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Segmental hepatic anatomy. (a) Illustration shows the segmental anatomy of the liver along the vertical plane, which divides the right and left lobes and passes through the middle hepatic vein. (b) Volumerendered CT image shows the volumetric measurements of the right and left lobes of the liver. Right hemihepatectomy is performed in patients whose left lobe accounts for at least 30% of the liver volume. (c) Axial CT image of the liver shows the plane that divides the right and left lobes and passes through the middle hepatic vein. (d) Illustration shows vascular (arrowheads) and biliary (arrow) anastamoses in a living donor transplantation of the right lobe of the liver.
Source publication
Therapeutic strategies for treating patients with liver failure, particularly optimization of liver transplantation, are constantly being refined, with the goal of improving long-term survival with the lowest risk for toxicity in donors and recipients. Optimal planning for liver transplantation requires a multidisciplinary collaboration between the...
Contexts in source publication
Context 1
... hemihepatectomy (segments V-VIII) is performed if the volume of the donor's left lobe is more than 30% of the total hepatic volume. Inclusion of the middle hepatic vein in the graft is controversial; however, it may be included to avoid congestion of the right paramedian seg- ment in the recipient (Figs 1, 2) (10-15). ...
Context 2
... availability of dedicated software programs allows radiologists to delineate the liver and resec- tion margins, after which integrated software may be used to calculate the volume of the entire liver, the potential residual volume in the donor, and the potential volume in the recipient (Fig 10). The ability to measure donor and recipient liver vol- umes enables optimal utilization of the liver tissue to prevent small-for-size syndrome. ...
Citations
... In the United States, it is standard for the estimated liver remnant volume (ERLV) to be a minimum of 30% of the overall liver volume in the case of healthy donors. However, for elderly patients, a more cautious estimate of over 35% may be considered [5][6][7][8]. ...
The aim of this study is to examine the effect of portal vein types on the ratio of the right-left lobe liver volumes, as well as the insufficient estimated remnant liver volume (ERLV) during the preoperative assessment of donor candidates for right-lobe liver transplantation.
The preoperative abdominal CT examinations of the donor candidates in a single institution between December 2018 and May 2022 were retrospectively evaluated. Portal vein types are divided into 3; classical anatomy was considered type 1, PV trifuction was considered type 2, and if the first branch arising from the main portal vein is the right posterior branch, it was accepted as type 3. Other configurations were defined as type 4. The total, right-left lobe liver volumes, the ERLV, and the portal vein variations were noted. The chi-square test was performed to assess the correlation between portal vein types, the ratio of the right-left lobe volumes, and the ERLV ratio below 30%. Tamhane’s T2 post hoc tests were performed for pairwise comparison to assess the right-left lobe volume ratio among groups.
287 donor candidates (mean age, 35 years ± 8.2; 174 men) were evaluated. The volume ratio of median volume of the right and left lobe was significantly higher in candidates with type 3 portal veins compared to those with type 1 portal veins (2 (1.3–3.5) and 2.1 (1.6–3.2), respectively, p = 0.017). The ERLV ratio below 30% was significantly higher in donor candidates with type 3 portal veins (42.9%) compared to those with type 1 and 2 portal veins (24.6%, 20%)) respectively, p = 0.030).
Due to its propensity to result in insufficient ERLV in the donor, the presence of a type 3 portal vein should be evaluated during the preoperative evaluation.
Secondary abstract: This study suggests that donor candidates with type 3 portal vein exhibit a notable rise in the frequency of insufficient remnant liver volume during the preoperative assessment.
... Advances in organ procurement, surgical techniques, and immunosuppression have led to excellent short-and long-term results with a 5-year patient survival rate exceeding 85% [1][2][3]. Imaging methods are key elements for transplantation programs as they have been shown to assist surgical planning, to guide intraoperative surgical technique, and can be effectively applied to detect post-operative complications [4][5][6][7][8][9][10]. ...
