Liver metabolism depends on the mechanical interplay between the solid tissue matrix and blood vessels, making shear modulus and pressure important variables of hepatic homeostasis. While shear modulus can be quantified by magnetic resonance elastography (MRE), pressure is not available through noninvasive imaging. We propose combined determination of liver deformation and shear modulus using volumetric MRI and MRE for noninvasive portal pressure assessment. Volumetric MRI and multifrequency MRE were performed in five ex vivo rat livers at different portal pressures. A similar imaging protocol was used to examine eleven healthy volunteers after overnight fasting in two respiratory states and after ingestion of 1.5 L of water. Models derived from ex vivo rat data served to scale human liver volumetric strain multiplied by differential shear modulus obtained from MRE to portal pressure. After water intake, liver volume expanded by 3 % (Interquartile range [IQR], 1.3-6.0; p < 0.001) and shear modulus increased by 0.12 kPa (IQR, 0.08-0.26; p = 0.001), while deep inhalation had mixed effects (p > 0.05). Positive and negative volumetric strains were associated with stiffening and softening, respectively, leading to a consistent increase in portal pressure of 0.2 to 0.3 kPa (IQR, 0.07-0.41) for inhalation and water ingestion. In conclusion, volumetric strain analysis combined with MRE in different scenarios of in vivo liver deformation and calibration with controlled ex vivo experiments allowed assessment of portal pressure changes. In clinical applications, combined MRE and volumetric MRI after inspiration or water ingestion could provide mechanical contrast for assessing hepatic pressure-related diseases. STATEMENT OF SIGNIFICANCE: Using 3D MRI and MR elastography, this study introduces trained image segmentation and registration based quantification of liver volumetric strain in combination with shear modulus measurement for non invasive assessment of portal venous pressure. Volumetric strain and tissue stiffening due to altered portal venous pressure are quantified in ex vivo rat livers and under physiological conditions in healthy volunteers. It is shown that the new method is sensitive to subtle changes in in vivo portal pressure in the range of 0.2 to 0.3 kPa due to deep inspiration or water intake. Our method offers a diagnostic tool for liver pressure related diseases by providing a better understanding of the liver shear modulus and its relationship to portal venous pressure.

Although various self-expandable metallic stents (SEMSs) for malignant hilar biliary obstruction (MHBO) have been introduced, the optimal SEMS for MHBO has not yet been established.

This study aimed to evaluate outcomes of the transpapillary placement of an uncovered laser-cut SEMS with an ultra-thin delivery sheath (YABUSAME) for MHBO.

This multicenter, prospective study was conducted in 11 hospitals for 10 months (from March 2022 to December 2022). The primary outcome was the stent patency rate at 6 months. Key secondary outcomes were the technical success rate, clinical success rate, time to recurrent biliary obstruction (RBO), overall survival (OS), and adverse events.

Of 45 enrolled patients, 43 patients underwent biliary drainage, including 42 patients who underwent YABUSAME placement; 66.7% of patients received chemotherapy, and 60% had previously undergone biliary drainage. Drainage methods were partial stent-in-stent, side-by-side, and unilateral in 65.1%, 7.0%, and 27.9% of patients, respectively. Technical and clinical success rates were 93.2% (41/45) and 79.1% (34/45), respectively. The incidence rate of early postprocedural adverse events was 2.2%. The stent patency rate at 6 months was 55.3%. The median time to RBO was 231 days. The median OS was 125 days.

This study showed that the primary outcome, the 6-month stent patency rate, exceeded the expected rate of 55%, which indicates the efficacy of YABUSAME placement for MHBO.

Colorectal cancer most commonly metastasizes to the liver. While various treatment strategies have been developed, surgical management of these patients has vital implications on the prognosis and survival of this group of patients. There remains a need for a consensus guideline regarding the surgical evaluation and management of patients with colorectal liver metastases (CRLM).

This review article is a consensus guideline established by the members of the AHPBA Professional Standards Committee, as an amalgamation of existent literature and a guide to surgeons managing this complex disease.

These guidelines reports the benefits and shortcomings of various diagnostic modalities including imaging and next-generation sequencing in the management of patients with CRLM. While surgery has established survival benefits in patients with resectable disease, this report notes the importance of treatment sequencing with non-surgical modalities as well as between colon and liver resection. Finally, the guidelines address the various treatment modalities for patients with unresectable disease, that may have significant impact on survival.

CRLM is a complex diagnosis which warrants multidisciplinary approach with early surgical involvement in both assessment and management of the disease, to optimize patient outcomes and survival.

Accurate assessment of the future liver remnant (FLR) is crucial for predicting the risk of post-hepatectomy liver failure (PHLF). This survey aims to evaluate the current practices of liver surgeons regarding FLR volumetry and its clinical use.

A cross-sectional survey was conducted among 212 liver surgeons to assess their use of FLR volumetry and associated methodologies. The survey consisted of 40 questions distributed in five sections covering multiple aspects of FLR volumetry.

Ninety percent of respondents utilize preoperative FLR volumetry. However, there is significant variability in the methods used for FLR calculation and the thresholds for safe liver resection, which deviate from the proposed 20/30/40 % rule. Before right hepatectomy, 21 % of respondents indicated that they rarely or never utilise volumetry. Extended resections are the surgical procedures in which volumetry is most frequently employed. Furthermore, the kinetic growth rate is not widely adopted in clinical decision making.

This survey highlights the widespread use of FLR volumetry, but also reveals substantial variation in its application. This demonstrates a lack of evidence or guidelines regarding the appropriate use of FLR volumetry.

Compare the efficacy and procedural efficiency of central vascular plug-assisted portal vein embolization (PVE) with absolute ethanol compared to selective PVE.

Between 2016 and 2023, patients who underwent ipsilateral percutaneous transhepatic PVE were included. Selective PVE involves serial cannulation and embolization of portal veins. Central vascular plug-assisted PVE involves deploying a vascular plug at the main portal vein with embolization. Recorded data includes patient demographics, disease diagnosis, volumetry, embolization procedure, biliary drainage, surgery, and measures of future liver remnant hypertrophy (relative hypertrophy, degree of hypertrophy, and kinetic growth rate).

The cohort comprised of 30 patients (cohort mean age 64±9 years old, females n=14) of which 17 (57%) patients underwent central vascular plug-assisted PVE. Indications for PVE were predominately (87%, 26/30) due to bile duct cancer. Volumetric changes between central vascular plug-assisted PVE and selective PVE were not different between the two groups (DH 13%±5 vs 11%±4, p=0.21; and KGR 3%/week ± 2 vs 2%/week ± 2, p=0.27, respectively). Overall procedure times were shorter for central vascular plug-assisted PVE (45±20 minutes vs 112±34 minutes; p<0.001). Two adverse events occurred in selective PVE, while none in central vascular plug-assisted PVE. There was no difference in rates of surgery or no surgery for both methods (p=0.07).

