Comparison of CT methods for determining graft steatosis in living donor liver transplantation

Effect of Portal Vein Types on Estimated Remnant Volume in Living Donor: Preoperative CT Assessment

PURPOSE

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.

MATERIALS AND METHODS

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.

RESULTS

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).

CONCLUSION

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.

Non-invasive testing and risk-stratification in patients with MASLD

The development and validation of non-invasive fibrosis tests (NITs) has changed clinical practice in Hepatology over the last 15 years. Metabolic associated steatotic liver disease (MASLD), formerly known as non-alcoholic fatty liver disease (NAFLD), is the most prevalent liver disease in western countries, with up to a third of the unselected adult population affected. In this article, we review the use of NITs in the diagnosis and staging of MASLD. We discuss their use in the diagnosis of steatosis, steatohepatitis and fibrosis and critically evaluate recently published data. These NITs include a variety of approaches, such as serum markers like FIB-4, pro-C3 and ELF, imaging techniques like Fibroscan® and MRE, and combined scores like Agile 3+ and Agile 4, offering a range of options for healthcare providers. Furthermore, these non-invasive tests also serve as valuable prognostic tools, allowing for better risk assessment and improved patient management, particularly in predicting liver-related events and overall mortality.

Identification of hepatic steatosis in living liver donors by machine learning models

Selecting an optimal donor for living donor liver transplantation is crucial for the safety of both the donor and recipient, and hepatic steatosis is an important consideration. We aimed to build a prediction model with noninvasive variables to evaluate macrovesicular steatosis in potential donors by using various prediction models. The study population comprised potential living donors who had undergone donation workup, including percutaneous liver biopsy, in the Republic of Korea between 2016 and 2019. Meaningful macrovesicular hepatic steatosis was defined as >5%. Whole data were divided into training (70.5%) and test (29.5%) data sets based on the date of liver biopsy. Random forest, support vector machine, regularized discriminant analysis, mixture discriminant analysis, flexible discriminant analysis, and deep neural network machine learning methods as well as traditional logistic regression were employed. The mean patient age was 31.4 years, and 66.3% of the patients were men. Of the 1652 patients, 518 (31.4%) had >5% macrovesicular steatosis on the liver biopsy specimen. The logistic model had the best prediction power and prediction performances with an accuracy of 80.0% and 80.9% in the training and test data sets, respectively. A cut-off value of 31.1% for the predicted risk of hepatic steatosis was selected with a sensitivity of 77.7% and specificity of 81.0%. We have provided our model on the website (https://hanseungbong.shinyapps.io/shiny_app_up/) under the name DONATION Model. Our algorithm to predict macrovesicular steatosis using routine parameters is beneficial for identifying optimal potential living donors by avoiding superfluous liver biopsy results.

Peri-transplant management of nonalcoholic fatty liver disease in liver transplant candidates

The incidence of non-alcoholic fatty liver disease (NAFLD) is rapidly growing, affecting 25% of the world population. Non-alcoholic steatohepatitis (NASH) is the most severe form of NAFLD and affects 1.5% to 6.5% of the world population. Its rising incidence will make end-stage liver disease (ESLD) due to NASH the number one indication for liver transplantation (LT) in the next 10 to 20 years, overtaking Hepatitis C. Patients with NASH also have a high prevalence of associated comorbidities such as type 2 diabetes, obesity, metabolic syndrome, cardiovascular disease, and chronic kidney disease (CKD), which must be adequately managed during the peritransplant period for optimal post-transplant outcomes. The focus of this review article is to provide a comprehensive overview of the unique challenges these patients present in the peritransplant period, which comprises the pre-transplant, intraoperative, and immediate postoperative periods.