Gd-EOB-DTPA-enhanced MRI for monitoring future liver remnant function after portal vein embolization and extended hemihepatectomy: A prospective trial

Harmonization of quantitative liver function evaluation using gadoxetate disodium-enhanced magnetic resonance imaging

OBJECTIVES

This study aimed to develop a clinically applicable harmonization method for the hepatocellular uptake index (HUI), a quantitative liver function index, using gadoxetate disodium-enhanced (EOB)-MRI, to ensure consistency across diverse MR systems.

MATERIALS AND METHODS

This retrospective study, approved by our institutional review board, included consecutive patients who underwent three-dimensional gradient-echo T1-weighted EOB-MRI, HUI measurements, indocyanine green disappearance rate (ICG-PDR), and albumin-bilirubin linear predictor (ALBI-LP) between April 2011 and June 2024. Six different MR systems were used for HUI measurements. A harmonization method using ALBI-LP was developed and validated for estimating liver reserves corresponding to ICG-PDR through statistical analysis of residuals.

RESULTS

A total of 498 patients (mean age, 68.0 years ± 11.6; 320 men) were evaluated. A statistically significant linear correlation was observed between HUI, ICG-PDR, and ALBI-LP in each MR system, leading to the determination of conversion factors for HUI harmonization. The harmonizing equation, harmonized HUI (h-HUI) = HUI･(Slope2'/-1.425)･0.955, was derived, with Slope2' representing the regression slope between HUI and ALBI-LP for each MR system. The standard deviation of the estimation error for ICG-PDR was significantly smaller using h-HUI by ALBI-LP (0.051, [0.048-0.054]) compared to non-harmonized HUI (0.060, [0.056-0.063]) or ALBI-LP (0.060, [0.057-0.064]), and equivalent to h-HUI by ICG-PDR (0.051, [0.045, 0.055]).

CONCLUSION

The HUI harmonized by the ALBI-LP is a clinically applicable method for ensuring the comparability of MR devices in quantitative liver reserve prediction using gadoxetate disodium-enhanced MR imaging.

KEY POINTS

Question The accurate prediction of quantitative liver function by hepatocyte-specific contrast-enhanced MRI necessitates the harmonization of MR systems. However, no established method has yet been identified. Findings In quantitative hepatic function assessment, albumin-bilirubin linear predictor can be employed to achieve harmonization between MR systems equivalent to the indocyanine green clearance test. Clinical relevance Quantitative liver function, as measured by the indocyanine green clearance test, can be accurately estimated using the hepatocellular uptake index, harmonized with the albumin-bilirubin linear predictor, across diverse MR systems.

Impact of aging on hepatic reserve after preoperative portal vein embolization in hepatectomy for perihilar cholangiocarcinoma

PURPOSE

In the current situation of an increasing older adult population with perihilar cholangiocarcinoma (PHCC), the benefits and risks of surgical treatment of PHCC in older people remain controversial. Portal vein embolization (PVE) is a useful preoperative procedure to improve hepatic reserve in the future remnant liver (FRL) and avoid postoperative liver failure after extended hepatectomy for PHCC. This study aimed to evaluate the influence of aging on PVE.

METHODS

We enrolled 25 patients who underwent right hepatectomy with percutaneous transhepatic PVE. Participants aged <70 years (n = 13) and ≥70 years (n = 12) were compared; correlation coefficients were evaluated using all cases. The FRL volume/total liver volume (FRLV/TLV) ratio and the indocyanine green (ICG) clearance rate (ICG-K) fraction of FRL to total liver (ICG-Krem) were analyzed as FRL hepatic reserves.

RESULTS

FRLV/TLV ratio increased after PVE in <70 years and ≥70 years groups (p = 0.002 and p = 0.013, respectively). The change in ICG-K values from before to after PVE varied between both groups (p = 0.040). The ICG-Krem value after PVE increased only in the <70 years group (p = 0.009). A review of all cases showed a negative correlation between the change (after - before PVE) in the ICG-K and ICG-Krem values and age (r = -0.4827, p = 0.0145 and r = -0.4328, p = 0.0306, respectively).

CONCLUSIONS

This study showed aging suppresses hepatic reserve improvement in the FRL, particularly in ICG clearance after PVE in PHCC cases.

