Normal Hepatic Artery Research Articles

Retrospective Analysis of Aberrant Hepatic Artery in 1250 Patients with Hepatocellular Carcinoma Undergoing Transarterial Chemoembolization.

Aberrant hepatic artery is particularly common, and its diversity and complexity play a critical role in surgery. The aim of this study was to describe the incidence and type of aberrant hepatic artery, and to compare differences in transarterial chemoembolization (TACE) in patients with hepatocellular carcinoma (HCC) with vs without aberrant hepatic artery. This was a retrospective study of patients with HCC who received TACE at the same intervention center between March 15, 2020 and December 31, 2022. All patients who met inclusion criteria were divided into two groups based on whether or not they had aberrant hepatic artery. The aberrant hepatic artery was systematically classified according to variations in origin. We compared differences in baseline characteristics, operation duration, and postoperative hospitalization between the two groups. Postoperative adverse events and laboratory data were also compared. A total of 1250 patients hospitalized with HCC were included in the study (mean age, 58 ± 10 years, 1019 [81.5%] males). A high incidence of aberrant hepatic artery was found during TACE (21.3%, 266 of 1250), mainly involving a single variation of the aberrant left hepatic artery (aLHA) (6.1%, 76 of 1250) or aberrant right hepatic artery (aRHA) (10.9%, 136 of 1250) origin, as well as complex variations of the aLHA and aRHA origin (2.4%, 30 of 1250). When comparing patients with vs without aberrant hepatic artery, the TACE operation duration was significantly different (p < 0.001), and tended to be greater for patients with aberrant hepatic artery. In addition, differences between aberrant and normal hepatic artery groups in postoperative nausea and vomiting were statistically significant (40.2% vs 30.8%, respectively, p = 0.004). Postoperative laboratory examinations revealed significant differences in aspartate aminotransferase, alanine aminotransferase, and neutrophil percentage between the two groups (p < 0.05). The incidence of aberrant hepatic artery is extremely high, and the condition is characterized by complex variations. Moreover, aberrant hepatic artery may have a critical impact on the course of TACE treatment.

Microsurgical replacement of the right hepatic artery with the donor superior mesenteric artery in cadaveric donor pediatric liver transplantation.

To present our experience of using the pediatric donor superior mesenteric artery (SMA) as the interpositioning vessel to reconstruct the hepatic artery in pediatric deceased donor liver transplantation. Pediatric patients who received pediatric deceased donor livers from December 2019 to June 2021 were enrolled. A total of 43 pediatric recipients received pediatric deceased donor livers during the study period. Thirty-four (79.1%) pediatric donors had normal hepatic artery anatomy, while nine (20.9%) showed variant anatomies. The SMAs of the pediatric donors were interposed in the latter eight cases. The anastomosis between the donor distal SMA and the donor celiac trunk artery (CTA) was initially performed in the back-table period, after which the other anastomosis between the donor proximal SMA and recipient CHA was performed. Only one case showed HAT occurrence (incidence rate, 2.3%). However, no arterial complications occurred in pediatric recipients with donor grafts that showed the variation of RHA replacement from the SMA and had undergone usage of the donor's SMA as an interpositioning vessel. In pediatric deceased donor liver transplantation, the use of SMA as an interpositioning medium can solve the problems related to a tiny caliber and anatomical variations of the donor hepatic artery.

Prevalence of hepatic vascular anomalies in consecutive contrast-enhanced computed tomography images — a retrospective observational study

BackgroundLiver is a complex, highly vascular organ, where anatomical variations are the norm. This study aimed to analyze all the three hepatic vascular anatomical variations in a single study which would help us understand the prevalence of hepatic vascular (arterial, portal, venous) anomalies in the population catered to by our institution.MethodsA retrospective analysis of 545 contrast-enhanced CT scans was done from November 2019 from the institute PACS after satisfying the inclusion and exclusion criteria. The raw imaging data were processed in PACS software — Centricity™ Universal Viewer and Syngo.via Vb20 platform, for axial, coronal, and axial-oblique multiplanar reformation, maximum intensity projection (MIP), and volume rendering (VR) images. Data were analyzed in the three vascular phases to determine the anatomical variations. Analysis was done by two surgical residents in the division of HPB surgery, which was verified by a certified radiologist.ResultsThere were no major differences in the prevalence rates of the vascular anomalies across gender and domicile distributions. The prevalence of normal hepatic artery and variant hepatic artery in our study was 69% and 31%, respectively. Accessory left hepatic artery (10%) was the most common hepatic artery variant in our study. Single RHV was seen in 77.4%, and other RHV variants like two RHV with common trunk, two RHV with independent drainage, and three RHV with common trunk contribute 22.6% of our study population. Accessory inferior RHV was seen in 19.8% of the study population. Normal portal vein anatomy was found in 81.1% in our study, and the most common variant in our study population was trifurcation of portal vein (16.1%).ConclusionThis was the largest study until date from South India, studying all three hepatic vascular anatomical variations in a single study. Variations in the anatomy of hepatic arteries, portal veins, and hepatic veins are common. A good knowledge of the same is necessary especially for a hepatobiliary surgeon or for an interventional radiologist, to plan and avoid complications during a procedure. Preoperative contrast-enhanced CT scan and whenever necessary a VR or a MIP reconstruction will precisely help in identifying these variations.