Liver transplantation is the state-of-the-art curative treatment for end-stage liver disease. Imaging is a key element in the detection of postoperative complications. So far, limited data is available regarding the best radiologic approach to monitor children after liver transplantation.
To harmonize the imaging of pediatric liver transplantation, the European Society of Pediatric Radiology Abdominal Taskforce initiated a survey addressing the current status of imaging including the pre-, intra-, and postoperative phases. This paper reports the responses related to postoperative imaging.
An online survey, initiated in 2021, asked European centers performing pediatric liver transplantation 48 questions about their imaging approach. In total, 26 centers were contacted, and 22 institutions from 11 countries returned the survey.
All sites commence ultrasound (US) monitoring within 24 h after liver transplantation. Monitoring frequency varies across sites, ranging from every 8 h to 72 h in early, and from daily to sporadic use in late postoperative phases. Predefined US protocols are used by 73% of sites. This commonly includes gray scale, color Doppler, and quantitative flow assessment. Alternative flow imaging techniques, contrast-enhanced US, and elastography are applied at 31.8%, 18.2%, and 63.6% of sites, respectively. Computed tomography is performed at 86.4% of sites when clarification is needed. Magnetic resonance imaging is used for selected cases at 36.4% of sites, mainly for assessment of biliary abnormalities or when blood tests are abnormal.
Diagnostic imaging is extensively used for postoperative surveillance of children after liver transplantation. While US is generally prioritized, substantial differences were noted in US protocol, timing, and monitoring frequency. The study highlights potential areas for future optimization and standardization of imaging, essential for conducting multicenter studies.
... planning, to guide intraoperative surgical technique, and can be effectively applied to detect postoperative complications [4][5][6][7][8][9]. Preoperatively, the main objective for dedicated abdominal imaging is to measure organ and vessel sizes and depict vascular anatomy and patency, as well as to rule out contraindications potentially complicating surgery [4,6,[10][11][12]. ...
Background
Liver transplantation is the state-of-the-art curative treatment in end-stage liver disease. Imaging is a key element for successful organ-transplantation to assist surgical planning. So far, only limited data regarding the best radiological approach to prepare children for liver transplantation is available.
Objectives
In an attempt to harmonize imaging surrounding pediatric liver transplantation, the European Society of Pediatric Radiology (ESPR) Abdominal Taskforce initiated a survey addressing the current status of imaging including the pre-, intra-, and postoperative phase. This paper reports the responses on preoperative imaging.
Material and methods
An online survey, initiated in 2021, asked European centers performing pediatric liver transplantation 44 questions about their imaging approach. In total, 26 centers were contacted and 22 institutions from 11 countries returned the survey. From 2018 to 2020, the participating centers collectively conducted 1,524 transplantations, with a median of 20 transplantations per center per annum (range, 8–60).
Results
Most sites (64%) consider ultrasound their preferred modality to define anatomy and to plan surgery in children before liver transplantation, and additional cross-sectional imaging is only used to answer specific questions (computed tomography [CT], 90.9%; magnetic resonance imaging [MRI], 54.5%). One-third of centers (31.8%) rely primarily on CT for pre-transplant evaluation. Imaging protocols differed substantially regarding applied CT scan ranges, number of contrast phases (range 1–4 phases), and applied MRI techniques.
Conclusion
Diagnostic imaging is generally used in the work-up of children before liver transplantation. Substantial differences were noted regarding choice of modalities and protocols. We have identified starting points for future optimization and harmonization of the imaging approach to multicenter studies.
... There are only 55.61% of people who have the usual anatomy of the hepatic arterial. The left gastric artery can be used to substitute the left hepatic artery, and the superior mesenteric artery can be used to replace the right hepatic artery, in addition to auxiliary hepatic arteries on the right or left (6) . ...