Central vascular plug-assisted PVE with absolute ethanol effectively induced FLR hypertrophy, and significantly reduced procedure times due to faster embolization and simpler technique.

Post-hepatectomy liver failure is a major cause of mortality, where future liver remnant (FLR) is the key controllable factor. Recommended minimum FLR is influenced by quality of liver parenchyma. Historical research has often failed to include Māori and Pacific Island (PI) populations despite worse health outcomes. Liver analysis by ethnicity is one such example of this. The aims were to determine digital FLR for various anatomical hepatectomies, investigate any correlations between computed tomography (CT) hepatic textural analysis and body mass index (BMI); and assess the variance of these relationships for different ethnicities.

One hundred and fifty-one patients who underwent abdominal CT scans at Burwood Hospital, Christchurch were retrospectively analysed. Māori and PI patients were selectively recruited to represent New Zealand's diversity. Liver volumetry, segmental ratio, and intra-hepatic fat deposits (IHFD) per ethnicity were examined.

Median age of the cohort was 66 (19-95) and 75 (50%) were males. 68%, 23% and 9% patients identified as being European, Māori/PI and Asian, respectively. No statistically significant difference in volume or segment/total volume ratio were noted across different ethnicities. Obese patients had higher IHFD compared with overweight and normal BMI groups. When stratified across ethnic groups, higher IHFD were observed in Asian compared with Māori/PI populations, despite lower BMI.

No significant variances in liver volumetry were found across different ethnic groups in New Zealand. However association between BMI and IHFD varied across different ethnic cohorts. Consequently, knowledge of liver volumetry is not enough; patient liver quality and ethnicity should considered for hepatic-surgery planning.

Following major liver resection, posthepatectomy liver failure (PHLF) is associated with a high mortality rate. As there is no therapy for PHLF available, avoidance remains the main goal. A sufficient future liver remnant (FLR) is one of the most important factors to reduce the risk for PHLF; however, it is not known which patients benefit of volumetric assessment prior to major surgery.

A retrospective, bi-institutional cohort study was conducted including all patients who underwent major hepatectomy (extended right hepatectomy, right hepatectomy, extended left hepatectomy and left hepatectomy) between 2010 and 2023.

A total of 1511 major hepatectomies were included, with 29.4 % of patients undergoing FLR volume assessment preoperatively. Overall, PHLF B/C occurred in 9.8 % of cases. Multivariate analysis identified diabetes mellitus, extended right hepatectomy, perihilar cholangiocarcinoma (pCCA), gallbladder cancer (GBC) and cirrhosis as significant risk factors for PHLF B/C. High-risk patients (with one or more risk factors) had a 15 % overall incidence of PHLF, increasing to 32 % with a FLR <30 %, and 13 % with an FLR of 30-40 %. Low-risk patients with a FLR <30 % had a PHLF rate of 21 %, which decreased to 8 % and 5 % for FLRs of 30-40 % and >40 %, respectively. For right hepatectomy, the PHLF rate was 23 % in low-risk and 38 % in high-risk patients with FLR <30 %.

Patients scheduled for right hepatectomy and extended right hepatectomy should undergo volumetric assessment of the FLR. Volumetry should always be considered before major hepatectomy in patients with risk factors such as diabetes, cirrhosis, GBC and pCCA. In high-risk patients, a FLR cut-off of 30 % may be insufficient to prevent PHLF, and additional liver function assessment should be considered.

Perihilar cholangiocarcinoma (pCCA) is a highly lethal hepatobiliary cancer. Radical resection offers the best chance for extended survival, but the efficacy of left-sided hepatectomy (LH) versus right-sided hepatectomy (RH) remains controversial.

A systematic review and meta-analysis of non-randomized cohort studies comparing LH and RH in patients with resectable pCCA was conducted. Subanalyses were performed based on year of publication, region, number of cases and Bismuth classification (BC) ≥ III.

Nineteen studies involving 3838 patients were included, with 1779 (46 %) undergoing LH and 2059 (54 %) undergoing RH. LH was associated with increased overall survival (OS) in subgroup analysis of studies reporting hazard ratios (HR) (logHR 0.59; p = 0.04). LH showed higher rates of arterial resection (14 % vs. 1 %), transfusion (51 % vs. 41 %), operation time (MD 31.44 min), and bile leakage (21 % vs. 18 %), but lower rates of post-hepatectomy liver failure (9 % vs. 21 %) and 90-day mortality (8 % vs 16 %). Three-year disease-free survival rates increased in Western centers but decreased in Eastern centers.

LH is linked to higher OS in this analysis but is a more demanding technique. Resection side decision should consider several factors, including future liver remnant, tumor location, vascular involvement, and surgical expertise.

The liver, the largest gland in a wedge-shape, is situated in the right hypochondrium, and exhibits variation in its lobes. Knowledge of variations in the lobes of the liver is crucial for accurate radiological diagnosis and successful abdominal surgeries. The elongation of the left lobe of the liver has gained significant attention in segmentectomy and liver transplant surgeries. During October and November 2023, cross-sectional observational research was done on 53 human cadaveric liver specimens obtained from different medical colleges in Gujarat, India. The livers were meticulously examined to determine the prevalence of Beaver tail liver and measurements such as length, breadth, and thickness were recorded and statistically analyzed. The study revealed that out of the 53 livers examined, 29 (54.72%) were classified as normal, while 19 (35.85%) fell into Netter's type 2 to 7 based on Netter's classification. Interestingly, 5 (09.43%) livers exhibited an elongated left lobe, referred to as a "sliver liver," which did not fit into any of the Netter's types. The beaver tail liver was found to be longer and broader compared to normal liver of the same size and weight (p<0.001). This study highlights the wide range of variations that can be observed in the lobes of the liver. The findings of this study will serve as a valuable resource for radiologists, anatomists, and surgeons, aiding them in accurate diagnoses and surgical procedures, thus minimizing the risk of misdiagnosis.

Metastatic colorectal cancer (mCRC) is a major cause of cancer-related death, with a 5-year relative overall survival of up to 20%. The liver is the most common site of distant metastasis in colorectal cancer (CRC), with about 50% of CRC patients metastasizing to their liver over the course of their disease. Complete liver resection is the primary modality of treatment for resectable colorectal cancer liver metastasis (CRLM), with an overall 5-year survival rate of up to 58%. However, only 15% to 20% of patients with CRLM are deemed suitable for resection at presentation. For unresectable diseases, the median survival of patients remains low even with the best chemotherapy. In recent decades, the management of CRLM has continued to evolve with the expansion of resection criteria, novel targeted systemic therapies, and improved locoregional therapies. However, due to the heterogeneity of the CRC patient population, the optimal evaluation of treatment options for CRLM remains complex. Therefore, effective management requires a multidisciplinary team to help define resectability and devise a personalized treatment approach, from the initial diagnosis to the final treatment.