Hepatic Artery Anomalies and Its Impact in Patients Undergoing Pancreaticoduodenectmy. A Comparative Study from Kashmir Valley

Background: Pancreaticoduodenectomy provides the only opportunity to cure resectable and borderline pancreatic ductal adenocarcinoma. This is linked to a high rate of morbidity and mortality, especially when combined with hepatic artery anomalies. The goal of this study was to analyse the spectrum and impact of hepatic artery anomalies on intraoperative and postoperative variables, and oncologic outcomes in patients undergoing pancreaticoduodenectomy. Materials and Methods: All patients with resectable periampullary or pancreatic head tumours who underwent pancreaticoduodenectmy (PD) were included. Patients were divided into two groups using computer-generated random numbers; Group A included patients who had pancreaticoduodenectmy (PD) with normal hepatic artery anatomy and Group B included patients with aberrant hepatic artery anatomy. The data was collected and analysed using SPSS 22. Results: Among the 238 patients who met the inclusion criteria, 177(74.36%) participants were included in Group A (Normal hepatic artery anatomy) and 61 (25.36%) in Group B (Aberrant hepatic artery anatomy). The mean age of patients in Group A was 51.3 ± 8.63 years while it was 50.6 ± 8.09 years in Group B. The difference in gender, BMI, pre-operative haemoglobin, bilirubin and albumin between two groups was statistically insignificant (P value &gt;0.05). The difference in mean operative time of Group A 230.9(168–390) minutes and Group B 319.6(200–620) minutes was statistically significant (p-value &lt;0.001). The mean blood loss in Group A (511.5 120.18 ml) was significantly lower than in Group B (623.6 127.06 ml) (P ≤ 0.001). There were no significant differences between the two groups in terms of post-operative pancreatic fistula, delayed gastric emptying, wound infection, atelectasis, hospital stay, peri-operative mortality, positive resection margins, and mean lymph node yield. Conclusion: Patients with hepatic artery anomalies who undergo pancreaticoduodenectomy have significantly more operative blood loss. This could be due to the procedure’s complexity and lengthy operative time. There were no differences between the two groups in terms of postoperative morbidity, oncological outcome, or mortality.

Impact of the aberrant right hepatic artery on local recurrence of pancreatic ductal adenocarcinoma after pancreaticoduodenectomy

BackgroundThe influence and risk associated with an aberrant right hepatic artery, a common anatomical variation, during pancreatoduodenectomy for pancreatic ductal adenocarcinoma has not been fully investigated. The present study analyzed the impact of an aberrant right hepatic artery on local recurrence after pancreatoduodenectomy for pancreatic ductal adenocarcinoma. MethodsA total of 169 patients with pancreatic ductal adenocarcinoma who underwent pancreatoduodenectomy at 2 separate Japanese medical institutions were retrospectively analyzed. ResultsThirty of 169 patients (17.7%) presented with an aberrant right hepatic artery. The incidence of local recurrence was higher in the aberrant right hepatic artery group than in the normal right hepatic artery group (43.3 vs 21.5%, P = .017). The local recurrence-free survival was significantly poorer in the aberrant right hepatic artery group than in the normal right hepatic artery group (P = .011). A multivariate analysis found that the aberrant right hepatic artery was an independent risk factor for local recurrence (hazard ratio: 3.74, P = .017). In the aberrant right hepatic artery group, more frequent local recurrence was observed in patients with tumors situated ≤10 mm from the aberrant right hepatic artery root. However, local recurrence was not observed in 2 out of 3 patients with tumors ≤10 mm from the aberrant right hepatic artery root who underwent pancreatoduodenectomy with combined resection of the aberrant right hepatic artery. ConclusionThe presence of an aberrant right hepatic artery in patients undergoing pancreatoduodenectomy for pancreatic ductal adenocarcinoma may be associated with an increased risk of postoperative local recurrence. Combined resection of the aberrant right hepatic artery may reduce local recurrence, especially for tumors near the root of the aberrant right hepatic artery.

