Hepatic venous drainage: how much can we learn from imaging studies? Anatomic-functional classification derived from three-dimensional computed tomography reconstructions

Quantitative anatomy of the large variant right hepatic vein: A systematic three-dimensional analysis

Anatomical variations of the right hepatic vein, especially large variant right hepatic veins (≥5 mm), have important clinical implications in liver transplantation and resection. This study aimed to evaluate anatomical variations of the right hepatic vein using quantitative three-dimensional visualization analysis. Computed tomography images of 650 patients were retrospectively analyzed, and three-dimensional visualization was applied using the derived data to analyze large variant right hepatic veins. The proportion of the large variant right hepatic vein was 16.92% (110/650). According to the location and number of the variant right hepatic veins, the configuration of the right hepatic venous system was divided into seven subtypes. The length of the retrohepatic inferior vena cava had a positive correlation with the diameter of the right hepatic vein (rs = 0.266, p = 0.001) and the variant right hepatic veins (rs = 0.211, p = 0.027). The diameter of the right hepatic vein was positively correlated with that of the middle hepatic vein (rs = 0.361, p < 0.001), while it was inversely correlated with that of the variant right hepatic veins (rs = -0.267, p = 0.005). The right hepatic vein diameter was positively correlated with the drainage volume (rs = 0.489, p < 0.001), while the correlation with the variant right hepatic veins drainage volume was negative (rs = -0.460, p < 0.001). The number of the variant right hepatic veins and their relative diameters were positively correlated (p < 0.001). The volume and percentage of the drainage area of the right hepatic vein decreased significantly as the number of the variant right hepatic vein increased (p < 0.001). The findings of this study concerning the variations of the hepatic venous system may be useful for the surgical planning of liver resection or transplantation.

Hepatic venous reconstruction of the left lateral segment with emphasis on anomalous hepatic vein in pediatric liver transplantation

Left lateral segment grafts have become a suitable option in pediatric liver transplantation (PLT). The correlation between hepatic vein (HV) reconstruction and outcome is relevant when assessing the safe use of these grafts. We retrospectively reviewed the medical records prospectively collected from a pediatric living donor liver transplantation database and conducted a comparative analysis of the different left lateral segment graft types according to HV reconstruction. Donor, recipient, and intraoperative variables were analyzed. Post-transplant outcomes included vascular complications such as hepatic vein outflow obstruction, early (≤30 d) and late (>30 d) PVT, hepatic artery thrombosis, and graft survival. From February 2017 to August 2021, 303 PLTs were performed. According to venous anatomy, the distribution of the left lateral segment was as follows: single HV (type I) in 174 (57.4%), close HVs, simple venoplasty for reconstruction (type II) in 97 (32.01%), anomalous hepatic vein (AHV) with a distance between the HVs orifices that allowed simple venoplasty (type IIIA) in 25 (8.26%) and AHV with a distance between the HVs orifices requiring homologous venous graft interposition (type IIIB) in 07 (2.31%) grafts. Type IIIB grafts came from male donors ( p =0.04) and had a higher mean donor height ( p =0.008), a higher mean graft weight, and a higher graft-to-recipient weight ratio, both p =0.002. The median follow-up time was 41.4 months. The overall cumulative graft survival was 96.3%, and comparative graft survival showed no difference (log-rank p =0.61). No hepatic vein outflow obstructions were observed in this cohort study. There was no statistically significant difference in the post-transplant outcomes between the graft types. The venous reconstruction of the AHV with homologous venous graft interposition had similar outcomes in the short and long term.

Transversal hepatectomies: Classification and intention-to-treat validation of new parenchyma-sparing procedures for deep-located hepatic tumors

BACKGROUND

Deep-located liver tumors involving hepatic veins at the caval confluence or main Glissonean pedicles generally require a major hepatectomy. An intraoperative ultrasound guidance policy opened a possibility to opt for parenchyma-sparing procedures as alternatives to major hepatectomy, called transversal hepatectomies. We ought to standardize the procedure and analyze the surgical outcome, oncological suitability, and salvageability.

METHODS

This is a retrospective cohort study. All consecutive patients undergoing hepatectomies for liver tumors between January 2005 and August 2020 were reviewed. Transversal hepatectomies were classified as follows: upper transversal hepatectomy: resection of the posterosuperior segments along with at least 1 hepatic vein and preservation of the anteroinferior ones; roller coaster hepatectomy: transversal hepatectomy with tumor vessel detachment from at least 2 hepatic veins; and lower transversal hepatectomy: amputation of the distal portion of at least 1 hepatic vein with tumor vessel detachment from first/second-order Glissonean pedicles. Morbidity, mortality, local recurrences, and salvageability in cases of relapse were considered.