Background and Objectives: Preoperative right portal vein embolization (RPVE) is often attempted before right hepatectomy for liver tumors to increase the future remnant liver volume (FRLV). Although many factors affecting FRLV have been discussed, few studies have focused on the ratio of the cross-sectional area of the right portal vein to that of the left portal vein (RPVA/LPVA). The aim of the present study was to evaluate the effect of RPVA/LPVA on predicting FRLV increase after RPVE. Materials and Methods: The data of 65 patients who had undergone RPVE to increase FRLV between 2004 and 2021 were investigated retrospectively. Using computed tomography scans, we measured the total liver volume (TLV), FRLV, the proportion of FRLV relative to TLV (FRLV%), the increase in FRLV% (ΔFRLV%), and RPVA/LPVA twice, immediately before and 2-3 weeks after RPVE; we analyzed the correlations among those variables, and determined prognostic factors for sufficient ΔFRLV%. Results: Fifty-four patients underwent hepatectomy. Based on the cut-off value of RPVA/LPVA, the patients were divided into low (RPVA/LPVA ≤ 1.20, N = 30) and high groups (RPVA/LPVA > 1.20, N = 35). The ΔFRLV% was significantly greater in the high group than in the low group (9.52% and 15.34%, respectively, p < 0.001). In a multivariable analysis, RPVA/LPVA (HR = 20.368, p < 0.001) was the most significant prognostic factor for sufficient ΔFRLV%. Conclusions: RPVE was more effective in patients with higher RPVA/LPVA, which is an easily accessible predictive factor for sufficient ΔFRLV%.

A right- or left-sided liver resection can be considered in about half of patients with perihilar cholangiocarcinoma (pCCA), depending on tumor location and vascular involvement. This study compared postoperative mortality and long-term survival of right- versus left-sided liver resections for pCCA.

Patients who underwent major liver resection for pCCA at 25 Western centers were stratified according to the type of hepatectomy-left, extended left, right, and extended right. The primary outcomes were 90-day mortality and overall survival (OS).

Between 2000 and 2022, 1701 patients underwent major liver resection for pCCA. The 90-day mortality was 9% after left-sided and 18% after right-sided liver resection (p < 0.001). The 90-day mortality rates were 8% (44/540) after left, 11% (29/276) after extended left, 17% (51/309) after right, and 19% (108/576) after extended right hepatectomy (p < 0.001). Median OS was 30 months (95% confidence interval [CI] 27-34) after left and 23 months (95% CI 20-25) after right liver resection (p < 0.001), and 33 months (95% CI 28-38), 27 months (95% CI 23-32), 25 months (95% CI 21-30), and 21 months (95% CI 18-24) after left, extended left, right, and extended right hepatectomy, respectively (p < 0.001). A left-sided resection was an independent favorable prognostic factor for both 90-day mortality and OS compared with right-sided resection, with similar results after excluding 90-day fatalities.

A left or extended left hepatectomy is associated with a lower 90-day mortality and superior OS compared with an (extended) right hepatectomy for pCCA. When both a left and right liver resection are feasible, a left-sided liver resection is preferred.

Post-hepatectomy liver failure is a source of morbidity and mortality after major hepatectomy and is related to the volume of the future liver remnant. The accuracy of a clinician's ability to visually estimate the future liver remnant without formal computed tomography liver volumetry is unknown.

Twenty physicians in diagnostic radiology, interventional radiology, and hepatopancreatobiliary surgery reviewed 20 computed tomography scans of patients without underlying liver pathology who were not scheduled for liver resection. We evaluated clinician accuracy to estimate the future liver remnant for 3 hypothetical major hepatic resections: left hepatectomy, right hepatectomy, and right trisectionectomy. The percent-difference between the mean and actual computed tomography liver volumetry (mean percent difference) was tested along with specialty differences using mixed-effects regression analysis.

The actual future liver remnant (computed tomography liver volumetry) remaining after a hypothetical left hepatectomy ranged from 59% to 75% (physician estimated range: 50%-85%), 23% to 40% right hepatectomy (15%-50%), and 13% to 29% right trisectionectomy (8%-39%). For right hepatectomy, the mean future liver remnant was overestimated by 95% of clinicians with a mean percent difference of 22% (6%-45%; P < .001). For right trisectionectomy, 90% overestimated the future liver remnant by a mean percent difference of 25% (6%-50%; P < .001). Hepatopancreatobiliary surgeons overestimated the future liver remnant for proposed right hepatectomy and right trisectionectomy by a mean percent difference of 25% and 34%, respectively. Based on years of experience, providers with <10 years of experience had a greater mean percent difference than providers with 10+ years of experience for hypothetical major hepatic resections, but was only significantly higher for left hepatectomy (9% vs 6%, P = .002).

A clinician's ability to visually estimate the future liver remnant volume is inaccurate when compared to computed tomography liver volumetry. Clinicians tend to overestimate the future liver remnant volume, especially in patients with a small future liver remnant where the risk of posthepatectomy liver failure is greatest.

Accurate evaluation of postoperative liver regeneration is essential to prevent postoperative liver failure.

To analyze the predictors that affect liver regeneration after hemi-hepatectomy.

Patients who underwent hemi-hepatectomy in Hangzhou First People's Hospital and Hangzhou Shulan Hospital from January 2016 to December 2021 were enrolled in this study. The regeneration index (RI) was calculated by the following equation: RI = [(postoperative total liver volume {TLVpost} - future liver remnant volume {FLRV}/FLRV] × 100 %. Hepatic dysfunction was defined according to the "TBilpeak>7" standard, which was interpreted as (peak) total bilirubin (TBil) >7.0 mg/dL. Good liver regeneration was defined solely when the RI surpassed the median with hepatic dysfunction. Logistic regression analyses were performed to estimate prognostic factors affecting liver regeneration.

A total of 153 patients were enrolled, with 33 in the benign group and 120 patients in the malignant group. In the entire study population, FLRV% [OR 4.087 (1.405-11.889), P = 0.010], international normalized ratio (INR) [OR 2.763 (95%CI, 1.008-7.577), P = 0.048] and TBil [OR 2.592 (95%CI, 1.177-5.710), P = 0.018] were independent prognostic factors associated with liver regeneration. In the benign group, only the computed tomography (CT) parameter FLRV% [OR, 11.700 (95%CI, 1.265-108.200), P = 0.030] predicted regeneration. In the malignant group, parenchymal hepatic resection rate (PHRR%) [OR 0.141 (95%CI, 0.040-0.499), P = 0.002] and TBil [OR 3.384 (95%CI, 1.377-8.319), P = 0.008] were independent prognostic factors.