Hepatic Artery and Portal Vein Variations using Contrast Enhanced Computed Tomography Abdominal Angiography

Introduction: Normal hepatic vascular anatomy and its variants carry considerable importance during liver transplants, laparoscopic surgeries, penetrating abdominal trauma, and radiological abdominal interventions. The occurrence of iatrogenic hepatic vascular injury increases in case of atypical anatomy and variations. Aim: To determine the prevalence of common hepatic artery and portal vein variants by using Multidetector Computed Tomography (MDCT). Materials and Methods: This is a hospital based retrospective study done in Sri Mankula Vinayagar Medical College and Hospital, Puducherry, India, between July 2019 and July 2020. The Contrast Enhanced Computed Tomography (CECT) abdominal angiography of 350 patients was taken for the study. The MDCT abdominal angiography was performed using 16 slice PHILIPS MX16 CT scanner with intravenous administration of non ionic iodinated contrast, having iodine content of 300 mg/mL at the dosage of 1.5 mL/kg body weight, using automated pressure injector at a rate of 3.5 mL/sec. Arterial phase and portal venous phase images were obtained at 25 and 55 seconds respectively. The hepatic artery anatomical types were classified according to Michel's classification and the portal vein according to Covey AM et al., classification. Data obtained was entered in EPI INFO version 7.2.1.0 and analysed using Statistical Package for the Social Sciences (SPSS) software version 24.0. Results: Hepatic artery proper (right and left hepatic arteries arising from common hepatic artery) (Type I) was seen in 222 (63.4%) of cases. The most common variant was replaced Left Hepatic Artery (LHA) from the left gastric artery (Type II) with a prevalence of 46 (13.1%). A normal portal vein branching pattern (Type I) was seen in 201 (57.4%) of cases. The most common variation was trifurcation (Type II) with a prevalence of 68 (19.4%). Conclusion: Knowledge about normal hepatic artery, portal vein, and its variants is important in hepatic interventions and CT angiography is the modality of choice for evaluating the vascular anatomy.

Anatomic Variations of the Hepatic Artery in 5625 Patients.

To analyze the origin and anatomic course of the hepatic arteries by using digital subtraction angiography (DSA) and multidetector CT in a large study sample. This retrospective study included 5625 patients who underwent liver CT and chemoembolization between January 2005 and December 2018 (mean age, 60 years ± 11 [range, 11-99 years]; 4464 males). The CT and DSA images were reviewed to evaluate the visceral arterial anatomy for variations in the celiac axis and hepatic arteries. Aberrant right hepatic arteries (aRHAs) and aberrant left hepatic arteries (aLHAs) were defined on the basis of their origin and anatomic course. Statistical analyses were performed to evaluate the association between aRHAs and aLHAs and the association between variations in the hepatic artery and celiac axis. Right hepatic arteries were categorized as being aRHAs (if originating from the proximal to middle common hepatic artery, gastroduodenal artery, superior mesenteric artery [SMA], celiac axis, aorta, splenic artery, or left gastric artery [LGA]) or as being aLHAs (if arising from the LGA, celiac axis, aorta, or SMA). The prevalence of aRHAs (15.63%; 879 of 5625) and the prevalence aLHAs (16.32%; 918 of 5625) were similar. Patients with an aRHA were more likely to have an aLHA than those without an aRHA (29.01% vs 13.97%; P < .001), and patients with an aLHA were more likely to have an aRHA than those without an aLHA (27.78% vs 13.26%; P < .001). There was no association between the hepatic arterial variations and celiac axis variations. A hypothetical anatomic model summarizing the observed variations was created. A comprehensive list of hepatic arterial variations and a three-dimensional hypothetical model for the observed variations were described.Keywords: CT, Angiography, Liver, Anatomy, Arteries© RSNA, 2021 Supplemental material is available for this article. See also commentary by Sutphin and Kalva in this issue.

Ultrasound shear wave elastography: does it add value to gray-scale ultrasound imaging in differentiating biliary atresia from other causes of neonatal jaundice?