... Those patients requiring liver transplants have a poor scan window in ultrasonography and ultimately need contrast-enhanced CT, multidetector CT (MDCT) scan or MRI scan with or without 3D reconstruction. 13,[18][19][20][21] Certainly, these scan methods are much more sensitive and specific in detecting the variations of anatomy of hepatic and portal venous system. We used ultrasonography in our study as it is the most affordable, cheap, non-invasive, and safe initial investigative procedure for a poor set-up in a peripheral medical college. ...
Introduction: Knowledge about venous patterns (especially portal and hepatic venous) and their variations are extremely crucial for liver transplantation and other surgical procedures on liver. Studies have been done at national or international level on variations of hepatic venous patterns by CT or MRI or by dissection on cadaveric liver. No definitive or authentic study on this topic could be noted in electronic and print media, as well as in standard textbook. Considering low cost and noninvasive nature, we utilized ultrasonography to bridge this lacuna.
Aim: To estimate prevalence and types of anatomical variations of hepatic venous system and to determine association of among variations.
Materials and methods: It is an observational cross-sectional study where ultrasonographic evaluation of hepatic venous pattern on adult population of either sex (consecutive sampling) without any major liver disorders was done in RG Kar Medical College and data were analyzed with appropriate statistical procedures.
Results: Normal hepatic venous pattern along with normal portal venous pattern is much higher in our study, which is a unique finding. The proportion of normal portal venous pattern is more in extra hepatic bifurcation group. Variations of portal vein and normal hepatic venous pattern are more in case of intrahepatic bifurcation of portal venous branching group. Overall presence of intrahepatic bifurcation of portal vein is significantly higher than extrahepatic bifurcation.
Conclusions: This study provides an updated database for the prevalence and distribution of anatomic variations of the hepatic venous and portal venous system.
... An accurate assessment for tumor extent with an appropriate imaging modality is of high importance in LT planning. CT is the imaging modality with a good sensitivity and specificity not only for the assessment of the vessels, tumor extent, and extrahepatic metastases in planning an LT but also for the assessment of possible anatomical vessel variants to reduce the possible complications in LT and eventually of outcome [41,42]. Contrast-enhanced MRCP with gadolinium ethoxy benzylic diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) is well suited for assessing the biliary system [43], both before and after LT. ...
... HEHE is a rare tumor entity; however, the indication for LT even in advanced stage is given [49]. The current imaging criteria before and after transplantation should be considered [41,44]. ...
... Imaging findings should include number, anatomical location and radiological tumor pattern, extrahepatic metastases, and vascular and biliary complications [55] since all of these factors have been reported to correlate with outcome [56]. In general, great attention should be paid to accurate pre-and especially posttransplant imaging to detect complications after LT, as these also have an impact on the outcome [41,44]. ...
Introduction:
Liver transplantation (LT) is today's standard treatment for both end-stage liver disease and tumors; however, suitable grafts for LT are a scarce resource and outcome after LT is highly dependent on its underlying indication. Thus, patients must be carefully selected to optimize the number of life years gained per graft. This comprehensive and systematic review critically reflects the most recently published oncological outcome data after LT in malignancies based on the preoperative radiological findings.
Methods:
A systematic literature search was conducted to detect preferentially most recent high-volume series or large database analysis on oncological outcomes after LT for both primary liver cancer and liver metastases between January 1, 2019, and November 14, 2020. A comprehensive review on the radiological assessment of the reviewed liver malignancies is included and its preoperative value for an outcome-driven indication reflected.
Results:
Twenty most recent high-volume or relevant studies including a total number of 2,521 patients were identified including 4, 4, 4, 4, 3, and 1 publications on oncological outcome after LT for hepatocellular carcinoma, cholangiocellular carcinoma, hepatic epitheloid hemangioendothelioma, hepatoblastoma, and both metastatic neuroendocrine tumors and colorectal cancer, respectively. The overall survival is comparable to patients without tumors if patients with malignancies are well selected for LT; however, this is highly dependent on tumor entity, tumor stage, and both neoadjuvant and concomitant treatment.
