Correlation between portal vein anatomy and bile duct variation in 407 living liver donors

Clinical implications of aberrant anatomy of the common hepatic duct in liver surgery: a systematic review and meta-analysis

INTRODUCTION

Knowledge of anatomical variants that affect the hepatic duct (HD) are of particular clinical relevance during hepatobiliary surgical procedures. More specifically, the aberrant anatomy of the common HD is the most common anatomical variation affecting the biliary tree. Below, we describe different classifications of anatomical variants that affect this canal. According to Huang's classification, variations are determined depending on the insertion of the right posterior hepatic duct (RPHD).

MATERIALS AND METHODS

Medline, Scopus, Web of Science, Google Scholar, CINAHL, and LILACS databases were investigated until January 2024. The methodological quality was assessed with an anatomical studies assurance tool (AQUA). Pooled prevalence was estimated using a random effects model. For the subgroup analysis, Student's T-test was used.

RESULTS

The prevalence rate of aberrant hepatic duct (AHD) was 15% (confidence interval [CI] of 7-22%). The first subgroup had cadavers and images. For the cadavers, the prevalence was 15.83% (CI: 11.22-18.3%), while the images had a prevalence of 22.06% (CI: 18.12-25.33%). This subgroup analysis showed no statistically significant difference between these groups (p = 0.127). The second subgroup comprised the continents where the included studies were from. In this subgroup, no statistically significant differences were found (p = 0.613). Finally, regarding the right or left laterality of the HD variant, there were no statistically significant differences (p = 0.089).

CONCLUSION

A AHD corresponds to a finding that can occur in a significant percentage of our society, which could be an accidental discovery during surgeries or present asymptomatically throughout life and be a cadaveric discovery later. We believe it is important for surgeons to have prior knowledge of the possible variants of HD to prevent possible complications during and after surgery.

Asian Pacific Association for the Study of the Liver clinical practice guidelines on liver transplantation

Liver transplantation is a highly complex and challenging field of clinical practice. Although it was originally developed in western countries, it has been further advanced in Asian countries through the use of living donor liver transplantation. This method of transplantation is the only available option in many countries in the Asia-Pacific region due to the lack of deceased organ donation. As a result of this clinical situation, there is a growing need for guidelines that are specific to the Asia-Pacific region. These guidelines provide comprehensive recommendations for evidence-based management throughout the entire process of liver transplantation, covering both deceased and living donor liver transplantation. In addition, the development of these guidelines has been a collaborative effort between medical professionals from various countries in the region. This has allowed for the inclusion of diverse perspectives and experiences, leading to a more comprehensive and effective set of guidelines.

Pre-operative assessment of living liver donors' liver anatomy and volumes

Decades of experience supports LDLT as a favorable strategy to reduce waitlist mortality. The multiple regenerative pathways of hepatocytes and other hepatic cells justify the rationale behind it. Nonetheless, living liver donation is still underused and its broader implementation is challenging, mostly due to variability in practices leading to concerns related to donor safety. A non-systematic literature search was conducted for peer-reviewed original articles related to pre-operative evaluation of living liver donor candidates. Eligible studies were synthesized upon consensus for discussion in this up-to-date review. Review of the literature demonstrate that the importance of preoperative assessment of vascular, biliary and liver volume to ensure donor safety and adequate surgical planning for graft procurement is widely recognized. Moreover, data indicates that anatomic variants in vascular and biliary systems in healthy donors are common, present in up to 50% of the population. Therefore, comprehensive mapping and visualizations of each component is needed. Different imaging modalities are reported across practices and are discussed in detail. Lastly, assessment of liver volume must take into account several technical and donor factors that increase the chances of errors in volume estimation, which occurs in up to 10% of the cases. Experience suggests that maximizing donor safety and lessening their risks is a result of integrated experience between hepatobiliary and transplant surgery, along with multidisciplinary efforts in performing a comprehensive pre-operative donor assessment. Although technical advances have increased the accuracy of volume estimation, over- or under-estimation remains a challenge that needs further attention.