CIRSE Standards of Practice on Portal Vein Embolization and Double Vein Embolization/Liver Venous Deprivation

This CIRSE Standards of Practice document is aimed at interventional radiologists and provides best practices for performing liver regeneration therapies prior to major hepatectomies, including portal vein embolization, double vein embolization and liver venous deprivation. It has been developed by an expert writing group under the guidance of the CIRSE Standards of Practice Committee. It encompasses all clinical and technical details required to perform liver regeneration therapies, revising the indications, contra-indications, outcome measures assessed, technique and expected outcomes.

Impact of Clinically Relevant Posthepatectomy Liver Failure Predicted by Preoperative Evaluation of Functional Remnant Hepatic Reserve

Background

Few studies have investigated the remnant hepatic functional reserve before hepatectomy by calculating the functional remnant liver rate (RLR) using three-dimensional computed tomography (3D-CT)/technetium-99m-diethylenetriamine-pentaacetic acid galactosyl human serum albumin (99mTc-GSA) single-photon emission CT (SPECT) fusion imaging. We aimed to preoperatively evaluate the predictive value of functional remnant liver rate (RLR) and indocyanine green (ICG) disappearance rate (KICG) in determining the occurrence of posthepatectomy liver failure (PHLF).

Summary of Background Data

The conventional method of volumetric rem-KICG calculated from remnant liver volume and the KICG is difficult to accurately reflect heterogenous remnant liver function.

Methods

In total, 106 patients who underwent major hepatectomy were retrospectively analysed. Of these, 24 (22.6%) developed clinically relevant PHLF grades B/C. We examined the ICG retention rate at 15 min (ICGR15) and KICG and constructed a 3D-CT/99mTc-GSA SPECT fusion image to calculate the volumetric RLR, functional RLR, volumetric rem-KICG, and functional rem-KICG.

Results

The multivariate analysis showed functional rem-KICG as the strongest independent risk factor for PHLF grade B/C. The functional-to-volumetric RLR ratios in the patients with portal vein obstruction and/or tumor volume of ≥500 mL was significantly higher. The volumetric rem-KICG determined that hepatectomy was unsafe in 7 patients, whereas the functional rem-KICG determined that it was unsafe in 3 patients.

Conclusions

Functional rem-KICG was more reliable than volumetric rem-KICG in predicting clinically relevant PHLF grade B/C, as the resected side’s hepatic status highly influenced the function of the remnant liver. This finding could lead to a wider application of this technique.

Volume-Assisted Estimation of Remnant Liver Function Based on Gd-EOB-DTPA Enhanced MR Relaxometry: A Prospective Observational Trial

In the context of liver surgery, predicting postoperative liver dysfunction is essential. This study explored the potential of preoperative liver function assessment by MRI for predicting postoperative liver dysfunction and compared these results with the established indocyanine green (ICG) clearance test. This prospective study included patients undergoing liver resection with preoperative MRI planning. Liver function was quantified using T1 relaxometry and correlated with established liver function scores. The analysis revealed an improved model for predicting postoperative liver dysfunction, exhibiting an accuracy (ACC) of 0.79, surpassing the 0.70 of the preoperative ICG test, alongside a higher area under the curve (0.75). Notably, the proposed model also successfully predicted all cases of liver failure and showed potential in predicting liver synthesis dysfunction (ACC 0.78). This model showed promise in patient survival rates with a Hazard ratio of 0.87, underscoring its potential as a valuable tool for preoperative evaluation. The findings imply that MRI-based assessment of liver function can provide significant benefits in the early identification and management of patients at risk for postoperative liver dysfunction.

CT-derived extracellular volume and liver volumetry can predict posthepatectomy liver failure in hepatocellular carcinoma

OBJECTIVES

Posthepatectomy liver failure (PHLF) is a severe complication of liver resection. We aimed to develop and validate a model based on extracellular volume (ECV) and liver volumetry derived from computed tomography (CT) for preoperative predicting PHLF in resectable hepatocellular carcinoma (HCC) patients.

METHODS

A total of 393 resectable HCC patients from two hospitals were enrolled and underwent multiphasic contrast-enhanced CT before surgery. A total of 281 patients from our hospital were randomly divided into a training cohort (n = 181) and an internal validation cohort (n = 100), and 112 patients from another hospital formed the external validation cohort. CT-derived ECV was measured on nonenhanced and equilibrium phase images, and liver volumetry was measured on portal phase images. The model is composed of independent predictors of PHLF. The under the receiver operator characteristic curve (AUC) and calibration curve were used to reflect the predictive performance and calibration of the model. Comparison of AUCs used the DeLong test.