RESULTS

A total of 61 transversal hepatectomies were performed: 40 (66%) upper transversal hepatectomies, 19 (31%) roller coaster hepatectomies, and 2 (3%) lower transversal hepatectomies. The median preserved liver volume was 67% (range 41-86). Mortality was 0, and major morbidity was 6%. Local recurrence occurred in 7 (11%) patients. Ten out of 34 (29%) patients with liver-only recurrence received redo surgery.

CONCLUSION

Transversal hepatectomies offer a new parenchyma-sparing perspective for the management of complex tumor presentation, which would otherwise demand major tissue removal or even unresectability. Safety, adequate local control, and salvageability are further pillars of this approach herein systematized.

Funneling venoplasty for anomalous graft left hepatic vein in living donor liver transplantation using a split left lateral section graft for an infant patient

The left lateral section (LLS) can have an unusual variant left hepatic vein (LHV) anatomy. We present a case of customized funneling venoplasty of the graft LHV in a 22-month-old girl diagnosed with ornithine transcarbamylase deficiency undergoing deceased donor liver transplantation (LT) using a split LLS graft. The split LLS graft weighed 350 g, yielding a graft-to-recipient weight ratio of 3.2%. Notably, the graft LHV opening was located at the graft liver cut surface, which was only 1 cm in size and 2 cm away from the cephalad apex of the LLS graft. Since such a variant location of the small LHV opening was unsuitable for direct anastomosis, we performed a funneling venoplasty using an inferior vena cava fragment homograft obtained from the same donor. The graft implantation was performed according to standard procedures of infant split LT. Follow-up imaging studies showed no vascular complications. The patient recovered uneventfully from the LT operation. She had normal blood test findings, including normal ammonia level. She has been doing well for 6 months after the transplantation. In conclusion, our surgical technique using a funneling venoplasty enabled successful reconstruction of the anomalous graft LHV. Our results suggest that individualized reconstruction techniques should be applied to infant patients undergoing LT using a LLS graft with variant types of graft LHV anatomy.

Current status of left lobe adult to adult living donor liver transplantation

PURPOSE OF REVIEW

This review describes the history and current state of left lobe living donor liver transplantation (LDLT). The transplant community continues to face an organ shortage on a global scale, and the expansion of LDLT is attractive because it allows us to provide life-saving liver transplants to individuals without drawing from, or depending on, the limited deceased donor pool. Donor safety is paramount in LDLT, and for this reason, left lobe LDLT is particularly attractive because the donor is left with a larger remnant.

RECENT FINDINGS

This article reviews the donor and recipient evaluations for left lobe LDLT, discusses small for size syndrome and the importance of portal inflow modification, and reviews recipient outcomes in right lobe versus left lobe LDLT.

SUMMARY

Left lobe LDLT was the first adult-to-adult LDLT ever to be performed in Japan in 1993. Since that time, the use of both right and left lobe LDLT has expanded immensely. Recent work in left lobe LDLT has emphasized the need for inflow modification to reduce portal hyperperfusion and early graft dysfunction following transplant. Accumulating evidence suggests, however, that even though early graft dysfunction following LDLT may prolong hospitalization, it does not predict graft or patient survival.

Perceptions of porta-celiac vascular models for hepatic surgery and their use in residency training

BACKGROUND

Primary aspect of hepatic navigation surgery is the identification of source vascular details to preserve healthy liver which has a vascular anatomy quite challenging for the young surgeons. The purpose was to determine whether three-dimensional (3D) vascular pattern models of preoperative computed tomography (CT) images will assist resident-level trainees for hepatic surgery.

METHODS

This study was based on the perception of residents who were presented with 5 different hepatic source vascular patterns and required to compare their perception level of CT, and 1:1 models in terms of importance of variability, differential of patterns and preoperative planning.