Neonatal/infantile jaundice is relatively common, and most cases resolve spontaneously. However, in the setting of unresolved neonatal cholestasis, a prompt and accurate assessment for biliary atresia is vital to prevent poor outcomes. To determine whether shear wave elastography (SWE) alone or combined with gray-scale imaging improves the diagnostic performance of US in discriminating biliary atresia from other causes of neonatal jaundice over that of gray-scale imaging alone. Infants referred for cholestatic jaundice were assessed with SWE and gray-scale US. On gray-scale US, two radiology readers assessed liver heterogeneity, presence of the triangular cord sign, hepatic artery size, presence/absence of common bile duct and gallbladder, and gallbladder shape; associated interobserver correlation coefficients (ICC) were calculated. SWE speeds were performed on a Siemens S3000 using 6C2 and 9L4 transducers with both point and two-dimensional (2-D) SWE US. Both univariable and multivariable analyses were performed, as were receiver operating characteristic curves (ROC) and statistical significance tests (chi-squared, analysis of variance, t-test and Wilcoxon rank sum) when appropriate. There were 212 infants with biliary atresia and 106 without biliary atresia. The median shear wave speed (SWS) for biliary atresia cases was significantly higher (P<0.001) than for non-biliary-atresia cases for all acquisition modes. For reference, the median L9 point SWS was 2.1m/s (interquartile range [IQR] 1.7-2.4m/s) in infants with biliary atresia and 1.5m/s (IQR 1.3-1.9m/s) in infants without biliary atresia (P<0.001). All gray-scale US findings were significantly different between biliary-atresia and non-biliary-atresia cohorts (P<0.001), intraclass correlation coefficient (ICC) range 0.7-1.0. Triangular cord sign was most predictive of biliary atresia independent of other gray-scale findings or SWS - 96% specific and 88% sensitive. Multistep univariable/multivariable analysis of both gray-scale findings and SWE resulted in three groups being predictive of biliary atresia likelihood. Abnormal common bile duct/gallbladder and enlarged hepatic artery were highly predictive of biliary atresia independent of SWS (100% for girls and 95-100% for boys). Presence of both the common bile duct and the gallbladder along with a normal hepatic artery usually excluded biliary atresia independent of SWS. Other gray-scale combinations were equivocal, and including SWE improved discrimination between biliary-atresia and non-biliary-atresia cases. Shear wave elastography independent of gray-scale US significantly differentiated biliary-atresia from non-biliary-atresia cases. However, gray-scale findings were more predictive of biliary atresia than elastography. SWE was useful for differentiating biliary-atresia from non-biliary-atresia cases in the setting of equivocal gray-scale findings.

S2577 Management of Splenic Artery Steal Syndrome Following Liver Transplantation by Splenic Artery Embolization

INTRODUCTION: The following case series analyzes patients that received a splenic artery embolization (SAE) following an orthotopic liver transplant (OLT). SAE following OLT is performed to correct splenic artery steal syndrome (SASS), where the splenic artery experiences an increase in blood flow at the expense of the hepatic artery. Normal hepatic artery blood flow is needed to ensure a successful transplant. CASE DESCRIPTION/METHODS: Four patients presented for OLT; three with living donors and one standard donor. The indications for OLT were alcoholic cirrhosis, cryptogenic cirrhosis with pancytopenia, NASH, and primary sclerosing cholangitis. The average MELD scores were 18 [11-26]. Two patients had previous history of CT diagnosed thrombosis in the right hepatic and portal veins. One patient had an intraoperative portal vein thrombectomy. Three patients had good size matched anastomotic connections for the hepatic arteries, while one patient’s recipient arteries were smaller than the donors. Upon post-transplant ultrasound, each patient had an increased hepatic artery resistivity index (RI) in the proximal, middle and distal parts of the artery. This indicates decreased blood flow to the liver as part of SASS. The relevant laboratory values immediately preceding SAE showed an average AST of 171.5 [45-301], ALT of 378.25 [249-458], alkaline phosphate of 176.75 [46-368], total bilirubin of 3.9 [1.9-6.6], direct bilirubin of 2.6 [1.4-4.4], and creatinine of 0.9 [0.73-1.05]. To correct this, all patients received an SAE on average 96.5 hours [20-213] following OLT to re-establish adequate blood flow to the liver. This is confirmed through a follow up ultrasound, which reveals decreased hepatic artery RI in all patients. The patient with primary sclerosing cholangitis received a re-do hepatojujenoctomy, however the other three patients did not have any strictures based on MRCP. None of the patients had graft rejection and are currently 6 months to 1 year post-transplant. DISCUSSION: SAE following OLT serves as a viable option for treating SASS. This procedure re-stored proper blood flow through the hepatic artery to the transplanted liver, which prevents graft rejection.