RESULTS

CT-derived ECV, measured future liver remnant (mFLR) ratio, and serum albumin were independent predictors for PHLF in resectable HCC patients. The AUC of the model was significantly higher than that of the ALBI score in the training cohort, internal validation cohort, and external validation cohort (all p < 0.001). The calibration curve of the model showed good consistency in the training cohort and the internal and external validation cohorts.

CONCLUSIONS

The novel model contributes to the preoperative prediction of PHLF in resectable HCC patients.

CRITICAL RELEVANCE STATEMENT

The novel model combined CT-derived extracellular volume, measured future liver remnant ratio, and serum albumin outperforms the albumin-bilirubin score for predicting posthepatectomy liver failure in patients with resectable hepatocellular carcinoma.

KEY POINTS

• CT-derived ECV correlated well with the fibrosis stage of the background liver. • CT-derived ECV and mFLR ratio were independent predictors for PHLF in HCC. • The AUC of the model was higher than the CT-derived ECV and mFLR ratio. • The model showed a superior predictive performance than that of the ALBI score.

Gadoxetate-Enhanced MRI as a Diagnostic Tool in the Management of Hepatocellular Carcinoma: Report from a 2020 Asia-Pacific Multidisciplinary Expert Meeting

Gadoxetate magnetic resonance imaging (MRI) is widely used in clinical practice for liver imaging. For optimal use, we must understand both its advantages and limitations. This article is the outcome of an online advisory board meeting and subsequent discussions by a multidisciplinary group of experts on liver diseases across the Asia-Pacific region, first held on September 28, 2020. Here, we review the technical considerations for the use of gadoxetate, its current role in the management of patients with hepatocellular carcinoma (HCC), and its relevance in consensus guidelines for HCC imaging diagnosis. In the latter part of this review, we examine recent evidence evaluating the impact of gadoxetate on clinical outcomes on a continuum from diagnosis to treatment decision-making and follow-up. In conclusion, we outline the potential future roles of gadoxetate MRI based on an evolving understanding of the clinical utility of this contrast agent in the management of patients at risk of, or with, HCC.

Hepatectomy-Induced Alterations in Hepatic Perfusion and Function - Toward Multi-Scale Computational Modeling for a Better Prediction of Post-hepatectomy Liver Function

Liver resection causes marked perfusion alterations in the liver remnant both on the organ scale (vascular anatomy) and on the microscale (sinusoidal blood flow on tissue level). These changes in perfusion affect hepatic functions via direct alterations in blood supply and drainage, followed by indirect changes of biomechanical tissue properties and cellular function. Changes in blood flow impose compression, tension and shear forces on the liver tissue. These forces are perceived by mechanosensors on parenchymal and non-parenchymal cells of the liver and regulate cell-cell and cell-matrix interactions as well as cellular signaling and metabolism. These interactions are key players in tissue growth and remodeling, a prerequisite to restore tissue function after PHx. Their dysregulation is associated with metabolic impairment of the liver eventually leading to liver failure, a serious post-hepatectomy complication with high morbidity and mortality. Though certain links are known, the overall functional change after liver surgery is not understood due to complex feedback loops, non-linearities, spatial heterogeneities and different time-scales of events. Computational modeling is a unique approach to gain a better understanding of complex biomedical systems. This approach allows (i) integration of heterogeneous data and knowledge on multiple scales into a consistent view of how perfusion is related to hepatic function; (ii) testing and generating hypotheses based on predictive models, which must be validated experimentally and clinically. In the long term, computational modeling will (iii) support surgical planning by predicting surgery-induced perfusion perturbations and their functional (metabolic) consequences; and thereby (iv) allow minimizing surgical risks for the individual patient. Here, we review the alterations of hepatic perfusion, biomechanical properties and function associated with hepatectomy. Specifically, we provide an overview over the clinical problem, preoperative diagnostics, functional imaging approaches, experimental approaches in animal models, mechanoperception in the liver and impact on cellular metabolism, omics approaches with a focus on transcriptomics, data integration and uncertainty analysis, and computational modeling on multiple scales. Finally, we provide a perspective on how multi-scale computational models, which couple perfusion changes to hepatic function, could become part of clinical workflows to predict and optimize patient outcome after complex liver surgery.

