Anatomic variations in right liver living donors

Peculiarities of implantation of the right graft veins into the inferior vena cava during living donor liver transplantation

BACKGROUND

Living donor liver transplantation (LDLT) is a crucial alternative to deceased donor transplantation, especially in regions with limited access to cadaveric organs. Right lobe graft implantation into the inferior vena cava (IVC) requires advanced surgical techniques to optimize outcomes and reduce complications.

AIM

To compare two venous anastomosis techniques—direct polytetrafluoroethylene (PTFE) grafting of V5-V8 veins to the IVC vs triangulation to the right hepatic vein (RHV)—in terms of graft viability and postoperative outcomes.

METHODS

A retrospective analysis was conducted on 96 patients who underwent LDLT with right lobe grafts between 2014 and 2023. Patients were divided into three groups: (1) No venous outflow reconstruction; (2) PTFE graft direct anastomosis to the IVC; and (3) PTFE graft anastomosis using triangulation to the RHV. Perioperative and postoperative outcomes, including bile duct complications, alanine aminotransferase/aspartate aminotransferase levels, and graft perfusion, were compared across groups.

RESULTS

Group 3 (triangulation to RHV) showed significantly improved venous outflow, fewer complications, and faster normalization of liver function tests. Bile duct complications were highest in group 1 (12.8%) and lowest in group 3 (7%). Doppler ultrasonography revealed better graft perfusion in group 3 compared to groups 1 and 2.

CONCLUSION

Triangulation to the RHV improves graft viability, reduces biliary complications, and enhances early postoperative outcomes compared to direct PTFE grafting to the IVC.

Vascular liver segmentation: a narrative review on methods and new insights brought by artificial intelligence

Liver vessel segmentation from routinely performed medical imaging is a useful tool for diagnosis, treatment planning and delivery, and prognosis evaluation for many diseases, particularly liver cancer. A precise representation of liver anatomy is crucial to define the extent of the disease and, when suitable, the consequent resective or ablative procedure, in order to guarantee a radical treatment without sacrificing an excessive volume of healthy liver. Once mainly performed manually, with notable cost in terms of time and human energies, vessel segmentation is currently realized through the application of artificial intelligence (AI), which has gained increased interest and development of the field. Many different AI-driven models adopted for this aim have been described and can be grouped into different categories: thresholding methods, edge- and region-based methods, model-based methods, and machine learning models. The latter includes neural network and deep learning models that now represent the principal algorithms exploited for vessel segmentation. The present narrative review describes how liver vessel segmentation can be realized through AI models, with a summary of model results in terms of accuracy, and an overview on the future progress of this topic.

Laparoscopic left hepatectomy for a patient with an absence of portal bifurcation using real-time imaging: a case report

BACKGROUND

Absence of portal bifurcation is an extremely rare anomaly that should be recognized preoperatively, especially prior to a major hepatectomy.

CASE PRESENTATION

A 45-year-old woman presented with abdominal pain, and abdominal computed tomography (CT) revealed dilatation of both the common bile duct (CBD) and intrahepatic bile duct (IHBD). Endoscopic retrograde cholangiopancreatography (ERCP) showed CBD and IHBD stones (B2 and B4). The CBD stones were removed, but the IHBD stones could not be, yet there was no evidence of malignancy at the site of IHBD stenosis. Enhanced CT revealed a dilated IHBD, while three-dimensional CT images showed the left portal vein running through the ventral side of the middle hepatic vein, which was diagnosed as the absence of portal vein bifurcation (APB). Laparoscopic left hepatectomy was successfully performed using real-time indocyanine green (ICG) fluorescence imaging.

CONCLUSION

Surgeons should be aware of the possibility of APB, a rare portal vein anomaly, before performing major hepatectomy. Real-time ICG fluorescence imaging may be helpful to ensure the precise anatomy of the liver during laparoscopic surgery.

The Frequency of Anatomical Variants of the Bile Ducts: A Review Based on a Single Classification as Support for Cholangiographic Examinations

Complications arising from hepatobiliary surgery can have adverse effects on both the quality of life and the survival of patients. Magnetic resonance cholangiography (MRC) techniques are highly effective at revealing anatomical variants of the bile ducts and thus play a vital role in minimizing the occurrence of complications. The aims of this review are threefold: to ascertain the classifications utilized for categorizing anatomical variants of the bile ducts, to present the reported results on the prevalence of these anatomical variants, and to explore the diagnostic modalities employed to visualize these anatomical variants and associated complications during surgical procedures. A review of the literature was carried out using the Cochrane Library database and the PubMed, Medical Literature Analysis and Retrieval System Online (MEDLINE), and Google Scholar platforms. We conducted a comprehensive review of relevant studies to categorize the different anatomical variants according to the Huang classification. According to the Huang classification, our study showed type A1, 60.44%; type A2, 11.76%; type A3, 11.73%; type A4, 5.47%; type A5, 0.26%; and type B, which was identified in insignificant numbers (0.16%) or does not appear; additionally, variants that do not fit into the Huang classification have also been identified (10.18%). The Huang classification serves as an invaluable presurgical guide, aiding in the strategic planning of biliary interventions and effectively reducing the risk of iatrogenic complications, morbidity, mortality, and postoperative length of stay. MRC is still considered the noninvasive gold standard method for evaluating the bile ducts and their anatomical variations.

Effect of Donors' Biliary Variation on Postoperative Biliary Complications in Living Donor Liver Transplantation: A Single-Center Observational Study in Vietnam

BACKGROUND

Our study aims to evaluate the biliary anatomy variation according to the Varotti classification and its correlation with surgical outcomes for both donors and recipients undergoing living donor liver transplants (LDLTs).

METHODS

A retrospective analysis of 150 LDLT cases performed at a single center in Vietnam with preoperative radiologic evaluations and intraoperative surgical assessments to identify biliary variant anatomy. Postoperative biliary complications were documented and analyzed. Statistical analysis was performed to determine any significant associations between biliary variations and post-transplant outcomes.

RESULTS

One hundred fifty cases of LDLT at 108 Military Central Hospital from October 2017 to December 2022 were included in our study. Among the donors, the mean age was 30.89 ± 7.23, with male predominance (77.3%). The prevalence of type 1 biliary anatomy was 84.67%. Type 2, 3a, 3b, 4a, and 4b accounted for 5.33%, 2.67%, 5.33%, 0.67%, and 1.33% of cases, respectively. Donors' complications were witnessed in 7 cases (4.67%), and all needed intervention (Clavien-Dindo grade 3). Biliary complications were found in 36 (24.0%) recipients, with 22 (14.67%) cases of biliary stenosis and 16 (10.67%) cases of biliary leak, including 2 cases encountering both complications. Age, gender, graft type, preoperative liver function, biliary variant anatomy, number of graft orifices, Model for End-Stage Liver Disease score, and blood loss were not significant risk factors for recipients' biliary complications. Cold ischemia time significantly increased the biliary complication rate.

CONCLUSIONS

This study shows that biliary variant anatomy is common in living liver donors. Such variations should not be a contraindication to liver donation. However, accurate pre- and intraoperative radiologic and surgical evaluations are fundamental for a careful reconstruction plan.

Hilar Anatomy in 3035 Living Liver Donors: A Novel Classification for Donor Surgery and Suitability, Hepatic Surgeries, and Hepatobiliary Interventions

BACKGROUND

This study examines the vascular and biliary variations in 3035 liver donors. We propose a novel classification of hepatic arteries, portal veins, and bile ducts and clinically relevant donor classification.