Aborted living-donor liver transplantation in the real-world setting, lessons from 13 937 cases of Vanguard Multi-center Study of International Living Donor Liver Transplantation Group

There are exceedingly uncommon but clearly defined situations where intraoperative abortions are inevitable in living-donor liver transplantation (LDLT). This study aimed to summarize the cases of aborted LDLT and propose a strategy to prevent abortion or minimize donor damage from both recipient and donor sides. We collected data from a total of 43 cases of aborted LDLT out of 13 937 cases from 7 high-volume hospitals in the Vanguard Multi-center Study of the International Living Donor Liver Transplantation Group and reviewed it retrospectively. Of the 43 cases, there were 24 recipient-related abortion cases and 19 donor-related cases. Recipient-related abortions included pulmonary hypertension (n = 8), hemodynamic instability (n = 6), advanced hepatocellular carcinoma (n = 5), bowel necrosis (n = 4), and severe adhesion (n = 1). Donor-related abortions included graft steatosis (n = 7), graft fibrosis (n = 5), primary biliary cholangitis (n = 3), anaphylactic shock (n = 2), and hemodynamic instability (n = 2). Total incidence of aborted LDLT was 0.31%, and there was no remarkable difference between the centers. A strategy to minimize additional donor damage by delaying the donor's laparotomy or trying to open the recipient's abdomen with a small incision should be effective in preventing some causes of aborted LDLT, such as pulmonary hypertension, advanced cancer, and severe adhesions.

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.

Right posterior bile duct stricture after laparoscopic anterior sectionectomy with long right bile duct: A case report

Right anterior liver sectionectomy (RAS) is a complicated procedure with high incidences of postoperative complications. We report a case of right posterior bile duct (RPBD) stricture after laparoscopic RAS with discussion of the anatomical aspects. A 69-year-old Japanese man had solitary colorectal liver metastasis. A tumor was located near the root of the right anterior Glissonean pedicle. On postoperative day 6, he had cholangitis and imaging studies showed RPBD stricture. Symptoms disappeared following a course of antibiotics and the patient was discharged on postoperative day 21. The RBPD anatomy type of this patient was a supra-portal pattern with a long (18 mm) right biliary duct, which would be close to the right anterior Glissonean bifurcation. A stapling device might have caused its deformation and resulted in its stricture. As the RPBD has variant anatomy, we had to notice that there may be hazardous types for postoperative RPBD stricture.

Comparison of surgical outcomes and learning curve for robotic versus laparoscopic living donor hepatectomy: A retrospective cohort study

BACKGROUND

Both laparoscopic living donor right hemihepatectomy (LLDRH) and robotic living donor right hemihepatectomy (RLDRH) have been developed for minimally invasive donor hepatectomy (MIDH), although comparative analysis between the two surgical modalities is lacking. This study aims to compare surgical outcomes of LLDRH and RLDRH at a single institution.

MATERIALS AND METHODS

From March 2016 to March 2022, 171 patients who underwent MILH of right liver were enrolled and divided into RLDRH and LLDRH. Two surgeons with experience in both techniques performed all procedures. Clinical characteristics, perioperative outcomes of donor and recipient, and donor anatomic variations were compared between both groups, and learning curves were estimated. Subgroup analysis was also performed, including only donors recruited after 2019, when LLDRH was initiated at our institution.

RESULTS

RLDRH and LLDRH were performed for 102 and 69 patients, respectively. Operative time was significantly longer for RLDRH than LLDRH (464 vs. 407 min, P < 0.001), although estimated blood loss was lower in RLDRH (104 vs. 238 mL, P = 0.002). Incidence of major complications was similar in both groups. After 2019, significantly more RLDRH vs. LLDRH patients had variation in the hepatic artery (14.3% vs. 2.9%, P = 0.020) and portal vein (16.1% vs. 4.3%, P = 0.027). Learning curve for RLDRH was stabilized after approximately the 16th case, whereas that of LLDRH stabilized immediately.

CONCLUSION

RLDRH resulted in less intraoperative bleeding and comparable postoperative outcomes than LLDRH. Moreover, since 2019, RLDRH has been employed more frequently for donors with hilar structure anatomic variations. Based on our single-center experience, we propose that standardized procedures for RLDRH might help set up pure minimally invasive procedures for donor hepatectomy and facilitate safe implementation of laparoscopic approaches.