Gadobenate dimeglumine-enhanced biliary imaging from the hepatobiliary phase can predict progression in patients with liver cirrhosis

OBJECTIVES

To determine the value of gadobenate dimeglumine (Gd-BOPTA)-enhanced biliary imaging from the hepatobiliary phase in predicting hepatic decompensation and insufficiency for patients with cirrhosis.

METHODS

This single-center retrospective study included 270 patients who underwent Gd-BOPTA-enhanced magnetic resonance imaging. The relative enhancement ratios of the biliary system (REB) and liver parenchyma (REL) in patients with normal liver function without underlying chronic liver disease and three groups of patients with Child-Pugh A, Child-Pugh B, and Child-Pugh C disease were measured. After a mean follow-up of 38.5 ± 22.5 months, prognostic factors were evaluated using the Cox proportional hazards regression model. Receiver operating characteristic (ROC) curve analyses were performed to assess the capacity of the REB and REL to predict the development of hepatic decompensation and insufficiency.

RESULTS

During the follow-up period, nine of 79 patients with Child-Pugh A disease developed hepatic decompensation. The REB was a significant predictive factor (hazard ratio (HR) = 0.40 (0.19-0.84); p = 0.016), but the REL showed no association with hepatic decompensation. Moreover, the areas under the ROC curves (AUCs) were 0.83 and 0.52 for the REB and REL, respectively. Thirty-eight of 207 patients with cirrhosis developed hepatic insufficiency. The REB was a significant predictive factor (HR = 0.24 (0.13-0.46); p < 0.0001), but the REL did not show statistically significant association with hepatic insufficiency. The AUCs were 0.82 and 0.57 for the REB and REL, respectively.

CONCLUSIONS

Gd-BOPTA-enhanced biliary imaging from the hepatobiliary phase was valuable in predicting hepatic decompensation and insufficiency for cirrhotic patients.

KEY POINTS

• Gd-BOPTA-enhanced biliary imaging was a significant predictive factor for hepatic decompensation in patients with cirrhosis. • Gd-BOPTA-enhanced biliary imaging was a significant predictive factor for hepatic insufficiency in patients with cirrhosis. • Gd-BOPTA-enhanced biliary imaging showed superior predictive values for adverse clinical outcomes compared to liver parenchymal imaging at the hepatobiliary phase.

MRI-Based Quantitation of Hepatic Steatosis Does Not Predict Hypertrophy Rate after Portal Vein Embolization in Patients with Colorectal Liver Metastasis and Normal to Moderately Elevated Fat Fraction

The aim of this study was to correlate the pre-procedural magnetic-resonance-imaging-based hepatic fat fraction (hFF) with the degree of hypertrophy after portal vein embolization (PVE) in patients with colorectal cancer liver metastases (CRCLM). Between 2011 November and 2020 February, 68 patients with CRCLM underwent magnetic resonance imaging (MRI; 1.5 Tesla) of the liver before PVE. Using T1w chemical shift imaging (DUAL FFE), the patients were categorized as having a normal (<5%) or an elevated (>5%) hFF. The correlation of hFF, age, gender, initial tumor mass, history of chemotherapy, degree of liver hypertrophy, and kinetic growth rate after PVE was investigated using multiple regression analysis and Spearman’s test. A normal hFF was found in 43/68 patients (63%), whereas 25/68 (37%) patients had an elevated hFF. The mean hypertrophy and kinetic growth rates in patients with normal vs. elevated hFF were 24 ± 31% vs. 28 ± 36% and 9 ± 9 % vs. 8 ± 10% (p > 0.05), respectively. Spearman’s test showed no correlation between hFF and the degree of hypertrophy (R = −0.04). Multivariable analysis showed no correlation between hFF, history of chemotherapy, age, baseline tumor burden, or laterality of primary colorectal cancer, and only a poor inverse correlation between age and kinetic growth rate after PVE. An elevated hFF in a pre-procedural MRI does not correlate with the hypertrophy rate after PVE and should therefore not be used as a contraindication to the procedure in patients with CRCLM.

The Assessment of Regional Liver Function Before Major Hepatectomy Using Magnetic Resonance Imaging

BACKGROUND

The liver-to-spleen signal intensity ratio (LSR) on magnetic resonance imaging with gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid has been used as a parameter to assess liver function. LSR of the future remnant liver region (FR-LSR) is included in preoperative assessment of regional liver function. The aim of this study was to investigate the predictability of post-hepatectomy liver failure (PHLF) by FR-LSR.