METHODS

Preoperative imaging and operative details of 3035 donors from 2005 to 2020 were reviewed. Hilar anatomical variations were identified and grouped on the basis of incidence and clinical relevance.

RESULTS

Hilar structures are classified according to the numbers supplying or draining the graft: for the hepatic artery, right (R) and left (L), RA1/LA1 (1 artery), RA2/LA2 (2 arteries), and RA3/LA3 (3 arteries), respectively, further defined on the basis of the inflow trunk into C (for common hepatic artery), S (for superior mesenteric artery), and L (for left gastric artery); for the portal vein, RP1 (1 vein) and RP2 (2 veins) for the right lobe; and for the hepatic duct, RB1/LB1 (1 duct), RB2/LB2 (2 ducts), RB3 (3 right ducts), and RB4 (4 right ducts). Donors were classified on the basis of anatomical variations into 3 groups: class 1 and class 2 donors, who can donate liver with acceptable risks, and class 3 donors, who are high-risk donors because they are anatomically unacceptable ( Figures S1 to S4, SDC , http://links.lww.com/TP/C918 ).

CONCLUSIONS

Defining hilar anatomical variations and donor grouping into anatomy-based clinical classes helps in operative planning of donors, hepatobiliary surgeries, and interventional procedures.

Hepatic portal vein branching patterns according to different liver assessment methods and classifications of branching type

BACKGROUND

It is known that there are varying frequencies of hepatic portal vein branching patterns found in the literature. Studies use different methods and classifications to evaluate the anatomy of the portal vein, which limits accurate comparison between studies and the determination of true frequency of branching patterns in different populations. The aim of the present study was to investigate the intrahepatic branching of the portal vein in corrosive samples using different methods - somatoscopic and computed tomography (CT) and compare with similar studies as well as compare the reclassified data according to the most popular classifications used in the literature.

METHODS

A total of 105 liver corrosion specimens from the 1960-1980 period (51 male and 54 female individuals; min-max age variation - 21-90 y., M=59,46 y.) were investigated. The branching patterns of the hepatic portal vein (HPV), left (HPV-LB) and right branch of hepatic portal vein (HPV-RB), and their segmental branches were examined and scanned by CT. Standard HPV ramification was considered, when HPV divided into HPV-LB and HPV-RB, HPV-RB bifurcated to the anterior and posterior branches, and further segmental ramification into the superior and inferior branches was considered standard. We compared the HPV main branch length and diameter measurements between manual and CT method. A review of the literature was performed on portal vein branching variations.

RESULTS

The standard HPV ramification pattern was detected in 85.7% of the cases in both somatoscopic and CT evaluation. Variations related to the main branches were HPV trifurcation - 7.6%, posterior branch of right branch of hepatic portal vein from HPV - 4.8% and 5.7%, HPV quadrifurcation 1.9% and 1% respectively, in somatoscopic and CT evaluation. There was a significant difference between HPV-LB length and diameter in CT and manual measurements. According to the literature, more variations are seen using the CT method versus somatoscopic corrosion cast evaluation. The varying frequency in studies may be explained by a lack of one unanimous classification of branching patterns (some authors do not consider segmental variations as standard HPV ramification) and different evaluation methods.

CONCLUSION

Somatoscopic evaluation of the branching patterns of the hepatic portal vein in corroded specimens and their CT reconstructions did not differ significantly (which allows relatively accurate comparison of old specimens with newer data). However, the ability to evaluate the reconstructed 3D images of the specimens allowed a more accurate assessment of segmental branching and measurements of lengths and diameters. Standard HPV branching (according to a self-developed classification) in this study was 85.7%. Depending on the classification, the rate of standard branching in the same corrosive samples varied from 63.8% to 84.8% of all cases, indicating that the lack of a unified and stable classification makes it difficult to compare the results of different studies. Deviations from standard branching are very important in surgical procedures and liver transplantation.

Blood flow reconstruction in portal vein anatomical variations in right lobe living donor liver transplantation

Background. Adequate restoration of blood flow through the portal vein in the graft is only possible with a clear understanding of its anatomy in the donor.

The aim was to describe new and extend current data on the portal vein anatomy in a donor of the right liver lobe, to describe variants and formulate principles of portal reconstruction in right lobe living donor liver transplantation.

Material and methods. 306 living donor liver transplantations were performed from 2009 to 2021 in the State Research Center – Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency. The vascular anatomy of 518 potential donors was analyzed. Portal vein variants of the anatomy of right lobe graft were assessed.

Results. Nine types and 3 subtypes of portal vein branching were evaluated. A, B, C, D, E types match the types described earlier in Nakamura classification. Subtypes B1, B2 и D1 are specifications of types B and D. Types F, G, H, I have been described additionally. The incidence of types and subtypes where reconstruction was made: type A (82%), B (4.6%), B1 (3.9%), B2 (1.3%), C (3.9%), D (3.9%). The incidence of E, G, H, I types among 518 potential donors was 0.4%, 0.6%, 0.2%, 0.4%, respectively. The recipient portal vein complications were detected in 12 cases (3.9%), where 3(25%) were Class 3b according to Clavien-Dindo and 9(75%) of Clavien-Dindo Class 2. There were no correlations between portal vein complications and the method of portal vein reconstruction. (p<0.05). No complications occurred with portal vein in donors.

Conclusion. The existing classification of right liver graft portal vein has been updated and detailed. A certain way of reconstruction has been proposed for each portal vein type. Anatomical types in which donation and transplantation are contraindicated have been specified.

Endoscopic Treatment of Malignant Hilar Biliary Obstruction

Stent implantation is an effective approach for palliative treatment of Bismuth-Corlette type III-IV malignant hilar biliary obstructions (MHBOs). In this article, we reviewed the currently used access methods for biliary stent placement (percutaneous transhepatic biliary drainage, endoscopic biliary drainage, endosonography guided biliary drainage), the available stent types (plastic stent, self-expanding metallic stent, full cover self-expanding metallic stent, radioactive self-expanding metallic stent), major approaches (unilateral, bilateral) and deployment methods (stent-in-stent, stent-by-stent). Finally, this review gives an outlook on perspectives of development in stenting and other palliative methods in MHBO.

Comparison of pure laparoscopic donor right posterior sectionectomy versus right hemihepatectomy for living donor liver transplantation

The right posterior section (RPS) graft for living donor liver transplantation is an alternative graft in a live liver donor with insufficient remnant left lobe volume and portal vein anomaly. Although there have been some reports regarding pure laparoscopic donor right posterior sectionectomy (PLDRPS), no study has compared PLDRPS versus pure laparoscopic donor right hemihepatectomy (PLDRH). The aim of our study was to compare the surgical outcomes of PLDRPS versus PLDRH at centers achieving a complete transition from open to laparoscopic approach in liver donor surgery. From March 2019 to March 2022, a total of 351 living donor liver transplantations, including 16 and 335 donors who underwent PLDRPS and PLDRH, respectively, were included in the study. In the donor cohort, there were no significant differences in major complication (≥grade III) rate and comprehensive complication index between the PLDRPS versus PLDRH group (6.3% vs. 4.8%; p = 0.556 and 2.7 ± 8.6 vs.1.7 ± 6.4; p = 0.553). In the recipient cohort, there was a significant difference in major complication (≥grade III) rate (62.5% vs. 35.2%; p = 0.034) but no significant difference in comprehensive complication index (18.3 ± 14.9 vs. 15.2 ± 24.9; p = 0.623) between the PLDRPS and PLDRH groups. PLDRPS in live liver donors with portal vein anomaly and insufficient left lobe was technically feasible and safe with experienced surgeons. The PLDRPS group might be comparable with the PLDRH group based on the surgical outcomes of donors and recipients. However, in terms of recipient outcomes, more careful selection of donors of the RPS graft and further research in a large number of cases are necessary to evaluate the usefulness of PLDRPS.