S2453 Nice to Meat Your New Liver: A Unique Case of Hepatitis E

INTRODUCTION: Hepatitis E virus (HEV) infection in immunosuppressed patients carries high mortality if left untreated. HEV is primarily a hepatotropic virus but can affect the central nervous system, peripheral nervous system, renal system and hematologic system. Immunosuppressed patients who fail to clear the virus can develop chronic hepatitis if infected with HEV genotype 3 or 4, requiring treatment. We report a patient with HEV infection shortly after orthotopic liver transplantation. CASE DESCRIPTION/METHODS: A 48-year-old gentleman presented to the clinic with generalized weakness and fatigue for 1-month associated with myalgia that worsened by the end of the day. He underwent orthotopic liver transplant due to end-stage-liver disease from alcohol 4 months before current presentation and was maintained on triple therapy immunosuppression. Initial exam revealed normal vitals, pale conjunctiva but otherwise benign physical exam. Pertinent labs included WBC 3.9, hemoglobin 13.0, platelet 106, BUN 44, creatinine 1.4, AST 66, ALT 178, tacrolimus level 8, immuknow 134. Liver work-up revealed negative autoimmune antibodies, immunity to hepatitis A and B, and positive hepatitis E IgM. Quantitative HEV PCR was 757,000. Abdominal ultrasound with doppler revealed patent portal and hepatic vessels, and normal hepatic artery resistive indices. Diagnosis of acute hepatitis E infection in a hepatic allograft recipient was made. The source of the infection was traced back to an infected animal meat that patient had consumed 4 weeks prior to symptom onset. Patient was treated with ribavirin and his immunosuppression was adjusted. He recovered completely with normalization of liver enzymes and undetectable HEV PCR after 6 weeks. DISCUSSION: HEV infection is predominantly via fecal-oral transmission route and has been associated with animal meat consumption particularly deer, swine and chicken. The European Association for the Study of the Liver (EASL) guidelines suggest HEV testing in patients with unexplained flares of chronic liver disease and in all immunosuppressed patients with unexplained abnormal liver function tests. Solid organ transplant recipients who are viremic for more than 3 months after HEV infection are regarded as chronically infected and considered for treatment with ribavirin or peg-interferon alfa-2a. Our case illustrates the importance of testing for HEV infection in all patients with symptoms consistent with acute hepatitis infection, particularly in immunosuppressed individuals.

Anatomical variations of hepatic artery using the multidetector computed tomography angiography.

The frequency of normal and aberrant hepatic arteries differs among ethnicities. The aim of our work was to study the frequency of normal and aberrant hepatic arteries among Egyptians using multidetector computed tomography (MDCT) and to compare our prevalence with the prevalence of other nationalities. In addition, the gender differences of such variations were clarified. Moreover, the arterial feeding of hepatic segment IV was determined. The present study was carried out on 500 patients (409 males and 91 females). Abdominal CT was performed using two MDCT systems, a 64-row, and a 256-slice system. According to Michel's classification, the normal anatomy (type I) was observed in 369 (73.8%) cases, while anomalous hepatic arterial pattern was detected in 131 (26.2%) cases. These anomalies were distributed as follows: type II in 36 (7.2%) cases, type III in 60 (12%) cases, types IV and V in 5 cases for each (1% each), type VI in 14 (2.8%) and types VIII and IX in a single case for each (0.2% each). Neither type VII nor type X was detected. Nine (1.8%) unclassified cases were observed. According to Hiaat's classification, the anomalies were distributed as follows: type II in 41 (8.2%) cases, type III in 74 (14.8%) cases, type IV in 6 (1.2%) cases, type V in a single case (0.2%) and type VI in 2 (0.4%) cases. Finally, 7 (1.4%) unclassified cases were observed. Common hepatic artery (CHA) originated from coeliac trunk in 98% (79.8% males and 18.2% females). It originated from the abdominal aorta in 0.4% and from the superior mesenteric artery (SMA) in 0.4%. It was absent in 1.2%. Right hepatic artery (RHA) originated from the CHA in 86.6% (69.8% males and 16.8% females) and from the SMA in 13.2% (11.8% males and 1.4% females) and from the abdominal aorta in 0.2% (a single male case). Left hepatic artery (LHA) originated from the CHA in 91.2% and from the left gastric artery (LGA) in 8.8%. The most common origin of the segment IV blood supply was the LHA in 60.8%, followed by the RHA in 35%. Less commonly, blood supply derived from the hepatic artery proper (HAP) in 1%. Combined supply derived from RHA and LHA in 0.8%, from the LHA and HAP in 2% and the least encountered was from the RHA and HAP in 0.4%. Hepatic artery variations among Egyptians have a different distribution when compared to such variations among other species. The normal hepatic arterial pattern was observed in 73.8%, while the anomalous was detected in 26.2%. The CHA originated from the coeliac trunk in 98%, the RHA originated from the CHA in 86.6% and the LHA originated from the CHA in 91.2%. The most common arterial supply of the hepatic segment IV is derived from the LHA (60.2%).