METHODS

Between May 2013 and May 2019, 127 patients underwent standardized EOB-MRI for diagnosis of liver tumor before major hepatectomy. The FR-LSR on EOB-MRI was calculated by a semiautomated three-dimensional volumetric analysis system. The cutoff value of FR-LSR in association with clinically relevant PHLF was determined according to the areas under the receiver operating characteristic curves. Then, FR-LSR and clinical variables were analyzed to assess the risk of clinically relevant PHLF.

RESULTS

In patients with preoperative biliary drainage, metastatic liver tumor, estimated future remnant liver volume <50%, biliary reconstruction, operation time ≥ 480 min, estimated blood loss ≥ 1000 g, blood transfusion and a FR-LSR < 2.00 were associated with clinically relevant PHLF (P < .05 for all) in univariable analysis. The liver-to-spleen signal intensity ratio of the future remnant liver region < 2.00 was the only independent risk factor for clinically relevant PHLF in multivariable risk analysis (OR, 27.90; 95% CI: 7.99-136.40; P < .05).

DISCUSSION

The present study revealed that FR-LSR calculated using a 3-dimensional volumetric analysis system was an independent risk factor for clinically relevant PHLF. The liver-to-spleen signal intensity ratio of the future remnant liver region might be a reliable preoperative parameter in liver functional assessment, enabling safe performance of major hepatectomy.

The use of neoadjuvant lobar radioembolization prior to major hepatic resection for malignancy results in a low rate of post hepatectomy liver failure

Background

Neoadjuvant yttrium-90 transarterial radioembolization (TARE) is increasingly being used as a strategy to facilitate resection of otherwise unresectable tumors due to its ability to generate both tumor response and remnant liver hypertrophy. Perioperative outcomes after the use of neoadjuvant lobar TARE remain underinvestigated.

Methods

A single center retrospective review of patients who underwent lobar TARE prior to major hepatectomy for primary or metastatic liver cancer between 2007 and 2018 was conducted. Baseline demographics, radioembolization parameters, pre- and post-radioembolization volumetrics, intra-operative surgical data, adverse events, and post-operative outcomes were analyzed.

Results

Twenty-six patients underwent major hepatectomy after neoadjuvant lobar TARE. The mean age was 58.3 years (17-88 years). 62% of patients (n=16) had primary liver malignancies while the remainder had metastatic disease. Liver resection included right hepatectomy or trisegmentectomy, left or extended left hepatectomy, and sectorectomy/segmentectomy in 77% (n=20), 8% (n=2), and 15% (n=4) of patients, respectively. The mean length of stay was 8.3 days (range, 3-33 days) and there were no grade IV morbidities or 90-day mortalities. The incidence of post hepatectomy liver failure (PHLF) was 3.8% (n=1). The median time to progression after resection was 4.5 months (range, 3.3-10 months). Twenty-three percent (n=6) of patients had no recurrence. The median survival was 28.9 months (range, 16.9-46.8 months) from major hepatectomy and 37.6 months (range, 25.2-53.1 months) from TARE.

Conclusions

Major hepatectomy after neoadjuvant lobar radioembolization is safe with a low incidence of PHLF.

Evaluation of Liver Function and the Role of Biliary Drainage before Major Hepatic Resections

Background

Prevention of posthepatectomy liver failure is a prerequisite for improving the postoperative outcome of perihilar cholangiocarcinoma. From this perspective, appropriate assessment of future liver remnant (FLR) function and the optimized preparation are mandatory.

Summary

FLR volume ratio using CT volumetry based on 3-dimensional vascular imaging is the current assessment yardstick and is sufficient for assessing a normal liver. However, in a liver with underling parenchymal disease such as fibrosis or prolonged jaundice, weighing up the degree of liver damage against the FLR volume ratio is necessary to know the real FLR function. For this purpose, the indocyanine green (ICG) clearance test, monoethylglycinexylidide (MEGX) test, liver maximum capacity (LiMAX) test, ^99mTc-labeled galactosyl human serum albumin (^99mTc-GSA) scintigraphy, albumin-bilirubin (ALBI) grade, and ALPlat (albumin × platelets) criterion are used. After the optimization of FLR function by means of portal vein embolization or associating liver partition and PVL (portal vein ligation) for staged hepatectomy (ALPPS), SPECT scintigraphy with either ^99mTc-GSA or ^99mTc-mebrofenin compensates for misestimation due to the regional heterogeneity of liver function. The role of preoperative biliary drainage has long been debated, with the associated complications having led to a lack of approval. However, the recent establishment of safety and an improvement in success rates of endoscopic biliary drainage seem to be changing the awareness of the importance of biliary drainage.