Anatomical variations in living donors for liver transplantation-prevalence and relationship

PURPOSE

Living donor liver transplantation (LDLT) is a widely accepted option to address the lack of a deceased liver program for transplantation. Understanding vascular and biliary anatomy and their variants is crucial for successful and safe graft harvesting. Anatomic variations are common, particularly in the right hepatic lobe. To provide evidence for screening potential liver transplant donors, the presence of vascular and biliary anatomic variations in Pakistan's preoperative assessment of transplantation donor candidates was explored.

METHODS

This retrospective cross-sectional study evaluated the hepatic artery, portal vein, hepatic vein, and biliary variations in living liver donors. The study included 400 living liver donors; data were collected from March 2019 to March 2023. We used a CT scan and MRCP to assess the anatomical variations.

RESULTS

The study examined 400 liver donors aged 18 to 53 years. Conventional arterial anatomy was the most common (65.8%), followed by replaced right hepatic artery (16%) and replaced left hepatic artery (10.8%). Conventional type 1 biliary anatomy was seen in 65.8% of cases. The dominant right hepatic vein was found in 13.3% of donors. There was a significant association between the prevalence of variant portal venous anatomy with variant biliary anatomy.

CONCLUSION

Variations of the hepatic arterial, portal venous, and biliary systems are frequent and should be carefully evaluated while selecting a suitable living donor. A strong relationship between variant portal venous and biliary anatomy was found. These findings can aid in selecting suitable candidates and improving surgical planning for liver transplantation.

Single-Center Experience in Managing Right Liver Grafts From Trifurcation or Independent Right Posterior Portal Vein in Adult Living Donor Liver Transplantation

BACKGROUND

The right liver graft has sometimes been from the trifurcation portal vein (TPV) or independent right posterior portal vein (IRPPV). Managing these PV anatomies to increase the recipient's survival rate remains challenging. Many published techniques could overcome this problem, such as simple unification venoplasty (SUV), autologous portal Y-graft interposition, conjoined unification venoplasty (CUV) with a baseball-like conduit, and SUV plus circumferential fence-like vein extension. This study reviewed our strategy for managing the right liver grafts from TPV or IRPPV in adult living donor liver transplantation (aLDLT).

METHODS

We enrolled the study population who underwent aLDLT using the grafts with TPV or IRPPV at our institute from October 2004 to October 2022. We analyzed the reconstruction methods for these grafts and postoperative PV complications in donors and recipients.

RESULTS

During the study period, of 528 aLDLT recipients, we identified 26 donors with TPV (n = 10) or IRPPV (n = 16). Eight grafts from TPV had a single PV orifice. The other 18 grafts had dual right PVs that underwent initial PV management, including SUV (n = 13), recipient's right and left portal veins to graft's dual PVs (n = 2), Y-graft interposition (n = 1), CUV (n = 1) and SUV with fence-like vein extension (n = 1). One SUV graft changed to fence venoplasty due to significant tension for PV anastomosis. The acute right posterior PV thrombus and anterior PV stenosis happened in 2 cases with Y-graft interposition and native PVs direct anastomosis. One donor with TPV had portal vein thrombosis and needed thrombectomy with vein patch repair.

CONCLUSIONS

The graft from TPV should be carefully planned. A single PV orifice may be feasible but not always possible. An SUV could cover most IRPPVs, but if the distance between the right anterior and posterior PVs is a problem, CUV would be an alternative method. In addition, SUVs with fence venoplasty could relieve PV anastomosis tension.

How to deal with right hepatic artery coming from the superior mesenteric artery during minimally invasive pancreaticoduodenectomy: A systematic review

BACKGROUND

Anatomical variations in the liver arterial supply are quite common and can affect the surgical strategy when performing a minimally invasive pancreaticoduodenectomy (MIPD). Their presence must be preemptively detected to avoid postoperative liver and biliary complications.

DATA SOURCES

Following the PRISMA guidelines and the Cochrane protocol we conducted a systematic review on the management of an accessory or replaced right hepatic artery (RHA) arising from the superior mesenteric artery when performing an MIPD.

RESULTS

Five studies involving 118 patients were included. The most common reported management of the aberrant RHA was conservative (97.0%); however, patients undergoing aberrant RHA division without reconstruction did not develop liver or biliary complications. No differences in postoperative morbidity or long-term oncological related overall survival were reported in all the included studies when comparing MIPD in patients with standard anatomy to those with aberrant RHA.

CONCLUSIONS

MIPD in patients with aberrant RHA is feasible without increase in morbidity and mortality. As preoperative strategy is crucial, we suggested planning an MIPD with an anomalous RHA focusing on preoperative vascular aberrancy assessment and different strategies to reduce the risk of liver ischemia.

Optimal Intervention for Initial Treatment of Anastomotic Biliary Complications After Right Lobe Living Donor Liver Transplantation

Background: This study evaluated endoscopic retrograde cholangiopancreatography (ERCP) and percutaneous transhepatic biliary drainage (PTBD) as interventions for patients with anastomotic biliary complications (ABC) after living donor liver transplantation (LDLT).

Methods: Prospectively collected data of patients who were diagnosed with ABC after LDLT between January 2013 and June 2017 were retrospectively reviewed.

Results: There were 57 patients who underwent LDLT with a right liver graft using duct-to-duct biliary reconstruction and experienced ABC. Among the patients with RAD involvement, there were no significant differences in the intervention success (p = 0.271) and patency rates (p = 0.267) between ERCP and PTBD. Similarly, among the patients with RPD involvement, there were no significant differences in the intervention success (p = 0.148) and patency rates (p = 0.754) between the two procedures. Graft bile duct variation (p = 0.013) and a large angle between the recipient and graft bile duct (R-G angle) (p = 0.012) significantly increased the likelihood of failure of ERCP in the RAD. When the R-G angle was greater than 47.5°, the likelihood of ERCP failure increased.

Conclusion: We recommend PTBD when graft bile duct variation is presented in patients with RAD involvement and/or when the R-G angle is greater than 47.5°.

Precision anatomy for safe approach to pancreatoduodenectomy for both open and minimally invasive procedure: A systematic review

BACKGROUND

Minimally invasive pancreatoduodenectomy (MIPD) has recently gained popularity. Several international meetings focusing on the existing literature on MIPD were held; however, the precise surgical anatomy of the pancreas for the safe use of MIPD has not yet been fully discussed. The aim of this study was to carry out a systematic review of available articles and to show the importance of identifying the anatomical variation in pancreatoduodenectomy.

METHODS

In this review, we described variations in surgical anatomy related to MIPD. A systematic search of PubMed (MEDLINE) was conducted, and the references were identified manually.

RESULTS

The search strategy yielded 272 articles, with 77 retained for analysis. The important anatomy to be considered during MIPD includes the aberrant right hepatic artery, first jejunal vein, first jejunal artery, and dorsal pancreatic artery. Celiac artery stenosis and a circumportal pancreas are also important to recognize.

CONCLUSIONS

We conclude that only certain anatomical variations are associated directly with perioperative outcomes and that identification of these particular variations is important for safe performance of MIPD.