A single-center clinical study of hepatic artery variations in laparoscopic pancreaticoduodenectomy: A retrospective analysis of data from 218 cases.

Hepatic artery variations increase the difficulty of laparoscopic pancreaticoduodenectomy (LPD). The safety and efficacy of LPD in the presence of aberrant hepatic arteries (AHA) must be further verified.Patients with normal and variant hepatic arteries who underwent LPD and preoperative arterial angiography were retrospectively analyzed. Variation type, intraoperative management, and clinical treatment outcomes were compared.There were 54 cases (24.8%) of AHA. The most common hepatic artery variation was accessory right hepatic artery (RHA) from the superior mesenteric artery (SMA, n = 12, 5.5%), followed by replaced RHA from the SMA (n = 10, 4.6%), accessory left hepatic artery from the SMA (n = 10, 4.6%), and replaced common hepatic artery from the SMA (n = 6, 2.8%). Each type of arterial variation was successfully preserved in all cases, and there were no significant effects on the evaluated surgical indices, conversion rate, incidence of postoperative complications, or follow-up results.Our findings indicated that preservation of AHAs during total LPD is feasible. There were no significant effects on surgical indices, incidence of postoperative complications, or follow-up outcomes.The influence of AHA on the safety and efficacy of LPD must be further verified. Patients with normal and variant hepatic arteries who underwent LPD and preoperative arterial angiography were retrospectively analyzed. There were 54 cases (24.8%) of AHA. There were no significant effects of AHAs on surgical indices, incidence of postoperative complications, or follow-up outcomes.

Replaced right hepatic artery and its segmental distribution

A case of replaced right hepatic artery arising from the superior mesenteric artery is presented with its segmental distribution and the morphometric features. The case was encountered in a 66-year-old formalin-fixed male cadaver during dissection for undergraduate lab education. Length and diameter of the replaced right hepatic artery were measured 63.10 mm and 3.6 mm, respectively. The replaced right hepatic artery coursed posterior to the portal vein initially, and then lateral to it. One of its branches entered into liver segments V and VIII, and the other entered into segments VI and VII. Left hepatic artery arose from the common hepatic artery and gave the middle hepatic artery 11.9 mm distal to its origin. Length and diameter of the middle hepatic artery were measured 30.2 mm and 1.2 mm, respectively. After giving a small branch to caudate lobe, the middle hepatic artery reached the quadrate lobe. The diameter and segmental distribution of replaced right hepatic artery was similar to the normal right hepatic artery described in earlier studies. The middle hepatic artery arose from the left hepatic artery at a substantial distance from the liver tissue in the presence of a replaced right hepatic artery. This is of clinical significance in liver transplantations as the arterial supply of segment IV is from the middle segmental artery. Keywords: liver; liver transplantation; replaced right hepatic artery; segmental distribution

Lymph node spread of gallbladder cancer from the perspective of embryologically-based anatomy and significance of the lymphatic basin along the embryonic right hepatic artery.

Lymph node metastasis from gallbladder cancer is often found in the pericholedochal area; however, these regional lymph nodes are not typically accompanied by arteries. We hypothesized that the artery accompanying pericholedochal lymph nodes was either the regressed embryonic right hepatic artery (eRHA) or an aberrant right hepatic artery (aRHA) remaining without regression. This study aimed to determine the artery supplying pericholedochal lymph nodes. We obtained serial tissue sections of resected specimens from 10 patients who underwent pancreaticoduodenectomy with combined resection of the superior mesenteric artery and vein and investigated the association between the distribution of enlarged lymph nodes and the course of blood vessels in each section. In 2 cases with aRHA, enlarged lymph nodes were distributed in the posterosuperior area, pancreaticoduodenal region and retroportal area along this artery. By contrast, no blood vessels accompanied enlarged lymph nodes in 8 patients exhibiting a normal hepatic artery branching pattern, although these nodes exhibited a distribution pattern similar to that of patients with the aRHA. Thus, the artery supplying pericholedochal lymph nodes appears to be either the regressed eRHA or an aRHA persisting without regression.