Laparoscopic central hepatectomy using a parenchymal-first approach: how we do it

BACKGROUND

Laparoscopic central hepatectomy (LCH) is a difficult and challenging procedure. This study aimed to describe our experience with LCH using a parenchymal-first approach.

METHODS

Between July 2017 and June 2021, 19 consecutive patients underwent LCH using a parenchymal-first approach at our institution. Herein, the details of this procedural strategy are described, and the demographic and clinical data of the included patients were retrospectively analyzed.

RESULTS

There were 1 female and 18 male patients, all with hepatocellular carcinoma without major vascular invasion. The mean age was 57 ± 10 years. No patients underwent conversion to open surgery, and no blood transfusions were needed intraoperatively. The average operative duration and the average Pringle maneuver duration were 223 ± 65 min and 58 ± 11 min. respectively. The median blood loss was 200 ml (range: 100-800 ml). Postoperative morbidities occurred in 3 patients (15.8%), including 2 cases of bile leakage and 1 case of acquired pulmonary infection; there were no postoperative complications happened such as bleeding, hepatic failure, or mortality. The average postoperative hospital stay was 10 ± 3 days.

CONCLUSION

The optimized procedure of LCH using a parenchymal-first approach is not only feasible but also expected to provide an advantage in laparoscopic anatomical hepatectomy.

Living liver donor hilar anatomical variations and impact of variant anatomy on transplant outcomes

Donor anatomy is an essential part of donor selection and operative planning in living donor liver transplantation. In this study, variations of hilar structures, and the effects of variant anatomy on donor and recipient outcomes were evaluated. Living donor liver transplantations in a single center between January 2013 and December 2020 were retrospectively reviewed. In total, 203 liver transplantations were analyzed. Type 1 arterial anatomy, type 1 portal vein anatomy and type 1 bile duct anatomy were observed in 144 (70.9%), 173 (85.2%), and 129 (63.5%) donors, respectively. Variant biliary anatomy was observed more frequent in donors with variant portal vein branching than in those with type 1 portal anatomy (60.0% vs 32.3%, P = .004). The overall survival rates calculated for each hilar structure were similar between recipients receiving grafts with type 1 anatomy and those receiving grafts with variant anatomy. When donors with variant anatomy and donors with type 1 anatomy were compared in terms of hilar structure, no significant difference was observed in the frequency of complications and the frequency of serious complications. Biliary variations are more common in individuals with variant portal vein anatomy. Donor anatomic variations are not risk factors for inferior results of recipient survival or donor morbidity.

Leberchirurgie 4.0 - OP-Planung, Volumetrie, Navigation und Virtuelle Realität

Durch die Optimierung der konservativen Behandlung, die Verbesserung der bildgebenden Verfahren und die Weiterentwicklung der Operationstechniken haben sich das operative Spektrum sowie der Maßstab für die Resektabilität in Bezug auf die Leberchirurgie in den letzten Jahrzehnten deutlich verändert.

Dank zahlreicher technischer Entwicklungen, insbesondere der 3-dimensionalen Segmentierung, kann heutzutage die präoperative Planung und die Orientierung während der Operation selbst, vor allem bei komplexen Eingriffen, unter Berücksichtigung der patientenspezifischen Anatomie erleichtert werden.

Neue Technologien wie 3-D-Druck, virtuelle und augmentierte Realität bieten zusätzliche Darstellungsmöglichkeiten für die individuelle Anatomie. Verschiedene intraoperative Navigationsmöglichkeiten sollen die präoperative Planung im Operationssaal verfügbar machen, um so die Patientensicherheit zu erhöhen.

Dieser Übersichtsartikel soll einen Überblick über den gegenwärtigen Stand der verfügbaren Technologien sowie einen Ausblick in den Operationssaal der Zukunft geben.

A Novel Technique for Bile Duct Division During Laparoscopic Living Donor Hepatectomy to Overcome Biliary Complications in Liver Transplantation Recipients: "Cut and Clip" Rather Than "Clip and Cut"

BACKGROUND

This study was designed to analyze the clinical impact of a new bile duct division technique during laparoscopic living donor hepatectomy.