RESULTS

All residents agree that models provided better understanding of vascular source and improved preplanning. Five stations provided qualitative assessment with results showing the usefulness of porta-celiac models when used as anatomical tools in preplanning (p = 0.04), simulation of interventional procedures (p = 0.02), surgical education (p = 0.01). None of the cases had scored less than 8.5. Responses related to understanding variations were significantly higher in the perception of the 3D model in all cases, furthermore 3D models were more useful for seniors in more complex cases 3 and 5. Some open-ended answers: "The 3D model can completely change the operation plan" One of the major factors for anatomical resection of liver transplantation is the positional relationship between the hepatic arteries and the portal veins.

CONCLUSION

The plastic-like material presenting the hepatic vascularity enables the visualization of the origin, pattern, shape, and angle of the branches with appropriate spatial perception thus making it well-structured.

Venous hepatic segmentation in dogs (Canis lupus familiaris-L. 1758)

The external shape of the liver is varied and determines specific vascular arrangements. This morphological relationship is important to establish hepatic segmentation in different species submitted to surgeries that aim to preserve a larger area of liver parenchyma. After observing 60 livers injected with Neoprene Latex and three plastic moulds obtained by corrosion, eight hepatic venous segments were identified, drained by six hepatic veins agrouped into segmental veins, which drained one sector (segments I, VI, VII and VIII) and intersegmental veins, which drained more than one sector (segments II/III and IV/V). They were described as follows: left intersegmental vein, formed by a segmental vein from the papillary process (segment I), two to three lateral left segmental veins that drained the segment II, and one to five left paramedian segmental veins that drained the segment III; sagittal intersegmental vein, formed by the confluence between segmental vein of the quadrate lobe (segment IV) and the medial right paramedian segmental vein, which derived from the segment V; lateral right paramedian vein drained the dorsocranial sector of the segment VI; the lateral right segmental vein, formed by one to four vessels that drained segment VII, and the segmental vein of the caudate process, which drained the segment VIII. Understanding the number and disposition of the hepatic veins in lobate livers is essential to reduce bleeding risks in surgeries. The nomenclature based on segmentation analogy of non-lobate liver could be less confusing and, therefore, be more useful in the surgical approaches of lobate livers.

The influence of the middle hepatic vein and its impact on outcomes in right lobe living donor liver transplantation

BACKGROUND

In adult right lobe living donor liver transplantation, the decision to include the middle hepatic vein (MHV) remains controversial.

METHODS

A retrospective analysis of 50 R-LDLTs between January 2008 and June 2016 was performed.

RESULTS

Twenty-one procedures were performed using a MHV+ graft (42.0%) and 29 procedures using a MHV- graft (58%). MHV- donors were taller (173 vs 166 cm, p = 0.004) with a larger standard liver volume (1351 vs 1245 mls, p = 0.014) compared to MHV+ donors. The duration of operation for donors was significantly longer in the MHV+ group (530 (313-975) mins) compared to the MHV- group (489 (336-708) mins) (p = 0.029). Similarly, the operative time for recipients was longer in the MHV+ group (660 (428-831) mins) compared to MHV- (579 (359-1214) mins) (p = 0.023). MHV- grafts were heavier compared to MHV+ grafts (918 vs 711 g, p = 0.017). Recipient mortality rates and Kaplan-Meier survival analysis were comparable (p = 0.411). All donors were well at last review.

CONCLUSION

Both MHV+ and MHV- grafts are safe for the donor and recipient. The decision to take the MHV should be based on specific donor-recipient characteristics.

Impact of the Inferior Right Hepatic Veins on Right Liver Lobe Regeneration in Living-Donor Liver Transplant: 3-Dimensional Computed Tomography Scan Analyses in Donors and Recipients

OBJECTIVES

The presence of an inferior right hepatic vein significantly modifies the outflow pattern of the right liver and may have an impact on graft regeneration.

MATERIALS AND METHODS

Study patients were donors and recipients with 3-dimensional computed tomography scan simulation. We studied the physiologic impact of the inferior right hepatic veins on right liver regeneration in donors of left lobe grafts (step1; n = 60 patients) and the efficacy of a inferior right hepatic vein reconstruction policy based on a vessel caliber > 5 mm criteria in recipients of right liver grafts (step 2; n = 38 patients).