Unraveling Variations in Celiac Trunk and Hepatic Artery by CT Angiography to Aid in Surgeries of Upper Abdominal Region

Understanding of variations in the course and source of abdominal arteries is crucial for any surgical intervention in the peritoneal space. Intricate surgeries of the upper abdominal region, such as hepato-biliary, pancreatic, gastric and splenic surgeries, require precise knowledge of regular anatomy and different variations related to celiac trunk and hepatic artery. In addition, information about the origin of inferior phrenic artery is important in conditions such as hepatocellular carcinoma and gastroesophageal bleeding management. The present study gives an account of anatomical variations in origin and branching pattern of celiac trunk and hepatic artery by the use of CT (computed tomographic) angiography. The study was performed on 110 (66 females and 44 males) patients in a north Indian population. Results unraveled the most common celiac trunk variation as hepatosplenic trunk with left gastric artery, which was observed in 60% of cases, more common in females than in males. Gastrosplenic and hepato-gastric trunk could be seen in 4.55% and 1.82% cases respectively. Gastrosplenic trunk was more commonly found in females, whereas hepato-gastric trunk was more common in males. A gastrosplenic trunk, along with the hepato-mesenteric trunk, was observed in 1.82% cases and was more common in males. A celiacomesenteric trunk, in which the celiac trunk and superior mesenteric artery originated as a common trunk from the aorta, was seen only in 0.91% of cases, and exhibited an origin of right and left inferior phrenic artery from the left gastric artery. The most common variation of hepatic artery, in which the right hepatic artery was replaced and originated from the superior mesenteric artery, was observed in 3.64%, cases with a more common occurrence in males. In 1.82% cases, the left hepatic artery was replaced and originated from the left gastric artery, which was observed only in females. Common hepatic artery originated from the superior mesenteric artery, as observed in 1.82% cases, with slightly higher occurrence in males. These findings not only add to the existing knowledge apart from giving an overview of variations in north Indian population, but also give an account of their correlation with gender. The present study will prove to be important for various surgeries of the upper abdominal region.

Incidence of Extrahepatic Portal Vein Anatomic Variations and Their Clinical Implications in Daily Practice

Anatomical variations of the portal vein are relatively common and can affect the outcomes of hepatic resections, transplantations and interventional radiological procedures. The aim of this study was to review the literature regarding extrahepatic portal vein anomalies. Two main databases were searched for suitable articles, and results concerning more than 3,700 patients were included in the analysis. The most common anatomical variations of the portal vein were trifurcation and having a right posterior portal vein as the first branch of the main portal vein; these anomalies were found in 11.7% and 10.8% of cases, respectively.

Imaging Evaluation of Living Liver Donor Candidates: Techniques, Protocols, and Anatomy

The need for liver transplants is increasing because the prevalence of liver diseases and the indications for transplants are growing. In response to the shortage of grafts from deceased donors, more transplants are being performed worldwide with grafts from living donors. Radiologic evaluation is an integral component in the assessment of donor candidates to ensure their eligibility and to choose the most appropriate surgical approach. MRI is the preferred modality for evaluation of the liver parenchyma and biliary tree. In most centers, a combination of MRI and CT is used to take advantage of the higher spatial resolution of CT for evaluation of arteries. However, MRI-only assessment is feasible. In addition to assessment of the liver parenchyma for abnormalities such as steatosis, a detailed evaluation of the hepatic vascular and biliary system for pertinent anatomic variants is crucial, because these variants can affect surgical techniques and outcomes in both recipients and donors. In this pictorial article, after a brief review of the most common surgical techniques and postsurgical liver anatomy, the biliary and vascular anatomy are discussed, with specific attention paid to the variants that are pertinent to this surgical procedure. The roles of liver segmentation and volumetric assessment and current imaging techniques and protocols are also discussed. Online supplemental material is available for this article. ©RSNA, 2021.

Surgical relevance of anatomic variations of the right hepatic vein

BACKGROUND

Variations in the anatomy of hepatic veins are of interest to transplant surgeons, interventional radiologists, and other medical practitioners who treat liver diseases. The drainage patterns of the right hepatic veins (RHVs) are particularly relevant to transplantation services.

AIM

The aim was to identify variations of the patterns of venous drainage from the right side of the liver. To the best of our knowledge, there have been no reports on RHV variations in in a Caribbean population.

METHODS

Two radiologists independently reviewed 230 contrast-enhanced computed tomography scans performed in 1 year at a hepatobiliary referral center. Venous outflow patterns were observed and RHV variants were described as: (1) Tributaries of the RHV; (2) Variations at the hepatocaval junction (HCJ); and (3) Accessory RHVs.

RESULTS

A total of 118 scans met the inclusion criteria. Only 39% of the scans found conventional anatomy of the main hepatic veins. Accessory RHVs were present 49.2% and included a well-defined inferior RHV draining segment VI (45%) and a middle RHV (4%). At the HCJ, 83 of the 118 (70.3%) had a superior RHV that received no tributaries within 1 cm of the junction (Nakamura and Tsuzuki type I). In 35 individuals (29.7%) there was a short superior RHV with at least one variant tributary. According to the Nakamura and Tsuzuki classification, there were 24 type II variants (20.3%), six type III variants (5.1%) and, five type IV variants (4.2%).

CONCLUSION

There was significant variation in RHV patterns in this population, each with important relevance to liver surgery. Interventional radiologists and hepatobiliary surgeons practicing in the Caribbean must be cognizant of these differences in order to minimize morbidity during invasive procedures.

Long-Term Safety and Efficacy of Pure Laparoscopic Donor Hepatectomy in Pediatric Living Donor Liver Transplantation

Laparoscopic living donor hepatectomy for transplantation has been well established over the past decade. This study aimed to assess its safety and feasibility in pediatric living donor liver transplantation (LDLT) by comparing the surgical and long-term survival outcomes on both the donor and recipient sides between open and laparoscopic groups. The medical records of 100 patients (≤17 years old) who underwent ABO-compatible LDLT using a left lateral liver graft between May 2008 and June 2016 were analyzed. A total of 31 donors who underwent pure laparoscopic hepatectomy and their corresponding recipients were included in the study; 69 patients who underwent open living donor hepatectomy during the same period were included as a comparison group. To overcome bias from the different distributions of covariables among the patients in the 2 study groups, a 1:1 propensity score matching analysis was performed. The mean follow-up periods were 92.9 and 92.7 months in the open and laparoscopic groups, respectively. The mean postoperative hospital stay of the donors was significantly shorter in the laparoscopic group (8.1 days) than in the open group (10.6 days; P < 0.001). Overall, the surgical complications in the donors and overall survival rate of recipients did not differ between the groups. Our data suggest that the laparoscopic environment was not associated with long-term graft survival during pediatric LDLT. In addition, the laparoscopic approach for the donors did not adversely affect the corresponding recipient's outcome. Laparoscopic left lateral sectionectomy for living donors is a safe, feasible, and reproducible procedure for pediatric liver transplantation.

Clinical Importance of Main Portal Vein and Right Portal Vein Variations: A Prevalence Study With 128-Slice Multidetector Computed Tomography

OBJECTIVES

The portal vein variation type significantly affects the outcome of transplant surgery, hepatectomies, and interventional radiological procedures. To reveal variation types, especially rare types, we used high-technology multidetector computed tomography.

