Systematic review and meta-analysis of the effect of N-acetylcysteine on outcomes after liver resection.

BACKGROUND: N-Acetylcysteine (NAC) is a recognized antioxidative agent that facilitates the conjugation of toxic metabolites. In recent years, NAC has been routinely used to limit ischaemia-reperfusion injury in liver transplantation. There remains, however, contradictory evidence on its effectiveness in liver resection. This meta-analysis examines the effectiveness of NAC in improving outcomes following hepatectomy. METHODS: A comprehensive search of the MEDLINE, EMBASE, and Cochrane databases was performed to identify relevant randomized controlled trials (RCTs) published since database inception until November 2023. The outcomes of Day 1 biochemical markers (lactate, ALT, bilirubin, and INR), length of stay, transfusion rates, and morbidity were extracted. Quantitative pooling of data was based on a random-effects model. The study protocol was registered on PROSPERO (Registration no: CRD42023442429). RESULTS: Five RCTs reporting on 388 patients undergoing hepatectomy were included in the analysis. There were no significant differences in patient demographics between groups. Post-operative lactate was lower in patients receiving NAC (WMD -0.61, 95% CI -1.19 to -0.04, I2 = 67%). There were, however, no differences in the post-operative INR (WMD -0.04, 95% CI -0.19 to 0.12, I2 = 96%) and ALT (WMD -94.94, 95% CI -228.46 to 40.38; I2 = 67%). More importantly, there were no statistically significant differences in length of stay, transfusion rates, and morbidity between the two groups. CONCLUSION: The administration of NAC in liver resection did not alter important biochemical parameters suggesting any real effectiveness in reducing hepatic dysfunction. There were no improvements in the clinical outcomes of length of stay, transfusion rates, and overall morbidity.

Efficacy of erector spinae plane block for postoperative analgesia after liver surgeries: a systematic review and meta-analysis.

BACKGROUND: Data on the effectiveness of erector spinae plane block (ESPB) for patients undergoing liver surgeries is limited and inconclusive. We hereby aimed to systematically review if ESPB can provide adequate analgesia after liver surgery. METHODS: PubMed, CENTRAL, Scopus, Embase, and gray literature were examined up to 25th April 2023 for randomized controlled trials (RCTs) comparing ESPB with control or spinal analgesia. RESULTS: Nine RCTs were included of which three compared ESPB with spinal analgesia. 24-hour opioid consumption did not differ significantly between ESPB vs. control (MD: -35.25 95% CI: -77.01, 6.52 I2 = 99%) or ESPB vs. spinal analgesia (MD: 2.32 95% CI: -6.12, 10.77 I2 = 91%). Comparing pain scores between ESPB and control, a small but significant effect favoring ESPB was noted at 12 h and 48 h, but not at 6-8 h and 24 h. Pain scores did not differ between ESPB and spinal analgesia. The risk of postoperative nausea and vomiting was also not significantly different between ESPB vs. control or spinal analgesia. GRADE assessment shows moderate certainty of evidence. CONCLUSION: ESPB may not provide any significant postoperative analgesia in liver surgery patients. There was a tendency of reduced opioid consumption with ESPB. Limited data also showed that ESPB and spinal analgesia had no difference in pain scores and 24-hour analgesic consumption.

The impact of 3D reconstruction technology on liver surgery in changing the pathway of surgical maneuvers: A case report.

INTRODUCTION: This case report illustrates the significant role that 3D technology can play in major hepatic surgery, aiding in the determination of the optimal surgical approach. CASE PRESENTATION: We present the case of a patient with metachronous liver metastasis from rectal cancer involving segments 6 and 7, extending to retroperitoneal structures such as the inferior vena cava (IVC) and the right renal vein (RRV). DISCUSSION: After confirming the feasibility of a right hepatectomy, we opted for a traditional posterior approach, avoiding the hanging maneuver. The 3D rendering was instrumental in this decision, revealing that the mass was in close proximity to the IVC at the 11 o'clock position, a critical area for surgical instruments during the hanging maneuver. CONCLUSION: When 2D imaging fails to provide sufficient information, 3D rendering can substantially aid the decision-making process.

Surgical risk stratification in patients with cirrhosis.