METHODS

Laparoscopic donor right hepatectomies performed by a single surgeon between December 2016 and August 2019 were included. Magnetic resonance cholangiopancreatography of the donors was reconstructed, and the length of the common channel of the dividing intrahepatic duct was measured. Patients were divided into 2 groups based on the bile duct division techniques of "clip and cut" versus "cut and clip." Outcome of bile duct division was categorized based on the graft and bile duct type and number of bile duct openings.

RESULTS

A total of 147 transplantations were included. Outcomes in the "cut and clip" group were better than those in the "clip and cut" group with regard to obtaining an adequate division point (94.2% versus 78.8%; P = 0.019). The "cut and clip" showed superior biliary stricture-free survival than the "clip and cut" group (hazard ratio [HR], 0.456; confidence interval [CI], 0.217-0.957; P = 0.038) whereas recipients with hepaticojejunostomy (HR, 3.358; CI, 1.090-10.350; P = 0.035) and bile duct type other than type I (HR, 2.214; CI, 1.143-4.289; P = 0.018) showed increased risk for biliary stricture-free survival. Better outcome in terms of obtaining a single opening was also obtained in the "cut and clip" group (68.2% versus 84.6%; P = 0.040), and this difference was significant especially with a common channel shorter than 10 mm (45.5% versus 81.2%; P = 0.043).

CONCLUSIONS

The "cut and clip" technique showed superior outcomes to the "clip and cut" technique in terms of fewer bile duct openings and biliary stricture-free survival of the recipients.

Congenital web of the common bile duct combined with multiple intrahepatic duct stricture: a report of successful radiological intervention

Congenital web formations are extremely rare anomalies of the extrahepatic biliary tree. We herein report a case of common bile duct septum combined with multiple intrahepatic bile duct strictures in a 74-year-old female patient who was successfully treated with radiological intervention. The patient initially visited the hospital because of upper abdominal pain. Imaging studies revealed multifocal strictures with dilatation in both intra- and extrahepatic ducts; the final clinical diagnosis was congenital common bile duct web combined with multiple intrahepatic duct strictures. Surgical treatment was not indicated because multiple biliary strictures were untreatable, and the disease was clinically diagnosed as benign. The multiple strictures were extensively dilated twice through bilateral percutaneous transhepatic biliary drainage (PTBD) for 2 months. After 1 month of observation, PTBD catheters were successfully removed. The patient is doing well at 6 months after completion of the radiological intervention, with the maintenance of normal liver function. Congenital web of the bile duct is very rare, and its treatment may vary depending on the patterns of biliary stenosis. In cases where surgical intervention is not indicated for congenital web and its associated disease, radiological intervention with balloon dilatation can be a viable therapeutic option.

Comparative anatomo-radiological study of intrahepatic venous vascularization in the Spain

BACKGROUND

Anatomic variations in the hepatic venous system are the least understood aspect of hepatic anatomy. The variations are diverse, and data are lacking with respect to the population of Spain and methods of detection. The objective was to examine morphological patterns of variations in hepatic venous vascularization using cadaveric dissections vs. radiological imaging, and to analyze the findings with respect to Spain and to published studies.

METHODS

Thirty-one livers were anatomically dissected and analyzed for their hepatic venous anatomy and then compared to the venous anatomy of livers examined in 216 CT scans from 119 men and 97 women, ranging between 27 and 89 years of age. Statistical analysis was done using the Chi squared and Fisher homogeneity tests.