RESULTS

In step 1, the regeneration rate at 1 month was comparable between future liver remnants with inferior right hepatic vein (regeneration rate of 28.3%) and without inferior right hepatic vein (regeneration rate of 30.2%). In step 2, at 3 months after living-donor liver transplant, we observed no significant differences in regeneration rates among grafts anatomically without an inferior right hepatic vein (regeneration rate of 60.7%), grafts with an inferior right hepatic vein but no reconstruction (regeneration rate of 64.9%), and grafts with an inferior right hepatic vein and its reconstruction (regeneration rate of 68.1%). Within the latter subgroup, grafts with a dominant inferior right hepatic vein showed a greater regeneration of the anterior sector with inversion of the anterior-to-posterior sector regeneration ratio compared with right hepatic vein-dominant grafts (inferior right hepatic vein-dominant vs right hepatic vein-dominant showed anterior sector regeneration rates of 85.7% vs 52.1%; P = .02; anterior/posterior sector regeneration ratio was 2.3 vs 0.6, respectively; P = .04).

CONCLUSIONS

The reconstruction policy for inferior right hepatic vein with caliber > 5 mm is effective but should be implemented with computed tomography scan simulation. Right lobe grafts with a dominant inferior right hepatic vein are at higher risk of impaired regeneration due to expected large volumes of hepatic venous congestion if the middle hepatic veins tributaries or the inferior right hepatic veins are not reconstructed and an increased rate of right hepatic vein complications.

Variations in the vascular and biliary structures of the liver: a comprehensive anatomical study

PURPOSE

Vascular structures of the liver and the bile ducts are crucial during liver transplantation or liver resection surgery. Here, we report on variations in the vascular structures and bile ducts of 200 patients.

MATERIALS AND METHODS

We reviewed magnetic resonance cholangiopancreatographic and multiple-detector computed tomographic data.

RESULTS

Michels type 1 was detected in 54% of the patients. The other most common variations were, respectively, Michels type 5 (13%) and type 2 (11%). Unclassified variations were defined as Michels type 11; 5% of patients were in this group. Type 1 variations in the hepatic portal vein were detected in 76% of our study group. Other common variations were type 2 (9%) and type 3 (8.5%). The left and intermediate hepatic veins united to become a single vein and then joined the inferior vena cava in 64% of the patients. The right, intermediate, and left hepatic veins joined the inferior vena cava separately in 36% of the patients. Type A, which represents the classic anatomy of the bile duct, was observed in 51.5% of our patients. Type C1 and type B were detected in 15% and 12% of patients, respectively.

CONCLUSIONS

We describe vascular and biliary variations in the livers of our patients.

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.

Venous drainage map of the liver for complex hepatobiliary surgery and liver transplantation

BACKGROUND

Inflow and outflow patency of the liver parenchyma is required to maximize the metabolic function of the liver. However, the definition and distribution of hepatic venous drainage regions has yet to be reported. The aim of this study was to define major hepatic venous tributaries and investigate the mean drainage volume of each territory.

METHODS

Three-dimensional (3D) simulations from the livers of 100 healthy donors were reviewed for living donor liver transplantation to determine the distribution of the significant hepatic venous tributaries and the drainage patterns of each segment.

RESULTS

The left hepatic vein (LHV), middle hepatic vein (MHV), and right hepatic vein (RHV) contributed a mean drainage of 20.7%, 32.7%, and 39.6% of the entire liver, respectively. Accessory hepatic veins accounted for remaining 7.0%. The middle right hepatic vein (MRHV) and inferior right hepatic vein (IRHV) accounted for a mean total drainage of 8.0% and 10.6%, respectively, when they present. In addition, major tributaries of hepatic veins were clearly detected, and their typical distributions were described.

CONCLUSIONS

Knowledge of hepatic venous territories is necessary for complex hepatobiliary surgery. This "venous drainage map" may provide useful information for complex liver surgery and transplantation.

Standardized surgical techniques for adult living donor liver transplantation using a modified right lobe graft: a video presentation from bench to reperfusion

After having experienced more than 2,000 cases of adult living donor liver transplantation (LDLT), we established the concepts of right liver graft standardization. Right liver graft standardization intends to provide hemodynamics-based and regeneration-compliant reconstruction of vascular inflow and outflow. Right liver graft standardization consists of the following components: Right hepatic vein reconstruction includes a combination of caudal-side deep incision and patch venoplasty of the graft right hepatic vein to remove the acute angle between the graft right hepatic vein and the inferior vena cava; middle hepatic vein reconstruction includes interposition of a uniform-shaped conduit with large-sized homologous or prosthetic grafts; if the inferior right hepatic vein is present, its reconstruction includes funneling and unification venoplasty for multiple short hepatic veins; if donor portal vein anomaly is present, its reconstruction includes conjoined unification venoplasty for two or more portal vein orifices. This video clip that shows the surgical technique from bench to reperfusion was a case presentation of adult LDLT using a modified right liver graft from the patient's son. Our intention behind proposing the concept of right liver graft standardization is that it can be universally applicable and may guarantee nearly the same outcomes regardless of the surgeon's experience. We believe that this reconstruction model would be primarily applied to a majority of adult LDLT cases.