Pathology of the liver sinusoids

The hepatic sinusoids comprise a complex of vascular conduits to transport blood from the porta hepatis to the inferior vena cava through the liver. Under normal conditions, portal venous and hepatic artery pressures are equalized within the sinusoids, oxygen and nutrients from the systemic circulation are delivered to the parenchymal cells and differentially distributed throughout the liver acini, and proteins of liver derivation are carried into the cardiac/systemic circulation. Liver sinusoid structures are lined by endothelial cells unique to their location, and Kupffer cells. Multifunctional hepatic stellate cells and various immune active cells are localized within the space of Disse between the sinusoid and the adjacent hepatocytes. Flow within the sinusoids can be compromised by physical or pressure blockage in their lumina as well as obstructive processes within the space of Disse. The intimate relationship of the liver sinusoids to neighbouring hepatocytes is a significant factor affecting the health of hepatocytes, or transmission of the effects of injury within the sinusoidal space. Pathologists should recognize several patterns of injury involving the sinusoids and surrounding hepatocytes. In this review, injury, alterations and accumulations within the liver sinusoids are illustrated and discussed.

Hepatic artery pseudoaneurysm after surgical treatment for pancreatic cancer: minimally invasive angiographic techniques as the preferred treatment.

Background:Delayed intra-abdominal bleeding related to hepatic artery pseudoaneurysm is a potentially lethal complication after pancreaticoduodenectomy for pancreatic cancer. Locally advanced tumors, which result in vessel erosion or extensive operative skeletonization, may contribute to weakness of the arterial wall. Reoperation is often technically difficult with high rate of mortality; therefore, alternative less invasive options are ideal.Aims:The study was to present an alternative endovascular treatment of a large hepatic artery pseudoaneurysm after pancreatic resection for locally advanced multicystic adenocarcinoma.Materials and Methods:Transcatheteric mesenteric angiography with deployment of detachable coils in the pseudoaneurysm sac was utilized to manage the hepatic artery pseudoaneurysm.Results:Completion angiography confirmed cessation of contrast enhancement in the pseudoaneurysm sac with preservation of normal antegrade hepatic artery flow.Conclusion:Minimally invasive angiographic technique is the preferred treatment for hepatic artery pseudoaneurysm after pancreatic resections.

Abstract No. 303 - Quantitative analysis of tumor vasculature in hepatocellular carcinoma

Purpose To evaluate the complexity and irregularity of tumor vessels in hepatocellular carcinoma (HCC) patients using fractal analysis. Materials and Methods The institutional review board approved this study. Arteriograms of HCC patients were retrospectively studied using fractal anaylsis software (FracLar. jar) and compared with normal liver vessels. Sixteen patients with clinically confirmed HCC, 12 males 4 females, mean age 62.3± 4.3 year (ranged 50-70 years) old, were included in this study. Four normal hepatic arteriograms were obtained from trauma patients utilized as controls. The fractal dimension (a measure of irregularity) and lacunarity (a measure of texture) were recorded using a box counting technique. The data were analyzed using one-way ANOVA to compare different vessels fractal dimension and lacunarity, p≤0.05 was considered statistically significant. Results The fractal dimensions of the HCC tumor arteries and normal hepatic arteries were 1.8±0.05, and 1.8±0.06 (P≥0.05), respectively, and not statistically significant. The lacunarity of tumor arteries and the normal hepatic arteries were 0.48±0.17 and 0.52±0.12 (P≤0.05), respectively, and were significantly different. The fractal dimension and lacunarity of the large tumor mass were 1.84±0.04 and 0.34±0.09, and when compared to normal liver, both were statistically significant (P≤0.05). Conclusion The fractal dimensions of HCC tumor arteries are similar to normal hepatic arteries. However the lacunarities of the tumor vessel are smaller than of normal control’s and are statistically significant.