Discussion/conclusion:
LT is a promising option for better survival in patients with malignant liver tumors in selected patients; however, the indication must be critically discussed prior to LT in every single case in the context of organ shortage.
... Digital subtraction angiography [DSA], an invasive procedure, is regarded as the gold standard in the evaluation of vascular structures. DSA has limitations in demonstrating a hepatic venous system [15]. Some variations can be missed in DSA like in selective angiographic processes because of the position of the tip of the catheter, or when a high-quality angiography cannot be obtained [19]. ...
... All surgical and clinical relevant information regarding recipients and donors can be obtained with a single breath-hold MDCT angiography. MDCT [6,15,19]. ...
PurposePreoperative evaluation of the hepatic vasculature is necessary to minimize mortality and morbidity during various surgeries due to the complexity of liver anatomy. The purpose of our investigation is to determine the anatomical variations in the hepatic vascular system by using multidetector computed tomography.Methods
In this observational study, 500 patients aged between 1 and 86 years were randomly chosen from a patient population referred for computed tomography angiography for various clinical indications. Multidetector computed tomography angiography examinations were performed using a 128 detector scanner. The area from the lower thoracic spine to symphysis pubis level, with the patient in a supine position, was adopted as the field of view. The percentage of occurrence of each of the vascular variant was determined.ResultsNormal arterial anatomy [Type I] was seen in 306 patients [61.2%]. Replaced left hepatic artery from the left gastric artery was the most common variant in our study, which was seen in 57 patients [11.4%]. Classic hepatic venous anatomy was found in 261 [52.2%] patients. An accessory inferior right hepatic vein was found in 110 [22%] patients. A large early branch of segment VIII into middle hepatic vein was found in 157 patients [31.4%]. Extraparenchymal branching of the right anterior portal vein from the left portal vein was the most common anomaly found in 12 [2.4%] patients.Conclusions
Computed tomography angiography can be used in preoperative evaluation in various hepatobiliary surgeries and interventional procedures, which give a lot of information regarding parenchyma and vascular system.
... Preoperative, contrast-enhanced computed tomography (CT) is important for the planning of LDLT. Preoperative CT of the donor is used to determine the suitability for LDLT and to establish a surgical plan by identifying the hepatic anatomy and the presence of liver disease and by assessing the liver volumetry [8]. However, CT images contain data beyond the gross anatomy which are difficult to quantify with the human eye. ...
PurposeThe aim of the study is to predict the rate of liver regeneration in recipients after living-donor liver transplantation using preoperative CT texture and shape analysis of the future graft.Methods102 donor–recipient pairs who underwent living-donor liver transplantation using right lobe grafts were retrospectively included. We semi-automatically segmented the future graft from preoperative CT. The volume of the future graft (LVpre) was measured, and texture and shape analyses were performed. The graft liver was segmented from postoperative follow-up CT and the volume of the graft (LVpost) was measured. The regeneration index was defined by the following equation: [(LVpost−LVpre)/LVpre] × 100(%). We performed a stepwise, multivariate linear regression analysis to investigate the association between clinical, texture and shape parameters and the RI and to make the best-fit predictive model.ResultsThe mean regeneration index was 47.5 ± 38.6%. In univariate analysis, the volume of the future graft, energy, effective diameter, surface area, sphericity, roundnessm, compactness1, and grey-level co-occurrence matrix contrast as well as several clinical parameters were significantly associated with the regeneration index (p < 0.05). The best-fit predictive model for the regeneration index made by multivariate analysis was as follows: Regeneration index (%) = 127.020–0.367 × effective diameter − 1.827 × roundnessm + 47.371 × recipient body surface area (m2) + 12.041 × log(recipient white blood cell count) (× 103/μL)+ 18.034 (if the donor was female).Conclusion
The effective diameter and roundnessm of the future graft were associated with liver regeneration. Preoperative CT texture analysis of future grafts can be useful for predicting liver regeneration in recipients after living-donor liver transplantation.