FLRV%, PHRR%, TBil and INR were predictive factors associated with liver regeneration.

This study aims to develop a semiautomated pipeline and user interface (LiVaS) for rapid segmentation and labeling of MRI liver vasculature and evaluate its time efficiency and accuracy against manual reference standard. Retrospective feasibility pilot study. Liver MR images from different scanners from 36 patients were included, and 4/36 patients were randomly selected for manual segmentation as referenced standard. The liver was segmented in each contrast phase and masks registered to the pre-contrast segmentation. Voxel-wise signal trajectories were clustered using the k-means algorithm. Voxel clusters that best segment the liver vessels were selected and labeled by three independent radiologists and a research scientist using LiVaS. Segmentation times were compared using a paired-sample t-test on log-transformed data. The agreement was analyzed qualitatively and quantitatively using DSC for hepatic and portal vein segmentations. The mean segmentation time among four readers was significantly shorter than manual (3.6 ± 1.4 vs. 70.0 ± 29.2 min; p < 0.001), even when using a higher number of clusters to enhance accuracy. The DSC for portal and hepatic veins reached up to 0.69 and 0.70, respectively. LiVaS segmentations were overall of good quality, with variations in performance related to the presence/severity of liver disease, acquisition timing, and image quality. Our semi-automated pipeline was robust to different MRI vendors in producing segmentation and labeling of liver vasculature in agreement with expert manual annotations, with significantly higher time efficiency. LiVaS could facilitate the creation of large, annotated datasets for training and validation of neural networks for automated MRI liver vascularity segmentation. HIGHLIGHTS: Key Finding: In this pilot feasibility study, our semiautomated pipeline for segmentation of liver vascularity (LiVaS) on MR images produced segmentations with simultaneous labeling of portal and hepatic veins in good agreement with the manual reference standard but at significantly shorter times (mean LiVaS 3.6 ± 1.4 vs. mean manual 70.0 ± 29.2 min; p < 0.001). Importance: LiVaS was robust in producing liver MRI vascular segmentations across images from different scanners in agreement with expert manual annotations, with significant ly higher time efficiency, and therefore potential scalability.

Previous studies have suggested the utility of an indocyanine green plasma clearance rate of the future liver remnant (FLR) (ICGK-F) ≥0.05 in hepatobiliary resection to reduce the surgical risk. The present study aimed to verify whether future liver remnant size rather than ICGK-F matters in extended hepatobiliary resection.

Between 2004 and 2021, patients who underwent right hepatic trisectionectomy with bile duct resection were included. The effect of the FLR volume-to-body weight ratio (FLR/BW) and ICGK-F on posthepatectomy liver failure was evaluated along with other parameters.

Among 91 study patients, the median ICGK-F, FLR, and FLR/BW were 0.057 (range, 0.027-0.099), 392 mL (145-705), and 0.78% (0.40-1.37), respectively. Posthepatectomy liver failure occurred in 23 patients. The incidence was 10 (40%) in 25 patients with an ICGK-F <0.05 and 12 (18%) in 65 patients with an ICGK-F ≥0.05 (P = .053); 13 (52%) in 25 patients with a FLR/BW <0.65% and 10 (15%) in 66 patients with a FLR/BW ≥0.65% (P = .001). Multivariate analysis showed that a FLR/BW <0.65% (odds ratio, 11.7; P = .005), age ≥65 years (odds ratio, 31.7; P < .001), and blood loss ≥25 mL/kg (odds ratio, 22.1; P = .004) were independent predictors of posthepatectomy liver failure, but ICGK-F <0.05 was not (P = .499). According to the meeting number of 3 factors, posthepatectomy liver failure incidence was 0 of 22 (0%) in patients with 0 factors, 6 of 43 (14%) in patients with 1, and 17 of 26 (65%) in patients with 2 or 3 (P < .001).

A FLR/BW ≥0.65% may serve as a volumetric basis to reduce posthepatectomy liver failure after extended hepatobiliary resection.

The liver is one the largest organs in the abdomen and the most frequent site of metastases for gastrointestinal tumors. Surgery on this complex and highly vascularized organ can be associated with high morbidity even in experienced hands. A thorough understanding of liver anatomy is key to approaching liver surgery with confidence and preventing complications. The aim of this quiz is to provide an active learning tool for a comprehensive understanding of liver anatomy and its integration into clinical practice.

The earliest and most accurate detection of the pathological manifestations of hepatic diseases ensures effective treatments and thus positive prognostic outcomes. In clinical settings, screening and determining the extent of a pathology are prominent factors in preparing remedial agents and administering appropriate therapeutic procedures. Moreover, in a patient undergoing liver resection, a realistic preoperative simulation of the subject-specific anatomy and physiology also plays a vital part in conducting initial assessments, making surgical decisions during the procedure, and anticipating postoperative results. Conventionally, various medical imaging modalities, e.g., computed tomography, magnetic resonance imaging, and positron emission tomography, have been employed to assist in these tasks. In fact, several standardized procedures, such as lesion detection and liver segmentation, are also incorporated into prominent commercial software packages. Thus far, most integrated software as a medical device typically involves tedious interactions from the physician, such as manual delineation and empirical adjustments, as per a given patient. With the rapid progress in digital health approaches, especially medical image analysis, a wide range of computer algorithms have been proposed to facilitate those procedures. They include pattern recognition of a liver, its periphery, and lesion, as well as pre- and postoperative simulations. Prior to clinical adoption, however, software must conform to regulatory requirements set by the governing agency, for instance, valid clinical association and analytical and clinical validation. Therefore, this paper provides a detailed account and discussion of the state-of-the-art methods for liver image analyses, visualization, and simulation in the literature. Emphasis is placed upon their concepts, algorithmic classifications, merits, limitations, clinical considerations, and future research trends.

Partial liver resections are routinely performed in living donor liver transplantation and to debulk tumours in liver malignancies, but surgical decisions on vessel reconstruction for adequate inflow and outflow are challenging. Pre-operative evaluation is often limited to radiological imaging, which fails to account for post-resection haemodynamic alterations. Substantial evidence suggests post-surgical increase in local volume flow rate enhances shear stress, signalling hepatic regeneration, but excessive shear stress has been postulated to result in small for size syndrome and liver failure. Predicting haemodynamic alterations throughout the liver is particularly challenging due to the dendritic architecture of the vasculature, spanning several orders of magnitude in diameter. Therefore, we developed a mathematical lumped parameter model with realistic heterogeneities capturing inflow/outflow of the human liver to simulate acute perfusion alterations following surgical resection. Our model is parametrized using clinical measurements, relies on a single free parameter and accurately captures established perfusion characteristics. We quantify acute changes in volume flow rate, flow speed and wall shear stress following variable, realistic liver resections and make comparisons with the intact liver. Our numerical model runs in minutes and can be adapted to patient-specific anatomy, providing a novel computational tool aimed at assisting pre- and intra-operative surgical decisions for liver resections.