Split liver transplantation: What’s unique?

The intraoperative management of split liver transplantation (SLT) has some unique features as compared to routine whole liver transplantations. Only the liver has this special ability to regenerate that confers benefits in survival and quality of life for two instead of one by splitting livers. Primary graft dysfunction may result from small for size syndrome. Graft weight to recipient body weight ratio is significant for both trisegmental and hemiliver grafts. Intraoperative surgical techniques aim to reduce portal hyperperfusion and decrease venous portal pressure. Ischemic preconditioning can be instituted to protect against ischemic reperfusion injury which impacts graft regeneration. Advancement of the technique of SLT is essential as use of split cadaveric grafts expands the donor pool and potentially has an excellent future.

Risk of venous congestion in live donors of extended right liver graft

AIM: To investigate middle hepatic vein (MHV) management in adult living donor liver transplantation and safer remnant volumes (RV).

METHODS: There were 59 grafts with and 12 grafts without MHV (including 4 with MHV-5/8 reconstructions). All donors underwent our five-step protocol evaluation containing a preoperative protocol liver biopsy Congestive vs non-congestive RV, remnant-volume-body-weight ratios (RVBWR) and postoperative outcomes were evaluated in 71 right graft living donors. Dominant vs non-dominant MHV anatomy in total liver volume (d-MHV/TLV vs nd-MHV/TLV) was constellated with large/small congestion volumes (CV-index). Small for size (SFS) and non-SFS remnant considerations were based on standard cut-off- RVBWR and RV/TLV. Non-congestive RVBWR was based on non-congestive RV.

RESULTS: MHV and non-MHV remnants showed no significant differences in RV, RV/TLV, RVBWR, total bilirubin, or INR. SFS-remnants with RV/TLV < 30% and non-SFS-remnants with RV/TLV ≥ 30% showed no significant differences either. RV and RVBWR for non-MHV (n = 59) and MHV-containing (n = 12) remnants were 550 ± 95 mL and 0.79 ± 0.1 mL vs 568 ± 97 mL and 0.79 ± 0.13, respectively (P = 0.423 and P = 0.919. Mean left RV/TLV was 35.8% ± 3.9%. Non-MHV (n = 59) and MHV-containing (n = 12) remnants (34.1% ± 3% vs 36% ± 4% respectively, P = 0.148. Eight SFS-remnants with RVBWR < 0.65 had a significantly smaller RV/TLV than 63 non-SFS-remnants with RVBWR ≥ 0.65 [SFS: RV/TLV 32.4% (range: 28%-35.7%) vs non-SFS: RV/TLV 36.2% (range: 26.1%-45.5%), P < 0.009. Six SFS-remnants with RV/TLV < 30% had significantly smaller RVBWR than 65 non-SFS-remnants with RV/TLV ≥ 30% (0.65 (range: 0.6-0.7) vs 0.8 (range: 0.6-1.27), P < 0.01. Two (2.8%) donors developed reversible liver failure. RVBWR and RV/TLV were concordant in 25%-33% of SFS and in 92%-94% of non-SFS remnants. MHV management options including complete MHV vs MHV-4A selective retention were necessary in n = 12 vs n = 2 remnants based on particularly risky congestive and non-congestive volume constellations.

CONCLUSION: MHV procurement should consider individual remnant congestive- and non-congestive volume components and anatomy characteristics, RVBWR-RV/TLV constellation enables the identification of marginally small remnants.

Hepatic veins in presurgical planning of hepatic resection: what a radiologist should know

Hepatic resection is considered to be feasible when all malignant nodules can be technically excised. The goal of the surgical approach is to optimize the oncologic resection (negative margins), sparing the non-cancerous hepatic parenchyma. The outflowing hepatic vein (HV) of that particular liver remnant must be intact in order to preserve its function. The purpose of this article is to familiarize radiologists with anatomy and anatomical variants of HVs, with special emphasis on segmental venous drainage for presurgical planning of hepatic resections. We focus on information which radiologist should give to hepatic surgeon to choose proper surgical approach. Radiologist's familiarity with the anatomy and anatomical variants of HVs is essential for accurate surgical planning to avoid venous congestion as postoperative complication. Any clinically important hepatic vein variation detected on presurgical imaging should be carefully recorded in the radiology report.