MATERIALS AND METHODS

We evaluated multiphase abdominal multidetector computed tomography scans of 278 consecutive patients. Multidetector computed tomography scans were processed for axial, coronal, and axial-oblique multiplane reformation and for maximum intensity projection. Variations of the main portal vein and right portal vein were simulta-neously analyzed by 2 radiologists. Prevalence of each variation and differences in sexes were investigated.

RESULTS

Variant anatomy was detected in 29.5% of main portal veins and 20.9% of right portal veins. There was no statistical difference between sexes. Type 3 was reported as the most frequent variant of main portal vein, whereas type 4 was the most frequent variant of right portal vein. Some miscellaneous types were also ascertained.

CONCLUSIONS

Different types of anatomic variations may adversely affect the course of surgery and interventional radiological procedures. Fortunately, radiologists can now discover the critical types by using the new generation multidetector computed tomography with 3-dimensional reconstruction techniques. This information should be included in the radiology reports of patients who are scheduled for major surgery.

Comprehensive classification of anatomical variants of the main biliary ducts

This systematic review provides the most comprehensive overview of intrahepatic biliary anatomical variants to date. Additionally, it proposes a clinically focused, prevalence-based classification system based on meta-analysis of a large pooled dataset whilst incorporating the merits of previous classification systems.

Hepatic artery classification based on three-dimensional CT

BACKGROUND

Precise classification of the hepatic artery is helpful for preoperative surgical planning in hepatobiliary-pancreatic surgery. However, the anatomy of hepatic arteries is variable. This study investigated anatomical variation using three-dimensional visualization and evaluation (3DVE) to develop a nomenclature system.

METHODS

The origin and course of the hepatic artery were tracked and analysed by using three-dimensional visualization of CT images acquired between 2013 and 2017. The new classification and nomenclature system, named CRL, was developed based on the origins of the common, right and left hepatic arteries.

RESULTS

Scans from 770 adults were evaluated. Preoperative 3DVE correlated better with surgical findings than the original CT images alone. Using the CRL classification system, hepatic arteries were divided into nine subtypes. Only 87·4-89·2 per cent of the hepatic arteries of 610 living-donor liver transplant donors were depicted in Michels', Hiatt's or Varotti's classification, compared with 100 per cent identified by the CRL classification. The CRL classification was validated against external data sets from previous studies, with 99·6-100·0 per cent of patients classified by the CRL system.

CONCLUSION

The CRL classification covers hepatic artery variants and may be used for planning liver surgery.

Rare combined variations of accessory left hepatic artery and accessory right hepatic artery: a case report and literature review

Variations in the hepatic artery are commonly described in the literature, which is vital for the success procedure of all hepatobiliary surgery. Usually a variation occurs in either the accessory right hepatic artery (aRHA) or the accessory left hepatic artery (aLHA). However, we report an extremely rare case where the variation occurs in both simultaneously. We over served the aRHA arising from the gastroduodenal artery and branching into the superior pancreatic duodenum artery, while the aLHA arose from the common hepatic artery and branched into right gastric artery. This situation has never been reported in literature. We will discuss the meaning of this hepatic artery variation in a clinical setting.

Clinical investigation of the cystic duct variation based on the anatomy of the hepatic vasculature

PURPOSE

Anatomical variation of the cystic duct (CD) is rare but can result in misunderstanding of the CD anatomy during laparoscopic cholecystectomy, potentially leading to bile duct injury. Therefore, the precise preoperative identification of CD variation is important. However, preoperative imaging analyses of the biliary system are not always possible or sufficient. We therefore investigated CD variations based on the anatomy of the hepatic vasculature.

METHODS

This study enrolled 480 patients who underwent imaging before hepatobiliary pancreatic surgery. We assessed the variation of the CD and hepatic vasculature and evaluated the correlations among these variations.

RESULTS

A variant CD anatomy was identified in 12 cases (2.5%) as CD draining into the right hepatic bile duct (BD) in 4 cases and into the right posterior BD in 8 cases. CD variation was significantly more common in cases with portal vein (PV) and BD variation than in those without the variation. We developed a scoring system based on the presence of PV and BD variations that showed good discriminatory power for identification of CD variants.

CONCLUSION

Cases with a variant CD anatomy were more likely to exhibit variant PV and BD anatomies than cases with a normal CD anatomy. These findings will be useful for the preoperative identification of CD variants.

Pre-hepatic and pre-pancreatic transplant donor evaluation

Innovations in surgical techniques coupled with advances in medical and pharmacological management in the past few decades have enabled organ transplantation to become integral to the management of end stage organ failure. In this review article, we will review the role of the radiologist in the work up of liver and pancreas donors during evaluation of their donor candidacy. The critical role of imaging in assessing the parenchymal, biliary and vascular anatomy in liver donor candidates will be reviewed, as well as highlighting the anatomical findings that may pose a contraindication to transplantation. The limited role of imaging in pancreas donor evaluation is also covered, as well as a brief overview of the surgical techniques available and how the radiologist's findings influence operative technique selection.

Aberrant left hepatic arteries arising from left gastric arteries and their clinical importance

BACKGROUND

The Aberrant Left Hepatic Artery (ALHA) is replaced when it does not originate from the hepatic artery proper and it is the only supply to that part of the liver, while an accessory artery coexists with a normal artery. The aim of this systematic review is to evaluate the incidence of ALHAs including the one arising from the Left Gastric Artery, also named Hyrtl's artery.

METHODS

A literature search in PubMed, SCOPUS, WOS and Google Scholar was performed. The risk of bias was assessed by means of the AQUA tool. The main outcome was the prevalence of ALHA. Secondary outcomes were the prevalence of the accessory and replaced left hepatic arteries. A subgroup analysis was conducted by geographic region and type of evaluation.

RESULTS

This review included 57 studies, with a total of 19,284 patients. The majority of the studies involved the use of radiological techniques -especially Angio-CT-and were performed in Asia. The overall risk of bias was moderate. The overall prevalence of the ALHA was 13.52%; the overall prevalence was 8.26% for the Replaced ALHA and 5.55% for the Accessory ALHA. In the 18 studies that employed Michels' classification, Type II had the lowest prevalence (0.36%) and Type VII the highest prevalence (6.62%).

DISCUSSION

Some of the studies included did not distinguish between the ''replaced'' and ''accessory'' ALHA (34.25%). Some surgical dissection techniques proved insufficient for the localization of other hepatic arteries. These results suggest that an accurate preoperative radiological evaluation is needed to localize replaced arteries.

[Biliary system : What does the surgeon want to know from the radiologist?]

CLINICAL/METHODICAL ISSUE

Exact diagnostic procedures are prerequisite for surgical treatment of bile duct diseases.

STANDARD RADIOLOGICAL METHODS

Magnetic resonance cholangiopancreatography may be supplemented by computed tomography (CT) for planning surgical interventions, for staging diagnostics in malignancies and for imaging the vascular anatomy in the upper abdomen.

METHODICAL INNOVATIONS

Statements from magnetic resonance cholangiopancreatography (MRCP) and CT may be supplemented via digital workup in selected cases of transplantation medicine and in liver surgery. Thus, a virtual resection planning including volumetry of the individual liver segments can be realized.

PERFORMANCE

Magnetic resonance cholangiopancreatography provides for exact imaging of intrahepatic and extrahepatic bile ducts as well as those situated within the head of the pancreas and their pathologies.

PRACTICAL RECOMMENDATIONS

Radiological diagnostics of bile duct malignancies, benign outflow obstructions, in transplantation medicine and in postoperative complication management are an indispensable prerequisite in surgical treatment.