Key Messages

Appropriate selection of an assessment method is of prime importance to predict the FLR function according to the preoperative condition of the liver. Preoperative biliary drainage in patients with perihilar cholangiocarcinoma is gaining support due to the increasing safety and success rate, especially in patients who need optimization of their liver function before hepatectomy.

New frontiers in liver resection for hepatocellular carcinoma

Liver resection is one of the main curative options for early hepatocellular carcinoma (HCC) in patients with cirrhosis and is the treatment of choice in non-cirrhotic patients. However, careful patient selection is required to balance the risk of postoperative liver failure and the potential benefit on long-term outcomes. In the last decades, improved surgical techniques and perioperative management, as well as better patient selection, have enabled the indications for liver resection to be expanded. In this review, we aim to describe the main indications for liver resection in the management of HCC, its role compared to percutaneous ablation and liver transplantation in the therapeutic algorithm, as well as the recent advances in liver surgery that could be used to improve the prognosis of patients with HCC.

Prediction of post-hepatectomy liver failure using gadoxetic acid-enhanced magnetic resonance imaging for hepatocellular carcinoma with portal vein invasion

PURPOSE

Accurate prediction of post-hepatectomy liver failure (PHLF) is important in advanced hepatocellular carcinoma (HCC). We aimed to retrospectively evaluate the utility of gadoxetic acid-enhanced MRI for predicting PHLF in patients who underwent anatomic hepatectomy for HCC with portal vein invasion.

METHODS

Forty-one patients (32 men, 9 women) were included. Hepatobiliary-phase MR images were acquired 20 min after injection of gadoxetic acid using a 3D fat-suppressed T1-weighted spoiled gradient-echo sequence. Liver-spleen ratio (LSR), remnant hepatocellular uptake index (rHUI), and HUI were calculated. The severity of PHLF was defined according to the International Study Group of Liver Surgery. Differences in LSR between the resected liver and the remnant liver, and HUI and rHUI/HUI between no/mild and severe PHLF were compared using the Wilcoxon signed-rank test and Wilcoxon rank-sum test, respectively. Univariate and multivariate logistic regression analyses were performed to identify predictors of severe PHLF. Areas under the receiver operating characteristic curves (AUCs) of rHUI and rHUI/HUI were calculated for predicting severe PHLF.

RESULTS

Nine patients developed severe PHLF. LSR of the remnant liver was significantly higher than that of the resected liver (P < 0.001). Severe PHLF demonstrated significantly lower rHUI (P < 0.001) and rHUI/HUI (P < 0.001) compared with no/mild PHLF. Multivariate logistic regression analysis showed that decreased rHUI (P = 0.012, AUC=0.885) and rHUI/HUI (P = 0.002, AUC=0.852) were independent predictors of severe PHLF.

CONCLUSION

Gadoxetic acid-enhanced MRI can be a promising noninvasive examination for assessing global and regional liver function, allowing estimation of the functional liver remnant and accurate prediction of severe PHLF before hepatic resection.

Level of total bilirubin in the bile of the future remnant liver of patients with obstructive jaundice undergoing hepatectomy predicts postoperative liver failure

BACKGROUND

We investigated whether the daily level of total bilirubin in the bile (LTB) excreted from the future remnant liver (FRL) can predict post-hepatectomy liver failure (PHLF) in patients with obstructive jaundice undergoing hepatectomy.

METHODS

Seventy-four patients who underwent biliary drainage and collection of bile juice from the FRL before undergoing right hepatectomy or right/left trisectionectomy with bile duct resection were included. The LTB from the FRL (mg/d) was calculated as the volume of the bile (dL) per day multiplied by the density of total bilirubin in the bile (mg/dL). We compared patients' characteristics with or without PHLF, which was defined as the total serum bilirubin level remaining >10 mg/dL after postoperative day 10. Then, pre- and intraoperative factors related to PHLF were examined.

RESULTS

PHLF was observed in six patients. LTB was significantly lower in the PHLF group. The LTB cut-off value for predicting PHLF, as determined using the receiver operating characteristic curve, was 56 mg/d. On multivariate analysis, LTB was found to be an independent risk factor for PHLF (P = .01, OR 35.88).