Anomalous hepatic vein anatomy of left lateral section grafts and customized unification venoplasty for pediatric living donor liver transplantation

In liver transplantation, a left lateral section (LLS) graft may have an unusual variant left hepatic vein (LHV) anatomy. This study was designed to analyze the incidence of unusual LHV variants and to determine technical methods for effective reconstruction in infant recipients weighing approximately 10 kg or less. The study comprised 3 parts: an LHV variation analysis, a simulation-based design for the technical modification of graft LHV venoplasty, and its clinical application. The LHV anatomy of 300 potential LLS graft donors was classified into 4 types according to the number and location of the hepatic vein openings: (1) a single opening (n = 218 or 72.7%); (2) 2 large adjacent openings (n = 29 or 9.7%); (3) 2 adjacent openings, 1 large and 1 small (n = 34 or 11.3%); and (4) 2 widely spaced openings (n = 19 or 6.3%). Types 2 and 3 required wedged unification venoplasty, and type 4 required additional vein interposition. In a series of 49 cases using LLS grafts, the graft hepatic vein complication rate was 4.5% at 3 years; stenting was necessary for 1 of the 36 type 1 LHV grafts (2.8%) and for 1 of the 13 type 2-4 LHV grafts (7.7%, P = 0.46). A customized interposition-wedged unification venoplasty technique for coping with type 4 vein variations was developed with a simulation-based approach, and it was successfully applied to a 10-month-old male infant receiving an LLS graft with a type 4 LHV. In conclusion, nearly all LHV variations can be effectively managed with customized unification venoplasty. These venoplasty techniques represent beneficial surgical options as part of graft standardization for hepatic vein reconstruction in pediatric living donor liver transplantation.

Standardization of modified right lobe grafts to minimize vascular outflow complications for adult living donor liver transplantation

BACKGROUND

After >2000 adult living donor liver transplants (LDLTs), we observed minimization of the complication rate using case-by-case modification of venous outflow reconstruction in right liver graft (RLG), standardization seeking intend to provide a hemodynamic- based, regeneration-compliant hepatic outflow reconstruction.

METHODS

We retrospectively examined 100 consecutive adult LDLT using modified RLG before and after application of RLG standardization to compare the 6-month incidences of vascular outflow complications.

RESULT

The right hepatic vein stenting rate for first 6 months was 5% in the customized group and 1% in the standardized group (P=.212). The middle hepatic vein stenting rate for first 6 months was 9% in the customized group and 4% in the standardized group (P=.373). The inferior right hepatic vein stenting rate for first 6 months was 12.8% in the customized group and 7.1% in the standardized group (P=.472). The overall 6-month patient survival rate was 94% in the customized group and 95% in the standardized group (P=.867). The overall incidence of significant RLG venous outflow complications was 19% in the customized group and 8% in the standardized group (P=.023).

CONCLUSION

Standardization as a universal graft model seemed to be more effective and feasible than conventional graft customization requiring individualized case-by-case modification.

Reconstruction of inferior right hepatic veins in living donor liver transplantation using right liver grafts

Because revascularization of the inferior right hepatic vein (IRHV) is a major component of right liver graft (RLG) reconstruction, we assessed the surgical techniques and clinical outcomes of IRHV reconstruction so that we could formulate practical guidelines for standardized procedures. From July 2004 to February 2010, we performed separate IRHV reconstructions in 487 of 1142 adult RLG recipients (42.7%). These recipients included 364 patients with a natural single IRHV and 123 patients with multiple IRHVs; in the latter group, the IRHVs were unified by venoplasty, which enabled a single anastomosis. The 1-year stenosis rates for the single-vein and venoplasty groups were 23% and 18.9%, respectively, and the early stent insertion rates were 7.1% and 9.8%, respectively (P = 0.09). Late IRHV occlusion did not lead to graft dysfunction, and all large major IRHVs were patent. A morphometric analysis showed that IRHV stenosis was associated with IRHV stretching and an anastomotic level discrepancy. This led to refinements of the surgical techniques: IRHV orifices were shaped into funnels, and the IRHV anastomosis was accurately placed at the recipient inferior vena cava (IVC). In an ongoing prospective study of 35 patients, our funneling unification venoplasty resulted in only 1 episode (2.9%) of early IRHV stenosis requiring stenting at a median follow-up of 8 months. The final configurations of the reconstructed IRHVs after funneling unification venoplasty and extensive IVC dissection were very similar to those of the native donor liver. In conclusion, we suggest that in combination with extensive recipient IVC dissection, funneling and unification venoplasty techniques are useful for securely reconstructing single or multiple IRHVs during the implantation of RLGs.