[Influence of bile duct anatomy on biliary complications in hepatic right lobe living donors]

Perioperative morbidity in the living donation of partial livers is mainly due to infections and biliary complications. Bile duct anatomy variants, in particular of the right system, are suspected to be causative. We investigated the influence of bile duct variants on the incidence of biliary donor complications in donations of the right liver lobe. We analyzed 103 donors. Twelve patients had a bile leak that required treatment. All of these were treated endoscopically without any residual defect. We did not see a central extrahepatic bile duct lesion Nagano type C. The anatomic variant Huang A3 is a challenge with respect to the surgical technique. Three of 17 patients with biliary anatomy Huang A3 developed leaks. The bile duct anatomy can be carefully evaluated by magnetic resonance cholangiopancreatography (MRCP) and intraoperative cholangiography. The anatomic variant Huang A3 warrants particular attention for the closure of the bile duct orifice.

Vascular Anomalies of the Extrahepatic Artery as a Predictable Risk Factor for Complications After Liver Transplant

OBJECTIVES

Vascular variations of the extrahepatic artery occur in up to 50% of the population. Exact knowledge of any anomalies is of great significance in hepatobiliary surgery to avoid perioperative complications. In fact, in liver transplant, vascular complications are rare but have a major impact on graft function and survival. This study evaluated variations of the extrahepatic artery in donors and recipients as risk factors for vascular complications after liver transplant.

MATERIALS AND METHODS

From January 2010 until June 2015, 469 liver transplant procedures were performed at our institution. We included 323 patients in our retrospective analysis after exclusion of retransplants, split-livertransplants, and pediatric patients. We analyzed the impact of anatomic variations of recipients and donors on postoperative vascular complications and organ and patient survival.

RESULTS

Of total study recipients, 71.2% had a normal vascular supply according to Michel classification I. However, these patients developed significantly more vascular complications (25.65%) than those with vascular anomalies (15.05%), especially showing higher incidence of arterial stenosis (8.26% vs 2.15%). In contrast, vascular variations in donors and the need for a vascular reconstruction of the graft led to significantly higher mortality (26.76% vs 15.48%). An abnormality of the graft did not influence incidence of postoperative complications or graft survival.

CONCLUSIONS

Unexpectedly, recipients with variations of the hepatic artery and grafts with an abnormal arterial supply did not show higher rates of com-plications or mortality. Only vascular reconstruction of the graft before transplant raised the mortality of recipients.

Embryology, Anatomy, and Imaging of the Biliary Tree

"The anatomy of the biliary tree is notoriously variable. This variation is the bane of the hepatobiliary surgeon, to whom an understanding of biliary anatomic variation is key to the planning and safe conduct of liver surgery, from oncological resections to split-liver transplantation. The hepatic diverticulum, also termed "the liver bud," is the first semblance of the biliary system in the human embryo. A variety of techniques used in the mid twentieth century for imaging the biliary tree have since been abandoned in favor of more practical, safer, less invasive, and more sensitive and specific contemporary methods."

Rare anatomic variation of the hepatic arterial blood supply: case report and literature review

PURPOSE

Our aim is to present a rare case of anatomic variation of the arterial blood supply to the liver because preoperative knowledge of hepatic vascular variations is mandatory in hepatic surgery and liver transplantation.

METHODS

We present a case of unusual arterial blood supply to the liver, a right hepatic artery coming from the splenic artery, associated to a classical common hepatic artery and a left hepatic artery from the left gastric artery. Preoperative diagnosis was made using CT-scan and 3D reconstruction.

RESULTS

The right hepatic artery was found behind the portal vein and its diameter showed its importance in the vascularisation of the liver. To our knowledge this type of variation has only twice been described before. The accuracy of the 3D reconstruction allowed us to adopt the best surgical strategy to avoid lesions of the two accessory arteries which proved important sources of blood supply.

CONCLUSIONS

Precise preoperative evaluation of liver blood supply has great importance on surgical, transplantation strategy and outcome and rare anatomic variations have to be known to avoid lesions of potentially important arteries. New techniques of 3D reconstruction can ease the preoperative recognition of such difficult anatomic variations.

Feasibility and Outcomes of Direct Dual Portal Vein Anastomosis in Living Donor Liver Transplantation Using the Right Liver Graft With Anatomic Portal Vein Variations

BACKGROUND

Portal vein (PV) reconstruction is a crucial factor in successful living donor liver transplantation (LDLT). In LDLT using the right liver grafts with anatomic PV variations, we sometimes encounter dual PV anastomosis. In this study we describe PV variations of donor liver in detail as well as our experiences with PV reconstruction in right liver grafts with PV variations.

METHODS

We performed LDLT in 149 recipients between 2002 and 2016. PV variations of donor liver were classified into 3 major anatomic patterns, and we retrospectively analyzed the procedure and postoperative complications of PV anastomosis.

RESULTS

PV variations in donor livers were classified as type A (normal type) in 125 patients, type B (trifurcation type) in 7 (4.7%), and type C (caudal origin of the right posterior branch) in 17 (11.4%). Among 75 right liver grafts, 10 (13.3%) had anatomic PV variations. In 9 of 10 recipients, dual PV of the graft were anastomosed to dual PV branches of the recipient in direct end-to-end fashion. In the remaining recipient, the posterior portal branch of the graft was anastomosed to the recipient portal trunk through the interposed venous graft in end-to-end fashion and the anterior portal branch of the graft was anastomosed to the side wall of the interposed venous graft. These 10 recipients did not develop any postoperative complications associated with PV anastomosis, although 3 of the 149 recipients (2.0%) developed complications associated with PV anastomosis, such as thrombosis and necrosis.

CONCLUSION

Dual PV anastomosis of the right liver graft is safe and feasible in LDLT, even in anatomic PV variations.

Anatomy of the Right Anterior Sector of the Liver and Its Clinical Implications in Surgery

BACKGROUND

Surgery remains the gold standard both for delimited hepatocellular carcinoma by selective anatomic liver segentectomy and for colorectal liver metastases by parenchymal sparing liver resection. Right anterior sector (RAS) (segments V-VIII; Couinaud) is the largest and most difficult sector to operate on. A better knowledge of its segmentation could prevent postoperative remnant liver ischemia and its impacts on patient's survival.

METHODS

A literature search was conducted in PubMed for papers on anatomy and surgery of the right anterior sector.

RESULTS

Segmentation of the RAS depended of the anatomic variations of the third-order portal branches. Cranio-caudal segmentation was the most commonly found (50-53%), followed by ventro-dorsal (23-26%), trifurcation (13-20%), and quadrifurcation types (5-11%). Ventral and dorsal partial or total subsegmentectomy seemed accessible in 47 to 50% of patients, including bifurcation, trifurcation, and quadrifurcation types, and could spare up to 22% of the total liver volume. The RAS hepatic vein was present in 85-100% of the patients and could be used as a landmark between RAS dorsal and ventral part in 63% of patients. Reported overall morbidity rate of RAS subsegmentectomy ranged from 33 to 59% among studies with a postoperative major complication rate (Clavien-Dindo ≥ III) ranging around 18% and a biliary leakage rate from 16 to 21%. In-hospital reported mortality rate was low (0-3%), and results were comparable to "classic" liver resections. RAS subsegmentectomy remains a complex procedure; median operating time ranged from 253 to 520 min and median intraoperative blood loss reached 1255 ml.

CONCLUSION

Better knowledge of RAS anatomy could allow for parenchymal preservation by using subsegmentectomy of the RAS, selective or as a part of a major hepatectomy.