CONCLUSIONS

LTB may be a potential functional assessment in jaundiced patients before right hepatectomy and right/left trisectionectomy.

Consistency of hepatocellular gadoxetic acid uptake in serial MRI examinations for evaluation of liver function

PURPOSE

To assess the consistency of liver enhancement in gadoxetic acid-enhanced magnetic resonance imaging (MRI) over serial examinations.

METHODS

This retrospective study included 554 patients who underwent at least 2 serial gadoxetic acid-enhanced MRI scans at either 1.5 or 3.0 Tesla at our institution between 2014 and 2018. Signal intensities (SI) were measured on T1-weighted images before and approx. 20 min after intravenous injection of gadoxetic acid. Relative enhancement (RE) of the liver, liver-to-spleen SI ratio (LSR), and liver-to-muscle SI ratio (LMR) were calculated. Means were compared with the paired t test, Greenhouse-Geisser test, and linear mixed model analysis, accordingly. Multiple linear regression analysis was used to elucidate possible predictors of RE and bivariate correlation analysis of patient age with RE was performed.

RESULTS

No statistically significant difference in RE, LSR, and LMR between two consecutive MRI scans was found when tested with paired t test or Greenhouse-Geisser test (n = 554, 519, and 554, respectively), while the latter revealed a statistically significant difference between the first and fourth MRI scan which was not confirmed in the linear mixed model. Patient age correlated negatively with RE of the liver (p = 0.002), LSR (p < 0.001), and LMR (p = 0.006).

CONCLUSIONS

Relative enhancement of the liver in the hepatobiliary phase of gadoxetic acid-enhanced MRI is consistent over successive examinations, different scanner types, and field strengths while correlating negatively with age, which further underscores the validity of gadoxetic acid-enhanced MRI as an imaging-based liver function test.

Prediction of Posthepatectomy Liver Failure: MRI With Hepatocyte-Specific Contrast Agent Versus Indocyanine Green Clearance Test

OBJECTIVE

The objective of our study was to identify whether quantitative measurements from gadoxetic acid-enhanced MRI are useful for predicting posthepatectomy liver failure (PHLF) in patients with hepatocellular carcinoma (HCC) compared with and in combination with future remnant liver volume (FRLV) and an indocyanine green (ICG) clearance test.

MATERIALS AND METHODS

Preoperative gadoxetic acid-enhanced MR images were retrospectively evaluated in 73 patients who underwent anatomic liver resection for HCC between 2011 and 2013. For quantitative measurement of hepatocyte function, relative liver enhancement (RLE) and remnant hepatocyte uptake index (rHUI) were measured using hepatobiliary phase MR images. FRLV was determined using measurements from preoperative CT scans. Univariate and multivariate analyses of measurements from gadoxetic acid-enhanced MRI, ICG clearance tests, and FRLV for finding predictors of PHLF were performed. To compare the diagnostic performance of predictors, ROC analyses were also performed.

RESULTS

Eighteen (25%) of 73 patients met the criteria for PHLF. Univariate analysis revealed that all measurements related to MRI including RLE, rHUI, ICG clearance, and FRLV were significantly associated with PHLF. Multivariate analysis showed that RLE, FRLV, ICG-plasma disappearance rate (ICG-PDR), rHUI, and rHUI corrected for body weight (rHUI-BW) were independent predictors of PHLF (p = 0.011, p = 0.034, p = 0.003, p < 0.001, and p = 0.001, respectively). In ROC analyses, AUCs of rHUI and rHUI-BW were larger than those of other independent predictors; the differences were statistically significant (for rHUI-BW vs RLE, ICG-PDR, and FRLV, p = 0.016, 0.007, and 0.046, respectively; for rHUI vs RLE and ICG-PDR, p = 0.045 and 0.016, respectively).

CONCLUSION

Measurements from gadoxetic acid-enhanced MRI predicted PHLF better than the ICG clearance test in patients with HCC who underwent hepatectomy.

Evaluation of liver function using gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid enhanced magnetic resonance imaging based on a three-dimensional volumetric analysis system

Background

Magnetic resonance imaging with gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (EOB-MRI) is a diagnostic modality for liver tumors. Three-dimensional (3D) volumetric analysis systems using EOB-MRI data are used to simulate liver anatomy for surgery. This study was conducted to investigate clinical utility of a 3D volumetric analysis system on EOB-MRI to evaluate liver function.