RESULTS

The hepatic portal vein showed morphological variations in cadavers vs. CT of 67.3% vs. 67.6% (p-I), 29% vs. 12.2% (p-II), 0% vs. 14.6% (p-III), 0% vs. 14.6% (p-IV), 3.2% vs. 0.5% (p-V) and 6.5% vs. 1.9% (p-VI), respectively in cadavers vs. CT. Hepatic vein pattern variation were found in 64.5% vs. 50.7% (h-I), 32.2% vs. 31.5% (h-II), 0% vs. 2.3% (h-III), 0% vs. 4.7% (h-IV), respectively in dissections vs. CT). In Accessory Hepatic Veins the frequency in pattern variation was 64.5% vs. 18.8% (a-2.1), 29.0% vs. 8.0% (a-2.2), 58.1% vs. 11.3% (a-2.3), 9.7% vs. 0.9% (a-2.4), 67.7% vs. 16.9% (a-2.5), 9.7% vs. 4.2% (a-2.6) and 0% vs. 0.5% (a-2.7), respectively, in cadavers vs. CT. CT showed in 27.2% no accessory hepatic veins. Sex was not a factor influencing patterns of variation.

CONCLUSION

Anatomical variants of the hepatic portal vein, the hepatic vein and accessory hepatic veins are very diverse and show greater variability in the specimens compared to those detected with radiological images, finding a wider spectrum of variations as it allows the clinician to have a more precise definition of the vasculature. A higher precision in the definition of anatomical variations is warranted for surgical planning in liver resection and transplantation.

Postoperative outcomes of purely laparoscopic donor hepatectomy compared to open living donor hepatectomy: a preliminary observational study

Purpose

To lessen the physical, cosmetic, and psychological burden of donors, purely laparoscopic donor hepatectomy (PLDH) has been proposed as an ideal method for living donors. Our study aimed to prospectively compare the effect of PLDH and 2 other types of open living donor hepatectomy (OLDH) on postoperative pain and recovery.

Methods

Sixty donors scheduled to undergo donor hepatectomy between March 2015 and November 2017 were included. Donors were divided into 3 groups by surgical technique: OLDH with a subcostal incision (n = 20), group S; OLDH with an upper midline incision (n = 20), group M; and PLDH (n = 20), group L. The primary outcomes were postoperative pain and analgesic requirement during postoperative day (POD) 3. Other variables regarding postoperative recovery were also analyzed.

Results

Although pain relief during POD 3, assessed by visual analog scale (VAS) score and analgesic requirement, was similar among the 3 groups, group L showed lower VAS scores and opioid requirements than group M. Moreover, group L was associated with a rapid postoperative recovery evidenced by the shorter hospital length of stay and more frequent return to normal activity on POD 30.

Conclusion

This pilot study failed to verify the hypothesis that PLDH reduces postoperative pain. PLDH did not reduce postoperative pain but showed faster recovery than OLDH.

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.

Right hepatic venous system variation in living donors: a three-dimensional CT analysis

BACKGROUND

The right hepatic venous system consists of the right hepatic vein (RHV) and inferior RHVs (IRHVs). When the right posterior section is used as a graft for liver transplantation, understanding variations and relationships between the RHV and IRHVs is critical for graft venous return and hepatic vein reconstruction. This study aimed to evaluate variations in the hepatic veins and the relationships between them.

METHODS

The medical records and CT images of patients who underwent hepatectomy as liver donors were assessed retrospectively. The relationship between the veins was evaluated by three-dimensional CT.

RESULTS

The configuration of the posterior section was classified into one of eight types based on the RHV and IRHVs in 307 patients. Type 1a (103 of 307), type 1b (139 of 307) and type 2a (40 of 307) accounted for 91·9 per cent of the total. The diameter of the RHV extending towards the inferior vena cava had a significant inverse correlation with that of the IRHV (r²  = -0·615, P < 0·001). Type 1a, which had no IRHVs, had the RHV with the largest diameter; conversely, type 2a, which had a large IRHV, had the RHV with the smallest diameter.

CONCLUSION

The hepatic venous system of the right posterior section was classified into eight types, with an inverse relationship between RHV and IRHV sizes. This information is useful for segment VII resection or when the right liver is used as a transplant graft.

[Surgical anatomy of the right portal vein]

OBJECTIVE

To study the features of surgical anatomy of intrahepatic segments of right portal vein.