A case of a right accessory hepatic duct diagnosed during a Whipple procedure

INTRODUCTION

Although anatomic variations of the bile tract are relatively common and can be present in about 28% of patients, existence of an accessory right hepatic duct that confluence on the common bile duct is quite rare.

PRESENTATION OF CASE

We present a rare case of a caucasian 78-years-old patient, with accessory right hepatic duct which was diagnosed intraoperatively. The patient was submitted to Whipple procedure due to a mass in the head of pancreas. Intraoperatively, an accessory right hepatic duct that merged with the common bile duct was found, and a double bilio-intestinal anastomosis was performed.

DISCUSSION

Definition of accessory hepatic duct, requires the existence of a main right hepatic duct, otherwise the definition of "accessory" is inconclusive. In our case the accessory right hepatic duct drained the posterior segments of the right hepatic lobe.

CONCLUSION

A detailed mapping of the biliary tree is essential in patients that will undergo major interventions of the hepatobiliary system. Common and rare variations of the biliary tree should be known prior to any intervention to avoid intraoperative difficulties or complications.

Biliary reconstructive techniques and associated anatomic variants in adult living donor liver transplantations: The adult-to-adult living donor liver transplantation cohort study experience

Living donor liver transplantation (LDLT) is a technically demanding endeavor, requiring command of the complex anatomy of partial liver grafts. We examined the influence of anatomic variation and reconstruction techniques on surgical outcomes and graft survival in the 9-center Adult-to-Adult Living Donor Liver Transplantation Cohort Study (A2ALL). Data from 272 adult LDLT recipients (2011-2015) included details on anatomic characteristics and types of intraoperative biliary reconstruction. Associations were tested between reconstruction technique and complications, which included first biliary complication (BC; leak, stricture, or biloma) and first vascular complication (VC; hepatic artery thrombosis [HAT] or portal vein thrombosis [PVT]). Time to patient death, graft failure, and complications were estimated using Kaplan-Meier curves and tested with log-rank tests. Median posttransplant follow-up was 1.2 years. Associations were found between the type of biliary reconstruction and the incidence of VC (P = 0.03) and BC (P = 0.05). Recipients with Roux-en-Y hepaticojejunostomy had the highest probability of VC. Recipients with biliary reconstruction involving the use of high biliary radicals on the recipient duct had the highest likelihood of developing BC (56% by 1 year) compared with duct-to-duct (42% by 1 year). In conclusion, the varied surgical approaches in the A2ALL centers offer a novel opportunity to compare disparate LDLT approaches. The choice to use higher biliary radicals on the recipient duct for reconstruction was associated with more BC, possibly secondary to devascularization and ischemia. The use of Roux-en-Y biliary reconstruction was associated with VCs (HAT and PVT). These results can be used to guide biliary reconstruction decisions in the setting of anatomic variants and inform further improvements in LDLT reconstructions. Ultimately, this information may contribute to a lower incidence of technical complications after LDLT. Liver Transplantation 23 1519-1530 2017 AASLD.

Rare anatomic variation of the right hepatic artery and accessory right hepatic artery supplying hepatocellular carcinoma: A case report and literature review

INTRODUCTION

Each hepatic artery is functionally essential for providing blood supply to the liver, and so are variant arteries. Variant arteries, including the accessory right hepatic artery (ARHA) and replaced right hepatic artery (RRHA) are commonly described in the literature. However, they usually occur independently. Here, we report an extremely rare case that involved both an ARHA and an RRHA arising from the gastroduodenal artery (GDA) and superior mesenteric artery (SMA), respectively. To date, this situation has never been reported in the literature.They were preoperatively identified during magnetic resonance imaging (MRI) examination in a 69-year-old male patient with hepatocellular carcinoma. And they were further verified by following conventional angiography for transcatheter arterial chemoembolization (TACE) for the patient. In addition, the patient's tumor was primarily supplied by these 2 variant arteries. After the successful TACE procedure, the patient had a well postoperative recovery.

CONCLUSIONS

By analyzing this case and performing a systematic review of the literature, the important clinical implications of the ARHA and RRHA will be investigated and discussed. Main lessons learned from this case thorough understanding of the normal anatomy of the hepatic artery and its anatomic variation is crucial for surgeons and interventional radiologists; preoperative computed tomography, MRI, and intraoperative angiography play an important role in detecting the variant hepatic artery; identifying these anomalous hepatic arteries before operation can effectively avoid unintentional injury during surgery, such as massive hemorrhage or hepatic infarction.

Pure laparoscopic donor right hepatectomy in a living donor with type 3a biliary variation: A case report

RATIONALE

With refinements in the operative technique, laparoscopic surgery has become the standard practice for liver resection. In the field of living donor liver transplantation, a few centers adopted laparoscopic surgery as an alternative to conventional open donor hepatectomy, and the application of pure laparoscopic donor right hepatectomy has been limited to the donors with simple, favorable biliary anatomy.

PATIENT CONCERNS

The candidate donor was a 19-year-old woman with type 3a bile duct variation.

INTERVENTIONS

After confirming precise cutting points under the guidance of a radiopaque marker rubber band, the bile ducts were divided and the remnant stumps were closed with suture and clipping using Hem-o-lok, respectively.

OUTCOMES

The postoperative course was uneventful and she was satisfactory 6 months after surgery.

LESSONS

A laparoscopic donor hepatectomy for the living donor with biliary variation was feasible. Biliary variations are commonly encountered during living donor surgery, and we think that such variations in laparoscopic donor hepatectomy need to be overcome to expand the selection criteria.

Reconstruction of Anomalous Portal Venous Branching in Right Lobe Living Donor Liver Transplantation: Malatya Approach

Reconstruction of anomalous portal vein branching (APVB) during right lobe living donor liver transplantation (LDLT) can be challenging. The goal of this article is to describe our surgical technique, named the Malatya Approach, in case of APVB during right lobe LDLT. The technique unifies the APVB and obtains a funnel-shaped common extension with a circumferential fence by a saphenous vein conduit. In total, 126 (10.6%) of 1192 right lobe grafts had APVB that were divided into 2 groups according to the adopted surgical techniques: the Malatya Approach group (n = 91) and the previously defined other techniques group (n = 35). Both groups were compared regarding portal vein thrombosis (PVT), postoperative 90-day mortality and survival. PVT developed in 3 patients (3.3%) in the Malatya Approach group and developed in 10 (28.6%) patients for the other group (P < 0.001). There were 8 (8.8%) 90-day mortalities in the Malatya Approach group (1 PVT related) and 15 patients (9 PVT related) died in the other techniques group (P < 0.001). Mean follow-up time for both groups was similar (999.1 days for the Malatya Approach group versus 1024.7 days for the other group; P = 0.47), but longterm survival in the Malatya Approach group was better than in the other group (84.6% versus 40%; P < 0.001). Multivariate analysis revealed that the Malatya Approach group showed less PVT development and longer survival (P < 0.001). This technique is promising to avoid PVT and mortalities in cases of APVB during right lobe LDLT. Liver Transplantation 23 751-761 2017 AASLD.

Magnetic resonance cholangiopancreatography evaluation of intrahepatic bile duct variations with updated classification

PURPOSE

Preoperative detection of intrahepatic bile duct (IHBD) variations is essential to reduce surgical morbidity and mortality rates. Magnetic resonance cholangiopancreatography (MRCP) is a noninvasive and reliable method for demonstrating the normal IHBD anatomy and its variations. This retrospective study aimed to identify and classify novel variations, except those already reported in the literature, using MRCP.