Hepatobiliary and Pancreatic: Extrahepatic biliary atresia in an adult

A teenager, aged 18, was referred for evaluation because of elevated serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) for 16 years. There were no significant abdominal or other symptoms. However, on physical examination, he had a large spleen, 8 cm below the left costal margin. Routine blood tests showed anemia, leucopenia and thrombocytopenia. Liver function tests revealed a normal serum bilirubin but elevated levels of ALT, AST, alkaline phosphatase (ALP) and gamma-glutamyl transpeptidase (GGT). Various investigations for viral hepatitis, autoimmune disease and Wilson's disease were unhelpful. An abdominal ultrasound study and computed tomography (CT) scan showed dilatation of intrahepatic ducts and splenomegaly. Magnetic resonance cholangiopancreatography (MRCP) showed cystic dilatation of the hilar bile duct and moderate dilatation of intrahepatic ducts. The gallbladder (GB) and common bile duct (BD) were clearly shown and the gallbladder appeared to be linked to intrahepatic ducts (Figure 1). Endoscopic retrograde cholangiopancreatography (ERCP) was also performed and showed contrast passing from the common bile duct into the cystic duct and gallbladder (Figure 2). The common hepatic duct was not outlined. Endoscopy revealed esophageal and gastric varices while CT angiography showed a normal hepatic artery, portal vein and inferior vena cava. Figure 1 Figure 2 At laparotomy, the patient had features of cirrhosis. An operative cholangiogram was performed by injection of contrast into the gallbladder and only showed contrast in the common bile duct, similar to findings at ERCP. In the process of mobilizing the gallbladder, bile ducts in the gallbladder bed were shown to communicate with the gallbladder. The common hepatic duct could not be identified but dissection revealed a hilar pouch containing bile. Two hepaticojejunostomies were performed to drain bile from the gallbladder bed and from the hilar pouch. Splenectomy was also performed. The anastomoses in the gallbladder bed were shown to be patent by passage of contrast through a stent. Liver function tests returned to normal after 8 months. This may be the first report of biliary atresia diagnosed in an adult. In this case, he had an unusual variant characterized by absence of the common hepatic duct (type II). The diagnosis was delayed because of the development of anastomoses between branches of the right hepatic duct and the gallbladder. Despite this, there was persistent cholestasis with the development of biliary cirrhosis and portal hypertension. The surgical procedure appears to have been helpful in the short-term but the longer-term outcome remains unclear. Contributed by

Clinical impact of right accessory hepatic artery injury in deceased donor livers

Right accessory hepatic artery (RAHA) injury at retrieval is a rare complication of deceased liver procurement. Arterial reconstruction is often required under these circumstances which could potentially increase the risk of hepatic artery thrombosis (HAT). The aim of this study is to investigate whether RAHA injury affects the incidence of HAT, early biliary complications, or 3-month graft and patient survival rates. All adult liver transplants performed between 1994 and February 2007 at Addenbrooke's Hospital, Cambridge, UK were considered for inclusion in the study. Grafts were divided into three groups depending on the presence of RAHA and injury (Group 1: normal anatomy and single hepatic artery anastomosis; Group 2: RAHA requiring reconstruction; Group 3: RAHA injury requiring reconstruction). Eight hundred and forty-four liver transplants were included in the study (Group 1: 654 grafts; Group 2: 63 grafts; Group 3: 14 grafts). The incidence of HAT (Group 1, 2.9%; Group 2, 6.4%; Group 3, 14.3%) was significantly different between the three groups (P=0.01); biliary complications at 3months (Group 1, 7.1%; Group 2, 11.1%; Group 3, 7.1%) were not significantly different. Graft and patient survival at 3months were significantly worse in Group 3 when compared with Group 2 (61.5 vs. 88.3%, P=0.01; 81.8 vs. 98.2%, P=0.02). This is the first study analysing the clinical impact of RAHA injury during liver procurement. We conclude that the use of liver grafts with RAHA injury does result in a higher HAT rate and is also associated with lower graft and patient survival rates at 3months.

Accessory hepatic artery: incidence and distribution

Background: Anatomic variations of the hepatic arteries are common. Preoperative identification of these variations is important to prevent inadvertent injury and potentially lethal complications during open and endovascular procedures. Objective: To evaluate the incidence, extra-hepatic course, and presence of side branches of accessory hepatic arteries, defined as an additional arterial supply to the liver in the presence of normal hepatic artery. Methods: Eighty-four human male cadavers were dissected using a transperitoneal midline laparotomy. The supra-celiac aorta, celiac axis, and hepatic arteries were dissected, and their trajectories were identified to describe arterial branching patterns. Results: Normal hepatic arterial anatomy was identified in 95% of the cadavers and six (5%) had accessory hepatic arteries. In five cadavers the accessory hepatic artery followed its course through the fissure for ligamentum venosum, and in one it coursed adjacent to the hepatic artery through the margin of the lesser omentum. One cadaver had a single side branch, which provided arterial blood supply to the left adrenal gland in the absence of any left inferior phrenic artery. Conclusion: Accessory hepatic artery most often follows the course of the hepatic fissure for ligamentum venosum. Albeit uncommonly found in 5% of cases, this finding should be identified during open and endovascular procedures to prevent inadvertent injury.