MATERIAL AND METHODS

The results of 260 histological examinations including sectional (n=60) and clinical (n=200) surveys were analyzed. Anatomical analysis implied assessment of organometric characteristics including liver weight, length, width and thickness of right and left lobes, division angles of portal vein, the number of branches, length and diameter of the vessels. Clinical examination was based on analysis of splenoportograms and X-ray direct portal venograms. Patients were divided into three groups according to their body type (dolichomorphic, mesomorphic, brachymorphic).

RESULTS

Anatomical and clinical surveys confirmed the differences in metric characteristics of portal vascular system depending on the body type. There was medial angulation of the median fissure under 70-85º (78.0±3.4°) in dolichomorphic and mesomorphic patients. Right angle between the median fissure and lower liver surface was observed in brachymorphic subjects. Portal vein division into the branches of the first order to the right of the median fissure was found in 49 cases. Median or left-sided division was noted in other cases. In most cases (n=219), right portal vein dichotomously divided into the right paramedian and right lateral branches. Portal trifurcation was detected in 2.3% of cases, medial translocation of the right paramedian branch - in 1.1% of cases.

CONCLUSION

Right liver lobe surgery may be associated with certain technical difficulties due to variable anatomy of the right portal vein. Anatomical and atypical liver resections should be preceded by preoperative identification of individual anatomical variations of the main liver vessels. Contrast-enhanced computed tomography is optimal method for this purpose.

One-Year Recipient Morbidity of Liver Transplantation Using Pure Laparoscopic Versus Open Living Donor Right Hepatectomy: Propensity Score Analysis

Donor safety and graft results of pure laparoscopic living donor right hepatectomy (LLDRH) have previously been compared with those of open living donor right hepatectomy (OLDRH). However, the clinical outcomes of recipients at 1-year follow-up have never been accurately compared. We aimed to compare 1-year outcomes of recipients of living donor right liver transplantation (LRLT) using pure LLDRH and OLDRH. From May 2013 to May 2017, 197 consecutive recipients underwent LRLT. Donor hepatectomies were performed either by OLDRH (n = 127) or pure LLDRH (n = 70). After propensity score matching, 53 recipients were included in each group for analysis. The clinical outcomes at 1-year follow-up were compared between the 2 groups. The primary outcome was recipient death or graft failure during the 1-year follow-up period. In the propensity-matched analysis, the incidence of death or graft failure during the 1-year follow-up period was not different between the 2 groups (3.8% versus 5.7%; odds ratio [OR], 1.45; 95% confidence interval [CI], 0.24-8.95; P = 0.69). However, the composite of Clavien-Dindo 3b-5 complications was more frequent in the pure LLDRH group (OR, 2.62; 95% CI, 1.15-5.96; P = 0.02). In conclusion, although pure LLDRH affords a comparable incidence of fatal complications in recipients, operative complications may increase at the beginning of the program. The safety of the recipients should be confirmed to accept pure LLDRH as a feasible option.

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.

Laparoscopic Donor Hepatectomy for Adult Living Donor Liver Transplantation Recipients

Even after 2 decades of experience in laparoscopic hepatectomy, data on purely laparoscopic approach for donor hepatectomy in adult living donor liver transplantation (LDLT) are limited. We report our initial experience of a purely laparoscopic approach for donor hepatectomy for adult recipients to explore its potential application in the management of donors. We did a retrospective data analysis of 54 consecutive patients operated on between May 2013 and February 2015. There were 41 right, 10 extended right, and 3 left hepatectomies. The median operative time was 436 minutes (range 294-684 minutes), and warm ischemia time was 6 minutes (2-12 minutes). Estimated blood loss was 300 mL (10-850 mL), and none of the patients required intraoperative transfusion. Four cases were converted to open laparotomy. The major complication rate was 16.7%, and biliary complication was the most frequent cause. Patients with normal anatomy had a major complication rate of 9.3% as compared with 45.5% in patients with anatomic variations. All patients recovered, and there was no mortality. In conclusion, a purely laparoscopic donor hepatectomy for adult LDLT recipients seems to be a feasible option; with careful patient selection and when performed by experienced surgeons, it may afford results comparable to the open method.

Optimal Monochromatic Imaging of Spectral Computed Tomography Potentially Improves the Quality of Hepatic Vascular Imaging

Objective

To investigate the efficiency of spectral computed tomography (CT) optimal monochromatic images in improving imaging quality of liver vessels.