Liver resection is the first curative option for most hepatic primary and secondary malignancies. However, post-hepatectomy liver failure (PHLF) still represents a non-negligible postoperative complication, embodying the most frequent cause of hepatic-related mortality. In the absence of a specific treatment, the most effective way to deal with PHLF is its prevention through a careful preoperative assessment of future liver remnant (FLR) volume and function. Apart from the clinical score and classical criteria to define the safe limit of resectability, new imaging modalities have shown their ability to assist surgeons in planning the best operative strategy with a precise estimation of the FLR amount. New technologies leading to liver and tumor 3D reconstruction may guide the surgeon along the best resection planes combining the least liver parenchymal sacrifice with oncological appropriateness. Integration with imaging modalities, such as hepatobiliary scintigraphy, capable of estimating total and regional liver function, may bring about a decrease in postoperative complications. Magnetic resonance imaging with hepatobiliary contrast seems to be predominant since it simultaneously integrates hepatic function and volume information along with a precise characterization of the target malignancy.

To explore whether intravoxel incoherent motion (IVIM) parameters could evaluate liver regeneration preoperatively.

A total of 175 HCC patients were initially recruited. The apparent diffusion coefficient, true diffusion coefficient (D), pseudodiffusion coefficient (D*), pseudodiffusion fraction (f), diffusion distribution coefficient, and diffusion heterogeneity index (Alpha) were measured by two independent radiologists. Spearman's correlation test was used to assess correlations between IVIM parameters and the regeneration index (RI), calculated as 100% × (the volume of the postoperative remnant liver - the volume of the preoperative remnant liver) / the volume of the preoperative remnant liver. Multivariate linear regression analyses were used to identify the factors for RI.

Finally, 54 HCC patients (45 men and 9 women, mean age 51.26 ± 10.41 years) were retrospectively analyzed. The intraclass correlation coefficient ranged from 0.842 to 0.918. In all patients, fibrosis stage was reclassified as F0-1 (n = 10), F2-3 (n = 26), and F4 (n = 18) using the METAVIR system. Spearman correlation test showed D* (r = 0.303, p = 0.026) was associated with RI; however, multivariate analysis showed that only D value was a significant predictor (p < 0.05) of RI. D and D*showed moderate correlations with fibrosis stage (r = -0.361, p = 0.007; r = -0.457, p = 0.001). Fibrosis stage showed a negative correlation with RI (r = -0.263, p = 0.015). In the 29 patients who underwent minor hepatectomy, only the D value showed a positive association (p < 0.05) with RI, and a negative correlation with fibrosis stage (r = -0.360, p = 0.018). However, in the 25 patients who underwent major hepatectomy, no IVIM parameters were associated with RI (p > 0.05).

The D and D* values, especially the D value, may be reliable preoperative predictors of liver regeneration.

• The D and D* values, especially the D value, derived from IVIM diffusion-weighted imaging may be useful markers for the preoperative prediction of liver regeneration in patients with HCC. • The D and D* values derived from IVIM diffusion-weighted imaging show significant negative correlations with fibrosis, an important predictor of liver regeneration. • No IVIM parameters were associated with liver regeneration in patients who underwent major hepatectomy, but the D value was a significant predictor of liver regeneration in patients who underwent minor hepatectomy.

Laparoscopic right hemihepatectomy (L-RHH) is still considered a technically complex procedure, which should only be performed by experienced surgeons in specialized centers. Future liver remnant modulation (FLRM) strategies, including portal vein embolization (PVE), and associating liver partition and portal vein ligation for staged hepatectomy (ALPPS), might increase the surgical difficulty of L-RHH, due to the distortion of hepatic anatomy, periportal inflammation, and fibrosis. Therefore, this study aims to evaluate the safety and feasibility of L-RHH after FLRM, when compared with ex novo L-RHH.

All consecutive right hemihepatectomies performed by a single surgeon in the period between October 2007 and March 2023 were retrospectively analyzed. The patient characteristics and perioperative outcomes of L-RHH after FLRM and ex novo L-RHH were compared.

A total of 59 patients were included in the analysis, of whom 33 underwent FLRM. Patients undergoing FLRM prior to L-RHH were most often male (93.9% vs. 42.3%, p < 0.001), had an ASA-score >2 (45.5% vs. 9.5%, p = 0.006), and underwent a two-stage hepatectomy (45.5% vs. 3.8% p < 0.001). L-RHH after FLRM was associated with longer operative time (median 360 vs. 300 min, p = 0.008) and Pringle duration (31 vs. 24 min, p = 0.011). Intraoperative blood loss, unfavorable intraoperative incidents, and conversion rates were similar in both groups. There were no significant differences in length of hospital stay and 30-day overall and severe morbidity rates. Radical resection margin (R0) and textbook outcome rates were equal. One patient who underwent an extended RHH in the FLRM group deceased within 90 days of surgery, due to post-hepatectomy liver failure.

L-RHH after FLRM is more technically complex than L-RHH ex novo, as objectified by longer operative time and Pringle duration. Nevertheless, this procedure appears safe and feasible in experienced hands.

Future liver remnant volume (FLRV), a risk factor for liver failure (PHLF) after major hepatectomy (MH), is not routinely measured. This study aimed to evaluate the association between FLRV and PHLF.

All patients undergoing MH (4 + segments) between 2011 and 2018 were identified from a prospectively maintained single-centre database. Perioperative data were collected for patients with PHLF, who were matched (1:2) with non-PHLF controls. FLRV and FLRV% (i.e., % of total liver volume) were calculated retrospectively from preoperative CT scans using Synapse-3D software, and compared between the PHLF and matched control groups.

Of 711 patients undergoing MH, PHLF occurred in 27 (3.8%), of whom 24 had preoperative CT scans available. These patients were matched to 48 non-PHLF controls, 98% of whom were classified as being at high risk of PHLF on preoperative risk scoring. FLRV% was significantly lower in the PHLF group, compared to matched controls (median: 28.7 vs. 35.2%, p = 0.010), with FLRV% < 30% in 58% and 29% of patients, respectively. Assessment of the ability of FLRV% to differentiate between PHLF and matched controls returned an area under the ROC curve of 0.69, and an optimal cut-off value of FLRV% < 31.5%, which yielded 79% sensitivity and 67% specificity.