Long-term follow-up after right hepatectomy for adult living donation and attitudes toward the procedure

OBJECTIVES

To determine the long-term health status of donors after right hepatectomy for adult live donor liver transplantation (ALDLT).

BACKGROUND

The long-term outcomes for ALDLT donors are unknown.

METHODS

ALDLT donors undergoing right hepatectomy from April 1998 to June 2007 were invited to complete a questionnaire regarding health status, satisfaction (1-10/worst-best scale), self-esteem, willingness to donate again, and suggestions for improvement. In addition, donor files and cholecystectomy specimens were reviewed. Fisher's exact test, Kaplan-Meier and logistic regression analyses were performed.

RESULTS

Eighty-three donors were contacted (median age: 36 years; median follow-up: 69 months). 39 (47%) were free of symptoms. The remaining 44 (53%) reported: intolerance to fatty meals and diarrhea (31%), gastroesophageal reflux associated with left liver hypertrophy (9%), incisional discomfort requiring pain medications (6%), severe depression requiring hospitalization (4%), rib pain affecting lifestyle (2%), and exacerbation of psoriasis (1%). Median satisfaction score was 8. Self-esteem diminished in 5%. Thirty-nine (47%) recommended improvements particularly more detailed informed donor consent and a centralized living donor liver registry. Seventy-eight (94%) were willing to donate again. There were no differences between donors with and without complaints with respect to: donor age, gender, early complications and follow-up time, young-to-old donation, recipient diagnosis of malignancy and death of the recipient. Noninflamed donor cholecystectomy specimens correlated with intolerance to fatty meals and diarrhea (P = 0.001).

CONCLUSIONS

ALDLT donors are at risk for long-term complaints that are neither reflected nor related to early complications. This information should be included in both the donor evaluation and the ALDLT decision-making process.

Consensus report of the 4th International Forum for Gadolinium-Ethoxybenzyl-Diethylenetriamine Pentaacetic Acid Magnetic Resonance Imaging

This paper reports on issues relating to the optimal use of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid magnetic resonance imaging (Gd-EOB-DTPA MR imaging) together with the generation of consensus statements from a working group meeting, which was held in Seoul, Korea (2010). Gd-EOB-DTPA has been shown to improve the detection and characterization of liver lesions, and the information provided by the hepatobiliary phase is proving particularly useful in differential diagnoses and in the characterization of small lesions (around 1-1.5 cm). Discussion also focused on advances in the role of organic anion-transporting polypeptide 8 (OATP8) transporters. Gd-EOB-DTPA is also emerging as a promising tool for functional analysis, enabling the calculation of post-surgical liver function in the remaining segments. Updates to current algorithms were also discussed.

Small for size syndrome following living donor and split liver transplantation

The field of liver transplantation is limited by the availability of donor organs. The use of living donor and split cadaveric grafts is one potential method of expanding the donor pool. However, primary graft dysfunction can result from the use of partial livers despite the absence of other causes such as vascular obstruction or sepsis. This increasingly recognised phenomenon is termed “Small-for-size syndrome” (SFSS). Studies in animal models and humans have suggested portal hyperperfusion of the graft combined with poor venous outflow and reduced arterial flow might cause sinusoidal congestion and endothelial dysfunction. Graft related factors such as graft to recipient body weight ratio < 0.8, impaired venous outflow, steatosis > 30% and prolonged warm/cold ischemia time are positively predictive of SFSS. Donor related factors include deranged liver function tests and prolonged intensive care unit stay greater than five days. Child-Pugh grade C recipients are at relatively greater risk of developing SFSS. Surgical approaches to prevent SFSS fall into two categories: those targeting portal hyperperfusion by reducing inflow to the graft, including splenic artery modulation and portacaval shunts; and those aiming to relieve parenchymal congestion. This review aims to examine the controversial diagnosis of SFSS, including current strategies to predict and prevent its occurrence. We will also consider whether such interventions could jeopardize the graft by compromising regeneration.