Materials and Methods

The imaging data of 35 patients with abdominal CT angiography were retrospectively analyzed. Hepatic arteries, portal veins, and hepatic veins were reconstructed with mixed energy (quality check, QC), 70 keV and optimal monochromatic mode. Comparative parameters were analyzed including CT value, image noise (IN), contrast-to-noise ratio (CNR), signal-to-noise ratio (SNR), and subjective qualitative analysis.

Results

The optimal monochromatic value for assessment of the common hepatic artery, portal vein, and hepatic vein ranged between 49 keV and 53 keV, with a mean of 51 keV. There were statistically significant differences (p < 0.001) among the optimal monochromatic, 70 keV and QC images with regards to the hepatic vascular CT value, IN, CNR, SNR, and subjective qualitative score. CNR of the common hepatic artery in the optimal monochromatic, 70 keV and QC groups was 24.6 ± 10.9, 18.1 ± 8.3, and 11.6 ± 4.6, respectively (p < 0.001) with subjective scores of 4.7 ± 0.2, 4.0 ± 0.3, and 3.6 ± 0.4, respectively (p < 0.001). CNR of the hepatic portal vein was 6.9 ± 2.7, 4.3 ± 1.9, and 3.0 ± 2.1, respectively (p < 0.001) with subjective scores of 4.5 ± 0.3, 3.9 ± 0.4, and 3.3 ± 0.3, respectively (p < 0.001). CNR of the hepatic vein was 5.7 ± 2.3, 4.2 ± 1.9, and 2.7 ± 1.4, respectively with subjective scores of 4.3 ± 0.3, 3.8 ± 0.4, and 3.2 ± 0.3, respectively (p < 0.001).

Conclusion

Optimal monochromatic images can lead to improvement in the imaging parameters and optimization of the image quality of the common hepatic artery, hepatic portal vein and hepatic vein compared with conventional mixed kV and with 70 keV datasets.

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.

Unusual Branching Pattern of the Portal Vein: Its Importance

Portal vein anatomy and its branching pattern are of utmost importance for surgical planning of complex liver resections, living donor liver transplant and radiological procedures. The division of the vein at the porta hepatis, into the right and left branches is the most common branching pattern. Various branching variations have been described. We report a previously undescribed branching pattern of the right portal vein, where the segment VII vein arises directly from the left portal vein.

Usefulness of 3D balanced turbo-field-echo MR sequence evaluating the branching pattern of the intrahepatic bile ducts: comparison with drip infusion CT cholangiography

PURPOSE

For liver surgery, it is crucial to preoperatively examine the course of the right posterior bile duct. While MR cholangiopancreatography (MRCP) can only visualize the bile ducts, 3D balanced turbo-field-echo (BTFE) sequence clearly depicts the bile ducts and portal veins as well as drip infusion CT cholangiography (DIC-CT), without contrast media. We evaluated whether BTFE could substitute for DIC-CT.

MATERIALS AND METHODS

Thirty patients undergoing MRCP and BTFE on 1.5-T MR and DIC-CT were evaluated. Two readers retrospectively evaluated the branching pattern (supra-type: A-C or infra-type: D-E) and scored the degree of confidence and motion artifacts using a 3-point scale for the three 2-mm-thick reconstructed images.

RESULTS

The bile duct diameter did not differ between DIC-CT and MRCP (p = 0.07). Five patients (17%) had intrahepatic biliary dilatation (>3 mm). The A, B, C, D, and E types were diagnosed in 21, 6, 1, 1, and 1 patient, respectively (28 supra-types and 2 infra-types) on DIC-CT. For DIC-CT, MRCP, and BTFE, the mean motion artifact scores were 3.0/3.0, 2.7/2.6, and 2.9/2.8, respectively. The mean diagnostic confidence scores were 2.9/2.9, 2.4/2.4, and 2.9/2.8, respectively, with no difference between DIC-CT and BTFE. The concordance between DIC-CT and BTFE was high (infra- or supra-type: κ = 1.00/1.00, A-E: κ = 0.86/0.66), but it was poor between DIC-CT and MRCP (infra- or supra-type: κ = 0.35/-0.05, A-E: κ = 0.33/0.41) for both readers.

