. ConclusionsThere were putative underlying mechanisms other than portal inflow redistribution in triggering residual liver regeneration after ALPPS procedure. This rabbit model is feasible for further mechanism research of this special clinical phenomenon.

Portal supply of segment IV of the liver based on CT-scan.

The portal vascularization of segment IV (S4) of the liver has not been well described. Knowledge of the portal supply to S4 is of great interest for liver surgery and for interventional radiological procedures. This study aimed to analyse the distribution of portal vein branches supplying S4. We retrospectively analysed data from patients operated on for liver tumours between 2007 and 2016. Patients with involvement of S4 branches or the left portal vein, previous liver surgery or poor quality imaging were excluded. Branches originating from the right portal vein and/or from the transverse part of the left portal vein (TPLPV) and/or from the umbilical part of the portal vein (UPLPV) were identified. In 102 patients who underwent a right hepatectomy, S4 was vascularized by 2-8 branches of the left portal vein, with 84.3% of patients having 3-6 branches. Only eleven patients (10.8%) had portal branches originating from the TPLPV, with no impact on the number of branches coming from the UPLPV. Three patients (2.9%) had one branch from the right portal vein. In patients with only two or three branches supplying S4, the branches had a larger diameter and typically arose from a short common trunk which divided further within its first centimetres. Portal vascularization of S4 varies widely (2-8 branches) between patients and originates predominantly from the junction between the left portal vein and the round ligament. There is no anatomical rationale to divide S4 into S4a and S4b.

Incidence and clinical presentation of portal vein thrombosis in cirrhotic patients

Portal vein thrombosis (PVT) is due to many risk factors, but its pathogenesis is still not clearly understood. To identify the risk factors for PVT, we analyzed the clinical characteristics and complications associated with PVT in cirrhotic patients. We studied patients with liver cirrhosis who were admitted to our unit from April 2009 to December 2014. The patients were divided into the PVT and non-PVT groups, and were compared by variables including gender, age, the etiology of cirrhosis, stage of cirrhosis, complications, imaging, and treatment. PVT was found in 45 (9.8%) of 461 cirrhotic patients admitted to our hospital. Most patients (45.9%) had hepatitis B virus (HBV)-related cirrhosis, with a similar distribution of etiologies between the groups. However, there was no positive relationship between PVT and etiologies of cirrhosis. Most patients (71.5%) were in the stage of hepatic decompensation. No statistically significant differences were found in complications including esophageal varices, ascites, and hepatic encephalopathy between the groups. However, there was a significant positive correlation between hepatocellular carcinoma (HCC) and PVT (P<0.01). In 30 patients with PVT, thrombosis occurred in the portal vein and/or portal branches, 37.8% were diagnosed on ultrasound. The incidence of PVT was 9.8%, mainly in patients with HBV-related cirrhosis. The development of PVT was associated with the severity of liver disease and HCC.