FLRV% is significantly predictive of PHLF after MH, with over half of patients with PHLF having FLRV% < 30%. In light of this, we propose that all patients should undergo risk stratification prior to MH, with the high risk patients additionally being assessed with CT volumetry.

The aim of this study was to verify the prognostic impact of the tumor exposure at the liver transection margin (LTM) in left-sided perihilar cholangiocarcinoma and the impact of middle hepatic vein (MHV) resection on this exposure.

In perihilar cholangiocarcinoma, tumors are unexpectedly exposed at the LTM during left hemihepatectomy (LH).

Patients who underwent LH for perihilar cholangiocarcinoma during 2002 to 2018 were retrospectively evaluated. LH was classified into conventional and extended types, which preserved and resected the MHVs, respectively. Positive LTM was defined as the involvement of invasive carcinoma at the liver transection plane and/or the adjacent Glissonean pedicle exposed. The clinicopathologic features and survival outcomes were compared between procedures.

Among 236 patients, conventional and extended LHs were performed in 198 and 38 patients, respectively. The LTM was positive in 31 (13%) patients, with an incidence of 14% versus 8% ( P = 0.432) and 24% versus 0% in advanced tumors ( P = 0.011). Tumor size ≥ 18 mm ( P = 0.041), portal vein invasion ( P = 0.009), and conventional LH ( P = 0.028) independently predicted positive LTM. In patients with negative LTM, the survival was comparable between the two groups: 60.4% versus 59.2% at 3 years ( P = 0.206), which surpassed 17.7% for those with positive LTM in the conventional group ( P < 0.001). Multivariable analysis demonstrated that LTM status was an independent prognostic factor ( P = 0.009) along with ductal margin status ( P = 0.030).

The LTM status is an important prognostic factor in perihilar cholangiocarcinoma. Extended LH reduced the risk of tumor exposure at the LTM with a subsequent improvement in the survival, particularly in advanced tumors.

Although Makuuchi's criteria are widely used to determine the cut-off for safe liver resection, there have been few reports of concrete data supporting their validity. Here, we verified the utility of Makuuchi's criteria by comparing the operative mortality rates associated with liver resection between hepatocellular carcinoma (HCC) patients meeting or exceeding the criteria.

A database was built using data from 15 597 patients treated between 2000 and 2007 for whom values for all three variables included in Makuuchi's criteria for liver resection (clinical ascites, serum bilirubin, and indocyanine green clearance) were available. The patients were divided into those fulfilling (n = 12 175) or exceeding (n = 3422) the criteria. The postoperative mortality (death for any reason within 30 days) and long-term survival were compared between the two groups.

The operative mortality rate was significantly lower in patients meeting the criteria than in those exceeding the criteria (1.07% vs. 2.01%, respectively; p < 0.001). On multivariate analysis, exceeded the criteria was significantly associated with the risk for operative mortality (relative risk 2.08; 95% confidence interval (CI), 1.23-3.52; p = 0.007). Surgical indication meeting or exceeding the criteria was an independent factor for overall survival (hazard ratio 1.27; 95% CI, 1.18-1.36; p < 0.001).

Makuuchi's criteria are suitable for determining the indication for resection of HCC due to the reduction in risk of operative mortality.

Extended right lobectomy (ERL) for living donor liver transplant (LDLT) is selectively performed in many transplant centers and has shown excellent recipient outcomes as reported in previous studies. Yet, there is no universally accepted indication for ERL in respect to donor safety. Current study was designed to stratify risk factors of adverse donor outcome after ERL. A total of 79 living donors who underwent ERL for LDLT were included in analysis. Donors were classified as safety and hazard donor groups according to postoperative findings relevant to posthepatectomy liver failure classification by the International Study Group for Liver Surgery. On multivariable analysis, left lateral section volume <20% of total liver volume and nonpreservation of segment 4a venous drainage were the independent risk factors impairing postoperative outcomes. Despite the short-term impairment of liver function in hazard donor groups, all donors recovered and showed satisfactory remnant liver regeneration. However, these findings have implications in establishing selection criteria of donors eligible for ERL donation. In conclusion, LDLT using ERL graft can be safely performed provided so that left lateral section volume/total donor liver is ≥20% besides conventional donor selection criteria. Also, efforts to preserve segment 4a vein must be made in performing ERL graft procurement in LDLT donors.

For patients with hepatocellular carcinoma (HCC) undergoing hepatectomy, insufficient remnant liver regenerative capacity can lead to liver failure. The aim of this study was to evaluate the potential role of magnetic resonance elastography (MRE) for the preoperative prediction of liver regeneration in patients with HCC after partial hepatectomy (PH).

A total of 54 patients with HCC undergoing MRE prior to PH were retrospectively included. The total functional liver, volume of preoperative future liver remnant (LVpre), and volume of postoperative liver remnant (LVpost), respectively, were measured, and the regeneration index (RI) and parenchymal hepatic resection rate (PHRR) were manually calculated. Univariate and multivariate logistic regression analyses were conducted to identify factors associated with a high RI, and receiver operating characteristic (ROC) curves were employed to evaluate the diagnostic performance of the liver stiffness (LS) values. Patients were classified into three subgroups based on the value of PHRR: low PHRR (<30%), intermediate PHRR (30-50%), and high PHRR (>50%). Subsequently, Spearman correlation analysis was used to investigate the relationship between LS values and RI in the subgroups.

Multivariable analysis revealed a low LS value was associated with greater odds of a high RI [odds ratio (OR), 0.049; 95% confidence interval (CI): 0.002 to 0.980]. An optimal cutoff value of 3.30 kPa was used to divide all patients into a low RI group and a high RI group with an area under the curve (AUC) value of 0.882 (95% CI: 0.767 to 0.996). A significant negative relationship between RI and LS values (r=-0.799; P<0.001) was observed in the intermediate PHRR subgroup.

The LS values based on MRE may serve as a potential preoperative predictor of liver regeneration for patients with HCC undergoing PH.

Biliary drainage in patients managed palliatively for malignant hilar obstruction can be achieved by endoscopic transpapillary stenting using endoscopic retrograde cholangiography (ERC) or percutaneous transhepatic stent or catheter placement using percutaneous transhepatic cholangiography (PTC). This study compares ERC and PTC drainage for malignant hilar bile duct obstruction.

A retrospective study of drainage procedures at two academic hospitals was conducted from 2015 to 2020. Procedural success (divided into access-, bridging-, and technical success), therapeutic success, duration of therapeutic success and complications were analysed for different Bismuth-Corlette stricture types.