METHODS

MRCP examinations, which were conducted in two different centers in the last five years, were retrospectively evaluated. IHBD variations were recorded with respect to the Yoshida classification. In addition, newly detected variations that were not included in this classification were identified and classified.

RESULTS

MRCP examinations of 2624 patients were screened, and 2143 were determined to be eligible for evaluation. Of 2143 patients, 987 were males (average age, 54±18 years) and 1156 were females (mean age, 57±17 years). In this study, 10 novel variations that were not included in the Yoshida classification were identified in 14 patients.

CONCLUSION

MRCP is an effective, reliable, and noninvasive imaging method for evaluating the IHBD anatomy and its variations. Novel variations described in this study may help to better understand the biliary anatomy.

Preoperative evaluation of accessory hepatic ducts by drip infusion cholangiography with CT

BACKGROUND

This retrospective study aimed to investigate the incidence of each type of accessory hepatic duct by drip infusion cholangiography with CT (DIC-CT).

METHODS

Five hundred sixty nine patients who underwent preoperative DIC-CT and laparoscopic cholecystectomy were reviewed. Accessory hepatic ducts were classified as follows: type I (accessory hepatic ducts that merged with the common hepatic duct between the confluence of the right and left hepatic ducts and the cystic duct confluence), type II (those that merged with the common hepatic duct at the same site as the cystic duct), type III (those that merged with the common bile duct distal to the cystic duct confluence), type IV (the cystic duct merged with the accessory hepatic duct), and type V (accessory hepatic ducts that merged with the common hepatic or bile duct on the left side).

RESULTS

Accessory hepatic ducts were observed in 50 patients. Type I, II, III, IV, and V accessory hepatic ducts were detected in 32, 3, 1, 11, and 3 patients, respectively. Based on their drainage areas, the accessory hepatic ducts were also classified as follows: a posterior branch in 22 patients, an anterior branch in 9 patients, a combination of posterior and anterior branches in 16 patients, a left-sided branch in 2 patients, and a caudate branch in 1 patient. None of the patients with accessory hepatic ducts suffered bile duct injuries.

CONCLUSION

There are a number of variants of the accessory hepatic duct. DIC-CT is useful to detect the accessory hepatic duct.

The Preliminary Study on Procurement Biliary Convergence from Donors with Complicated Bile Duct Variant in Emergency Right Lobe Living Donor Liver Transplantation

BACKGROUND

The incidence of biliary complications after living donor adult liver transplantation (LDALT) is still high due to the bile duct variation and necessity reconstruction of multiple small bile ducts. The current surgical management of the biliary variants is unsatisfactory. We evaluated the role of a new surgical approach in a complicated hilar bile duct variant (Nakamura type IV and Nakamura type II) under emergent right lobe LDALT for high model for end-stage liver disease score patients.

METHODS

The common hepatic duct (CHD) and the left hepatic duct (LHD) of the donor were transected in a right-graft including short common trunks with right posterior and anterior bile ducts, whereas the LHD of the donor was anastomosed to the CHD and the common trunks of a right-graft bile duct and the recipient CHD was end-to-end anastomosed.

RESULTS

Ten of 13 grafts (Nakamura types II, III, and IV) had two or more biliary orifices after right graft lobectomy; seven patients had biliary complications (53.8%). Later, the surgical innovation was carried out in five donors with variant bile duct (four Nakamura type IV and one type II), and, consequently, no biliary or other complications were observed in donors and recipients during 47-53 months of follow-up; significant differences (P < 0.05) were found when two stages were compared.

CONCLUSION

Our initial experience suggests that, in the urgent condition of LDALT when an alternative live donor was unavailable, a surgical innovation of cutting part of the CHD trunks including variant right hepatic ducts in a complicated donor bile duct variant may facilitate biliary reconstruction and reduce long-term biliary complications.

Replaced right and left hepatic arteries: a variation in origin and course

In ∼60% of cases, hepatic artery anatomy is of the normal variant. However, in 40% of cases, anomalies can exist. Preserving the hepatic blood supply is paramount in hepatobiliary procedures. We report an aberrant right hepatic artery coursing retroportally, with an aberrant left hepatic artery originating directly from the coeliac artery in a patient who underwent an elective pancreaticoduodenectomy (Whipple procedure).

Adult to adult right lobe living donor liver transplantation: does biological relationship matter?

The influence of the biological relationship between the donor and the recipient is rarely discussed in living donor liver transplantation (LDLT), although it is believed to be an important risk factor in other types of organ transplantations. A total of 272 consecutive patients undergoing adult to adult right lobe LDLT were retrospectively analyzed and stratified into a nonbiologically related (NBR) group (69 patients) and a biologically related (BR) group (203 patients). The preoperative data and postoperative outcomes of both recipients and donors were evaluated.More than two-thirds of the recipients had histories of HBV infection, and hepatocellular carcinoma (HCC) was the main reason for the patients undergoing LDLT in both groups. The percentage of female donors in the NBR group was more than the percentage in the BR group (P = 0.000). There were no differences between the groups in postoperative laboratory testing or daily immunosuppression dose, and the complication rates in both the recipient and donor surgeries showed no significant differences. For patients with benign diseases, the cumulative 1-, 3-, 5-, and 10-year survival rate were 92.9% in the 4 periods in the NBR group and 89.1%, 87.6%, 83.7%, and 83.7%, respectively, in BR group, while for the patients diagnosed as HCC, if patients exceeding the Milan criteria were involved, the 5-year survival rate was 41.2%, compared to 82% for patients within the Milan criteria, which was nearly the same as for those with the benign disease. In conclusion, our findings suggested that the biological relationship between the donor and the recipient in adult to adult LDLT was not associated with the short- and long-term outcomes of recipients diagnosed with benign liver diseases and early stage HCC. Moreover, the criteria for patients diagnosed with HCC to undergo LDLT should be restrictively selected.

Genetic Traits in the Liver Anatomy Between Parents and Children: An Analysis of Liver Transplant Recipients and Living Donors

BACKGROUND

To date, no significant similarities in the anatomy of the hepatic vasculature have been observed between blood-related individuals. However, we have frequently encountered anatomic similarities between parents and their children; thus, we performed an analysis of the genetic traits in the anatomy of the liver.

METHODS

The study cohort was 330 adult cases of living-donor liver transplantation (LDLT), in which the donor-recipient relationship was child to parent. The subjects underwent LDLT from January 2013 to December 2014. Preoperative dynamic computerized tomographic scans were used to classify the anatomy of the hepatic vasculature.

RESULTS

Portal vein (PV) anatomy was classified as typical and 2 variant types. PV anatomy combinations in donor and recipient were typical in 232 subjects, variant in 16, and typical-variant in 82. The PV concordance rate was 75.2%, and the contingency coefficient was 0.130 (P = .017). Hepatic artery (HA) anatomy was classified as typical and 4 variant types. HA anatomy combinations in donor and recipient were typical in 167 subjects, variant in 33, and typical-variant in 130. The HA concordance rate was 60.6%, and the contingency coefficient was 0.058 (P = .294). The sizable inferior right hepatic vein in donor and recipient was present in 44 subjects, absent in 160, and discordant in 126; its concordance rate was 61.8% and contingency coefficient 0.133 (P = .014).

CONCLUSIONS

There may be a shared but weak genetic trait between parents and children regarding the anatomy of the PV and inferior hepatic vein. This information may be helpful when LDLT is performed between 1st-degree relatives.