Individuals with cirrhosis experience higher morbidity and mortality rates than the general population, irrespective of the type or scope of surgery. This increased risk is attributed to adverse effects of liver disease, encompassing coagulation dysfunction, altered metabolism of anesthesia and sedatives, immunologic dysfunction, hemorrhage related to varices, malnutrition and frailty, impaired wound healing, as well as diminished portal blood flow, overall hepatic circulation, and hepatic oxygen supply during surgical procedures. Therefore, a frequent clinical dilemma is whether surgical interventions should be pursued in patients with cirrhosis. Several risk scores are widely used to aid in the decision-making process, each with specific advantages and limitations. This review aims to discuss the preoperative risk factors in patients with cirrhosis, describe and compare surgical risk assessment models used in everyday practice, provide insights into the surgical risk according to the type of surgery and present recommendations for optimizing those with cirrhosis for surgical procedures. As the primary focus is on currently available risk models, the review describes the predictive value of each model, highlighting its specific advantages and limitations. Furthermore, for models that do not account for the type of surgical procedure to be performed, the review suggests incorporating both patient-related and surgery-related risks into the decision-making process. Finally, we provide an algorithm for the preoperative assessment of patients with cirrhosis before elective surgery as well as guidance perioperative management.

Comparing a virtual reality head-mounted display to on-screen three-dimensional visualization and two-dimensional computed tomography data for training in decision making in hepatic surgery: a randomized controlled study.

OBJECTIVE: Evaluation of the benefits of a virtual reality (VR) environment with a head-mounted display (HMD) for decision-making in liver surgery. BACKGROUND: Training in liver surgery involves appraising radiologic images and considering the patient's clinical information. Accurate assessment of 2D-tomography images is complex and requires considerable experience, and often the images are divorced from the clinical information. We present a comprehensive and interactive tool for visualizing operation planning data in a VR environment using a head-mounted-display and compare it to 3D visualization and 2D-tomography. METHODS: Ninety medical students were randomized into three groups (1:1:1 ratio). All participants analyzed three liver surgery patient cases with increasing difficulty. The cases were analyzed using 2D-tomography data (group "2D"), a 3D visualization on a 2D display (group "3D") or within a VR environment (group "VR"). The VR environment was displayed using the "Oculus Rift ™" HMD technology. Participants answered 11 questions on anatomy, tumor involvement and surgical decision-making and 18 evaluative questions (Likert scale). RESULTS: Sum of correct answers were significantly higher in the 3D (7.1 ± 1.4, p < 0.001) and VR (7.1 ± 1.4, p < 0.001) groups than the 2D group (5.4 ± 1.4) while there was no difference between 3D and VR (p = 0.987). Times to answer in the 3D (6:44 ± 02:22 min, p < 0.001) and VR (6:24 ± 02:43 min, p < 0.001) groups were significantly faster than the 2D group (09:13 ± 03:10 min) while there was no difference between 3D and VR (p = 0.419). The VR environment was evaluated as most useful for identification of anatomic anomalies, risk and target structures and for the transfer of anatomical and pathological information to the intraoperative situation in the questionnaire. CONCLUSIONS: A VR environment with 3D visualization using a HMD is useful as a surgical training tool to accurately and quickly determine liver anatomy and tumor involvement in surgery.

Interleukin-8 is superior to CRP for the prediction of severe complications in a prospective cohort of patients undergoing major liver resection.

INTRODUCTION: Early detection of severe complications may reduce morbidity and mortality in patients undergoing hepatic resection. Therefore, we prospectively evaluated a panel of inflammatory blood markers for their value in predicting postoperative complications in patients undergoing liver surgery. METHODS: A total of 139 patients undergoing liver resections (45 wedge resections, 49 minor resections, and 45 major resections) were prospectively enrolled between August 2017 and December 2018. Leukocytes, CRP, neutrophil-lymphocyte ratio (NLR), thrombocyte-lymphocyte ratio (TLR), bilirubin, INR, and interleukin-6 and -8 (IL-6 and IL-8) were measured in blood drawn preoperatively and on postoperative days 1, 4, and 7. IL-6 and IL-8 were measured using standardized immunoassays approved for in vitro diagnostic use in Germany. ROC curve analysis was used to determine predictive values for the occurrence of severe postoperative complications (CDC ≥ 3). RESULTS: For wedge and minor resections, leukocyte counts at day 7 (AUC 0.80 and 0.82, respectively), IL-6 at day 7 (AUC 0.74 and 0.73, respectively), and CRP change (∆CRP) at day 7 (AUC 0.72 and 0.71, respectively) were significant predictors of severe postoperative complications. IL-8 failed in patients undergoing wedge resections, but was a significant predictor of severe complications after minor resections on day 7 (AUC 0.79), had the best predictive value in all patients on days 1, 4, and 7 (AUC 0.72, 0.72, and 0.80, respectively), and was the only marker with a significant predictive value in patients undergoing major liver resections (AUC on day 1: 0.70, day 4: 0.86, and day 7: 0.92). No other marker, especially not CRP, was predictive of severe complications after major liver surgery. CONCLUSION: IL-8 is superior to CRP in predicting severe complications in patients undergoing major hepatic resection and should be evaluated as a biomarker for patients undergoing major liver surgery. This is the first paper demonstrating a feasible implementation of IL-8 analysis in a clinical setting.