A total of 293 patients were included, 153 (52.2%) in the ERC group and 140 (47.8%) in the PTC group. Access and bridging success in the ERC and PTC groups were 83.5% vs. 97.2% (p < 0.001) and 90.2% vs. 84.5% (p = 0.119), respectively. Technical and therapeutic success were equivalent between the two groups (98.3% vs. 99.3%, p = 0.854 and 81.7% vs. 73.3%, p = 0.242). Duration of therapeutic success was longer after ERC drainage compared to PTC drainage (p = 0.009) with a 3-month gain in duration of therapeutic success after ERC drainage (p = 0.006, 95% CI [26-160]). Cholangitis rates were equivalent (21.4% vs. 24.7%, p = 0.530), pancreatitis was more common in the ERC group (9.4% vs. 0%, p < 0.001) and procedure-related deaths more common in the PTC group (6.0% vs. 15.8%, p < 0.001).

Although ERC and PTC drainage of malignant hilar obstruction were similar regarding technical and therapeutic success, ERC drainage was more durable. Outcome differences for B-C stricture types should be explored in future studies.

The knowledge accumulated throughout the years about liver regeneration has allowed a better understanding of normal liver physiology, by reconstructing the sequence of steps that this organ follows when it must rebuild itself after being injured. The scientific community has used several interdisciplinary approaches searching to improve liver regeneration and, therefore, human health. Here, we provide a brief history of the milestones that have advanced liver surgery, and review some of the new insights offered by the interdisciplinary work using animals, in vitro models, tissue engineering, or mathematical models to help advance the knowledge on liver regeneration. We also present several of the main approaches currently available aiming at providing liver support and overcoming organ shortage and we conclude with some of the challenges found in clinical practice and the ethical issues that have concomitantly emerged with the use of those approaches.

Portal vein embolization (PVE) is currently considered the standard of care to improve the volume of an inadequate future remnant liver (FRL) and decrease the risk of post-hepatectomy liver failure (PHLF). PHLF remains a significant limitation in performing major liver surgery and is the main cause of mortality after resection. The degree of hypertrophy obtained after PVE is variable and depends on multiple factors. Up to 20% of patients fail to undergo the planned surgery because of either an inadequate FRL growth or tumor progression after the PVE procedure (usually 6-8 wk are needed before surgery). The management of PVE failure is still debated, with a lack of consensus regarding the best clinical strategy. Different additional techniques have been proposed, such as sequential transarterial chemoembolization followed by PVE, segment 4 PVE, intra-portal administration of stem cells, dietary supplementation, and hepatic vein embolization. The aim of this review is to summarize the up-to-date strategies to overcome such difficult situations and discuss future perspectives on improving FRL hypertrophy.

Surgery is the cornerstone treatment for patients with primary or metastatic hepatic tumors. Thanks to surgical and anesthetic technological advances, current indications for liver resections have been significantly expanded to include any patient in whom all disease can be resected with a negative margin (R0) while preserving an adequate future residual liver (FRL). Posthepatectomy liver failure (PHLF) is still a feared complication following major liver surgery, associated with high morbidity, mortality and cost implications. PHLF is mainly linked to both the size and quality of the FRL. Significant advances have been made in detailed preoperative assessment to predict and mitigate this complication, even if an ideal methodology has yet to be defined. Several procedures have been described to induce hypertrophy of the FRL when needed. Each technique has its advantages and limitations, and among them portal vein embolization (PVE) is still considered the standard of care. About 20% of patients after PVE fail to undergo the scheduled hepatectomy, and newer secondary procedures, such as segment 4 embolization, ALPPS and HVE, have been proposed as salvage strategies. The aim of this review was to discuss the current modalities available and new perspectives in the optimization of FRL in patients undergoing major liver resection.

Liver transplantation has evolved into a safe life-saving operation and remains the golden standard in the treatment of end stage liver disease. The main limiting factor in the application of liver transplantation is graft shortage. Many strategies have been developed in order to alleviate graft shortage, such as living donor partial liver transplantation and split liver transplantation for adult and pediatric patients. In these strategies, liver volume assessment is of paramount importance, as size mismatch can have severe consequences in the success of liver transplantation.

To evaluate the safety, feasibility, and accuracy of light detection and ranging (LIDAR) 3D photography in the prediction of whole liver graft volume and mass.

Seven liver grafts procured for orthotopic liver transplantation from brain deceased donors were prospectively measured with an LIDAR handheld camera and their mass was calculated and compared to their actual weight.

The mean error of all measurements was 17.03 g (range 3.56-59.33 g). Statistical analysis of the data yielded a Pearson correlation coefficient index of 0.9968, indicating a strong correlation between the values and a Student's t-test P value of 0.26. Mean accuracy of the measurements was calculated at 97.88%.

Our preliminary data indicate that LIDAR scanning of liver grafts is a safe, cost-effective, and feasible method of ex vivo determination of whole liver volume and mass. More data are needed to determine the precision and accuracy of this method.

Inadequate volume of the future liver remnant (FLR) renders many patients with liver malignancies not amenable to surgical resection. Depending on the health of the liver and the patient in general, an FLR of 25-40% is required to avoid acute post-hepatectomy liver failure. Transarterial radioembolization (TARE) of a diseased liver lobe leads to atrophy of the embolized lobe and compensatory hypertrophy of the contralateral lobe. Although the absolute degree of FLR hypertrophy seems to be comparable to portal vein embolization, the kinetic of hypertrophy is much slower after radioembolization. However, TARE has the unique advantages of simultaneously offering local tumor control, possibly downstaging disease, and providing biological test of time. Progressions in technique and personalized dosimetry allow for more predictable ablative treatment of liver malignancies and preparation for major liver surgery. This article provides an overview of the existing literature, discusses the evidence, and considers possible criteria for patient selection.

Perihilar cholangiocarcinoma is a rare hepatobiliary malignancy that requires thoughtful, multidisciplinary evaluation in the preoperative setting to ensure optimal patient outcomes. Comprehensive preoperative imaging, including multiphase CT angiography and some form of cholangiographic assessment, is key to assessing resectability. While many staging systems exist, the Blumgart staging system provides the most useful combination of resectability assessment and prognostic information for use in the preoperative setting. Once resectability is confirmed, volumetric analysis should be performed. Upfront resection without biliary drainage or portal venous embolization may be considered in patients without cholangitis and an estimated functional liver remnant (FLR) > 40%. In patients with FLR < 40%, judicious use of biliary drainage is advised, with the goal of selective biliary drainage of the functional liver remnant. Percutaneous biliary drainage may avoid inadvertent contamination of the contralateral biliary tree and associated infectious complications, though the relative effectiveness of percutaneous and endoscopic techniques is an ongoing area of study and debate. Patients with low FLR also require intervention to induce hypertrophy, most commonly portal venous embolization, in an effort to reduce the rate of postoperative liver failure. Even with extensive preoperative workup, many patients will be found to have metastatic disease at exploration and diagnostic laparoscopy may reduce the rate of non-therapeutic laparotomy. Management of perihilar cholangiocarcinoma continues to evolve, with ongoing efforts to improve preoperative liver hypertrophy and to further define the role of transplantation in disease management.