CONCLUSIONS

Similar to DIC-CT, the BTFE MR sequence had high diagnostic accuracy regarding the branching pattern of the intrahepatic bile duct, especially for the supra/infraportal type.

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.

Clinical Implications of Biliary Confluence Pattern for Bismuth-Corlette Type IV Hilar Cholangiocarcinoma Applied to Hemihepatectomy

BACKGROUND

Since biliary variations are commonly seen, our aims are to clarify these insidious variations and discuss their surgicopathologic implications for Bismuth-Corlette (BC) type IV hilar cholangiocarcinoma (HC) applied to hemihepatectomy.

METHODS

Three-dimensional images of patients with distal bile duct obstruction (n = 97) and advanced HC (n = 79) were reconstructed and analyzed retrospectively. Normal biliary confluence pattern was defined as the peripheral segment IV duct (B4) joining the common trunk of segment II (B2) and segment III (B3) ducts to form the left hepatic duct (LHD) that then joined the right hepatic duct (RHD). The lengths from left and right secondary biliary ramifications to the right side of the umbilical portion of the left portal vein (Rl-L) and the cranio-ventral side of the right portal vein (Rr-R) were measured, respectively, and compared with the resectable bile duct length in HCs. Surgicopathologic findings were compared between different BC types.

RESULTS

The resectable bile duct length in right hemihepatectomy for eradication of type IV tumors was significantly longer than the Rl-L length in normal biliary configuration (17.4 ± 1.8 and 10.3 ± 3.4 mm, respectively, p < 0.001), and type III variation (B2 joining the common trunk of B3 and B4) was the predominant configuration (53.8%). The resectable length in left hemihepatectomy for eradication of type IV tumors was comparable with the Rr-R length in RHD absent cases (15.2 ± 2.5 and 16.4 ± 2.6 mm, respectively, p = 0.177) but significantly longer than that in normal configuration (p < 0.001). The estimated length was 8.5 ± 2.0 mm in unresectable cases. There was no significant difference between type III and IV tumors, except for the rate of nodal metastasis (29.7 and 76.0%, respectively, p < 0.001).

CONCLUSION

Hemihepatectomy might be selected for curative-intent resection of BC type IV tumors considering the advantageous biliary variations, whereas anatomical trisegmentectomy is recommended for the resectable bile duct length less than 10 mm. Biliary variations might result in excessive classification of BC type IV but require validation on further study.

Anatomic features of independent right posterior portal vein variants: Implications for left hepatic trisectionectomy

BACKGROUND

No authors have reported on the anatomic features of the independent right posterior portal vein variant and its relevance to left hepatic trisectionectomy. The purpose of this study was to review vasculobiliary systems according to portal vein anatomy, to clarify the anatomic features of the right posterior portal vein variant, and to discuss its operative implications for left hepatic trisectionectomy.

METHODS

In a radiologic study, the 3-dimensional anatomy of the portal vein, hepatic artery, and bile duct were studied in 200 patients who underwent computed tomography. In a surgical study, medical records were retrospectively reviewed for 463 patients who underwent hepatectomy for perihilar cholangiocarcinoma.

RESULTS

In the radiologic study, an independent right posterior portal vein variant was observed in 19 patients. The following observations were made in association with the portal vein variant: (1) a supraportal or combined type right posterior hepatic artery was never found; (2) an infraportal right posterior bile duct was observed at a significantly greater frequency than in patients with normal portal vein anatomy; and (3) the volume of the right posterior sector was significantly larger than in normal portal vein anatomy (37.4 ± 6.1% vs 27.3 ± 5.1%, P < .001). In the surgical study, the independent right posterior portal vein variant was observed in 41 (8.9%) patients. Of the 135 patients who underwent left hepatic trisectionectomy, 28 (20.7%) had this portal vein variant.

CONCLUSION

Independent right posterior portal vein variants exhibit anatomic features that are advantageous for performing left hepatic trisectionectomy.

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.