... The segments involved in the right and left grafts of the donor's liver vary depending on the type of split used. The right liver graft typically includes the common bile duct and inferior vena cava (IVC), while the left liver graft has the main arterial trunk and middle hepatic vein [7]. ...
... As the right hepatic vein is the dominant vein in most patients, the inclusion of MHV in the graft will not cause any clinically significant congestion of liver in the donor. At the same time, the inclusion of the middle hepatic vein in the graft may also reduce congestion of the right para-median segment in the recipient [7]. A right hepatectomy graft is often collected without MHV and is at a higher risk for congestion of right para-median sector with increased risk of dysfunction and complications. ...
Infectious diseases of the liver are major causal factors leading to acute or chronic liver failure and end-stage liver failure necessitating Liver transplantation (LT). Parasitic infections (Alveolar echinococcosis) and viral hepatitis (HBV and HCV) in particular are prominent infectious diseases in China which carry substantial morbidity rate. Chronic infections of HBV and HCV have a high potential to develop Hepatocellular cancer (HCC). At the end stage or acute liver failure due to these infectious diseases, LT places itself as an effective treatment option. It is a complex procedure requiring the collaborative planning of a radiologist, transplant surgeon, oncologist, and hepatologist. The criteria required for liver transplantation are constantly being optimized with an aim of decreasing the risks involved and increasing the post-transplant survival rate. Role of imaging is crucial in differentiating the normal from abnormal anatomy of the liver, anatomical variants of the vasculature and biliary tree. It helps the transplant surgeon in deciding the technique which benefits both the donor and recipient, putting the graft to optimal use. In this article, we review the literature on infectious diseases (viral and parasitic) of the liver, their impact on the necessity to undergo hepatic transplantation while highlighting the role of imaging evaluation during pre-transplantation stage.
... Imaging plays an important role in the pretransplant evaluation for both the donor and the recipient. Understanding the arterial and venous anatomy of the recipient and the donor affects surgical technique and reduces potential intraoperative complications (100). Also, pretransplant volumetric assessment of the donor liver is important to ensure that at least 30%-35% of the pretransplant liver volume remains after surgery to prevent smallfor-size syndrome (101). ...
Primary sclerosing cholangitis (PSC) is a chronic progressive inflammatory disease of the bile ducts that leads to multifocal bile duct fibrosis, strictures, cholestasis, liver parenchymal changes, and ultimately cirrhosis. It more commonly occurs in young adults, with a variety of clinical and imaging manifestations. The cause of the disease is not known, but it has a strong association with inflammatory bowel disease and can overlap with other autoimmune diseases, including autoimmune hepatitis and immunoglobulin G4-related disease. Patients are predisposed to various hepatic and extrahepatic deteriorating complications, such as bile duct and gallbladder calculi, acute bacterial cholangitis, liver abscess, and portal hypertension, as well as malignancies including cholangiocarcinoma (CCA), gallbladder cancer, and colorectal carcinoma. Imaging has an essential role in diagnosis, surveillance, and detection of complications. MR cholangiopancreatography and endoscopic retrograde cholangiopancreatography have high specificity and sensitivity for detection of primary disease and assessment of disease progression. However, many patients with PSC are still diagnosed incidentally at US or CT. Novel imaging techniques such as transient elastography and MR elastography are used to survey the grade of liver fibrosis. Annual cancer surveillance is necessary in all PSC patients to screen for CCA and gallbladder cancer. Familiarity with PSC pathogenesis and imaging features across various classic imaging modalities and novel imaging techniques can aid in correct imaging diagnosis and guide appropriate management. The imaging features of the biliary system and liver parenchyma in PSC across various imaging modalities are reviewed. Imaging characteristics of the differential diagnosis of PSC, clinical associations, and complications are described. Finally, the role of imaging in evaluation of PSC progression, pre-liver transplant assessment, and post-liver transplant disease recurrence are discussed.©RSNA, 2019.