Methods

Between August 2014 and December 2015, 181 patients underwent laboratory and radiological exams as standardized preoperative evaluation for liver surgery. The liver-spleen contrast-enhanced ratio (LSR) was measured by a semi-automated 3D volumetric analysis system on EOB-MRI. First, the inter-evaluator variability of the calculated LSR was evaluated. Additionally, a subset of liver surgical specimens was evaluated histologically by using immunohistochemical staining. Finally, the correlations between the LSR and grading systems of liver function, laboratory data, or histological findings were analyzed.

Results

The inter-evaluator correlation coefficient of the measured LSR was 0.986. The mean LSR was significantly correlated with the Child–Pugh score (p = 0.014) and the ALBI score (p < 0.001). Significant correlations were also observed between the LSR and indocyanine green retention rate at 15 min (r = − 0.601, p < 0.001), between the LSR and liver fibrosis stage (r = − 0.556, p < 0.001), and between the LSR and liver steatosis grade (r = − 0.396, p < 0.001).

Conclusion

The LSR calculated by a 3D volumetric analysis system on EOB-MRI was highly reproducible and was shown to be correlated with liver function parameters and liver histology. These data suggest that this imaging modality can be a reliable tool to evaluate liver function.

Electronic supplementary material

The online version of this article (10.1007/s12072-018-9874-x) contains supplementary material, which is available to authorized users.

Liver Function Assessment Using Technetium 99m-Galactosyl Single-Photon Emission Computed Tomography/CT Fusion Imaging: A Prospective Trial

BACKGROUND

The prediction of postoperative liver function remains a largely subjective practice based on CT volumetric analysis. However, future liver volume after a hepatectomy is not the only factor that contributes to postoperative liver function and outcomes.

STUDY DESIGN

In this prospective trial, 185 consecutive patients who underwent liver operations between 2014 and 2015 were studied. Volumetric and functional rates of remnant liver were measured using technetium 99m-galactosyl human serum albumin single-photon emission computed tomography/CT fusion imaging to evaluate post-hepatectomy remnant liver function. Remnant indocyanine green clearance rate using galactosyl (KGSA) (KGSA × functional rate) was used to predict future remnant liver function. Hepatectomy was considered safe for patients with remnant KGSA values ≥0.05, and the primary end point was to determine the accuracy and reliability of this criteria. The prediction of the 90-day major complication and mortality rates was assessed.

RESULTS

Median hospital stay was 9 days and median ICU stay was 1 day, with only 1 in-hospital death (90-day mortality rate 0.5%). Overall morbidity rate evaluated according to the Clavien-Dindo classification was 9%. For post-hepatectomy liver failure definitions, the International Study Group of Liver Surgery definition was fulfilled in 14 patients (8%), with the majority being grade B (50%), compared with 2 patients (1%) fulfilling the "50-50" criteria, and 0 patients (0%) fulfilling the _PeakBili >7 criteria.

CONCLUSIONS

Results of this study showed that remnant KGSA provided information that allowed us to predict remnant liver function. This information will be important for surgeons when deciding on a treatment plan for patients with liver diseases. (ClinicalTrials.gov ID: NCT02013895).

Gd-EOB-DTPA based magnetic resonance imaging for predicting liver response to portal vein embolization

AIM

To evaluate the correlation between degree of kinetic growth (kGR) of the liver following portal vein embolization (PVE) liver and the enhancement of the during the hepatobiliary phase of contrast administration and to evaluate if the enhancement can be used to predict response to PVE prior to the procedure.

METHODS

Seventeen patients were consented for the prospective study. All patients had an MR of the abdomen with Gd-EOB-DTPA. Fourteen patients underwent PVE. The correlation between the kGR of the liver and the degree of enhancement was evaluated with linear regression (strong assumptions) and Spearman’s correlation test (rank based, no assumptions). The correlation was examined for the whole liver, segments I, VIII, VII, VI, V, IV, right liver and left liver.

RESULTS

There was no correlation between the degree of enhancement during the hepatobiliary phase and kGR for any segment, lobe of the liver or whole liver (P = 0.19 to 0.91 by Spearman’s correlation test).

CONCLUSION

The relative enhancement of the liver during the hepatobiliary phase with Gd-EOB-DTPA cannot be used to predict the liver response to PVE.