Primary and secondary liver tumors are not always amenable to resection due to location and size. Inadequate future liver remnant (FLR) may prevent patients from having a curative resection or may result in increased postoperative morbidity and mortality from complications related to small-for-size syndrome (SFSS).

This comprehensive review analyzed the principles, mechanism and risk factors associated with SFSS and presented current available options in the evaluation of FLR when planning liver surgery. In addition, it provided a detailed description of specific modalities that can be used before, during or after surgery, in order to optimize the conditions for a safe resection and minimize the risk of SFSS.

Several methods which aim to reduce tumor burden, preserve healthy liver parenchyma, induce hypertrophy of FLR or prevent postoperative complications help minimize the risk of SFSS.

With those techniques the indications of radical treatment for patients with liver tumors have significantly expanded. The successful outcome depends on appropriate patient selection, the individualization and modification of interventions and the right timing of surgery.

Split-liver transplantation has allocation advantages over reduced-size transplantation because of its ability to benefit 2 recipients. However, prioritization of split-liver transplantation relies on the following 3 major assumptions that have never been tested in the United States: similar long-term transplant recipient outcomes, lower incidence of segment discard among split-liver procurements, and discard of segments among reduced-size procurements that would be otherwise "transplantable." We used United Network for Organ Sharing Standard Transplant Analysis and Research data to identify all split-liver (n = 1831) and reduced-size (n = 578) transplantation episodes in the United States between 2008 and 2018. Multivariable Cox proportional hazards modeling was used to compare 7-year all-cause graft loss between cohorts. Secondary analyses included etiology of 30-day all-cause graft loss events as well as the incidence and anatomy of discarded segments. We found no difference in 7-year all-cause graft loss (adjusted hazard ratio [aHR], 1.1; 95% confidence interval [CI], 0.8-1.5) or 30-day all-cause graft loss (aHR, 1.1; 95% CI, 0.7-1.8) between split-liver and reduced-size cohorts. Vascular thrombosis was the most common etiology of 30-day all-cause graft loss for both cohorts (56.4% versus 61.8% of 30-day graft losses; P = 0.85). Finally, reduced-size transplantation was associated with a significantly higher incidence of segment discard (50.0% versus 8.7%) that were overwhelmingly right-sided liver segments (93.6% versus 30.3%). Our results support the prioritization of split-liver over reduced-size transplantation whenever technically feasible.

The aim of the current study is to investigate the variations of anatomical (LVRem%) and functional remnant volumes (fLVRem%) and the dynamic uptake of Technetium-Mebrofinate (FRLF) measured from 99m Technetium-Mebrofinate SPECT-CT scan (TMSCT) in patients at high risk of post-hepatectomy liver failure (PHLF).

Variations in the measures of LVRem% and fLVRem% were assessed. The predictive accuracies of LVRem%, fLVRem% and FRLF with respect to PHLF were reported.

From the N = 92 scans performed, LVRem% and fLVRem% returned identical results in 15% of cases, and ±10 percentage points in 79% of cases. Some patients had larger discrepancies, with difference of >10 percentage points in 21% of cases. The difference was significant in those with primary liver cancers (-4.4 ± 9.2, p = 0.002). For the N = 29 patients that underwent surgery as planned on TMSCT, FRLF was a strong predictor of PHLF, with an AUROC of 0.83 (p = 0.005).

TMSCT is emerging as a useful modality in pre-operative assessment of patients undergoing major liver resection. For those with primary liver cancer, there is a significant variation in the anatomical and functional distributions that needs considered in surgical planning. Reduced FRLF, measured as the dynamic uptake in the future liver remnant, is a strong predictor of PHLF.

Assessment of the future liver remnant (FLR) is routinely performed before major hepatectomy. In R1-vascular one-stage hepatectomy (R1vasc-OSH), given the multiplanar dissection paths, the FLR is not easily predictable. Preoperative 3D-virtual casts may help. We evaluated the predictability of the FLR using the 3D-virtual cast in the R1vasc-OSH for multiple bilobar colorectal liver metastases (CLM).

Thirty consecutive patients with multiple bilobar CLMs scheduled for R1vasc-OSH were included. Predicted and real-FLRs were compared. Propensity score-matched analysis was used to determine the impact of 3D-virtual cast on postoperative complications.

Median number of CLM and resection areas were 12 (4-33) and 3 (1-8). Median predicted-FLR was 899 ml (558-1157) and 60% (42-85), while for the real-FLR 915 ml (566-1777) and 63% (43-87). Median discrepancy between predicted and real-FLR was -0.6% (p = 0.504), indicating a slight tendency to underestimate the FLR. The difference was more evident in more than 12 CLMs (p = 0.013). A discrepancy was not evident according to the number of resection areas (p = 0.316). No mortality occurred. Patients in virtual-group had lower major complications compared to nonvirtual-group (0% vs 18%, p-value 0.014).

FLR estimation based on 3D-analysis is feasible, provides a safe surgery and represents a promising method in planning R1vasc-OSH for patients with multiple bilobar CLMs.

Post-hepatectomy liver failure (PHLF) is a severe complication and main cause of death in patients undergoing hepatectomy. The aim of this study was to build a predictive model of PHLF in patients undergoing hepatectomy.

We retrospectively analyzed patients undergoing hepatectomy at Zhongshan Hospital, Fudan University from July 2015 to June 2018, and randomly divided them into development and internal validation cohorts. External validation was performed in an independent cohort. Least absolute shrinkage and selection operator (commonly referred to as LASSO) logistic regression was applied to identify predictors of PHLF, and multivariate binary logistic regression analysis was performed to establish the predictive model, which was visualized with a nomogram.

A total of 492 eligible patients were analyzed. LASSO and multivariate analysis identified three preoperative variables, total bilirubin (p=0.001), international normalized ratio (p<0.001) and platelet count (p=0.004), and two intraoperative variables, extent of resection (p=0.002) and blood loss (p=0.004), as independent predictors of PHLF. The area under receiver operating characteristic curve (referred to as AUROC) of the predictive model was 0.838 and outperformed the model for end-stage liver disease score, albumin-bilirubin score and platelet-albumin-bilirubin score (AUROCs: 0.723, 0.695 and 0.663, respectively; p<0.001 for all). The optimal cut-off value of the predictive model was 14.7. External validation showed the model could predict PHLF accurately and distinguish high-risk patients.

PHLF can be accurately predicted by this model in patients undergoing hepatectomy, which may significantly contribute to the postoperative care of these patients.