Recurrencia en echinococcosis quística hepática

El tratamiento quirúrgico de la equinococosis quística hepática se asocia (entre otras), con una tasa de recurrencia actual de hasta 27%, aunque es infrecuente la recurrencia después de la exéresis total de un quiste intacto. Por lo general, la recurrencia ocurre producto del derrame de estructuras parasitarias vivas a alguna cavidad, o de dejar residuos de germinal, vesículas hijas o protoescólices durante la cirugía. La recurrencia suele ser asintomática, por lo que el diagnóstico depende, casi exclusivamente, de un seguimiento riguroso y prolongado en el tiempo, con controles clínicos, determinaciones serológicas, e imágenes. El tratamiento puede incluir el uso de albendazol, asociado a técnicas de radiología intervencionista o cirugía. El objetivo de este manuscrito fue generar un documento de lectura referente a la recurrencia de la equinococosis quística hepática.

Surgical treatment of hepatic cystic echinococcosis is associated (among others), with a current recurrence rate of up to 27%; although recurrence after total resection of an intact cyst is rare. In general, recurrence occurs as a result of the spillage of living parasitic structures into a cavity, or of leaving germinal residues, daughter vesicles, or protoscolices during surgery. Recurrence is usually asymptomatic, so the diagnosis depends almost exclusively on a rigorous and prolonged follow-up, with clinical controls, serological determinations, and images. Treatment may include the use of albendazole, followed by interventional radiology techniques or surgery. The aim of this manuscript was to generate a reading document regarding the recurrence of hepatic cystic echinococcosis.

A narrative review of intrahepatic cholangiocarcinoma: a surgical curative option.

BACKGROUND AND OBJECTIVE: Cholangiocarcinoma (CCA) is the second commonest primary liver malignancy. Nowadays, the only available treatment with curative intent of intrahepatic cholangiocarcinoma (iCCA) is surgical resection, with a 5-year overall survival (OS) of 25-40%. However, recurrence rate remains high. In this comprehensive review, we describe the newest surgical strategies for iCCA management, including vascular resection, the role of mini-invasive surgery, liver transplant, strategies for future liver remnant augmentation, and the role of neoadjuvant therapies. METHODS: A review of medical databases (PubMed, Scopus and Cochrane Database) was conducted selecting most relevant articles in English language without a specific timeframe. KEY CONTENT AND FINDINGS: Multifocal presentation, vascular, perineural invasion, and lymph nodes involvement are associated with poor outcome. Prognostic factors are being investigated to improve therapeutic approach and outcomes. The role of lymph nodes dissection remains debated. Harvesting at least 6 lymph nodes is recommended to ensure accurate nodal staging. Liver transplantation (LT) recently represented a treatment option only in patients with unresectable early disease (≤2 cm). CONCLUSIONS: Surgical resection remains the only potentially curative treatment for patients with CCA, but continue understanding in diagnosis, operative technique and chemotherapies are changing the landscape in the prognosis. Multicentric and randomized studies are necessaries in the future research with the intent to personalize the treatments, improve patient selection for the resection and reduce recurrence rate.

Total portal vein replacement with peritoneal interposition graft during Whipple's procedure for extrahepatic cholangiocarcinoma: a technical report.

BACKGROUND: Aggressive surgical resection in locally advanced hepatopancreatobiliary (HPB) malignancies is frequently advocated as the only potentially curative treatment. In recent years, advances in chemotherapy regimens and surgical techniques have led to improved oncologic outcomes and overall survival, by increasing the rates of radical (R0) resections. Vascular resections are increasingly reported to further increase disease clearance rates. Within this perspective, the issue of vascular reconstruction has raised growing interest, drawing particular attention to vascular substitutes and surgical techniques for reconstruction. CASE PRESENTATION: A case of extrahepatic cholangiocarcinoma with high clinical suspicion of vascular infiltration of the portal trunk at preoperative assessment is reported. An autologous interposition graft, harvested from diaphragmatic peritoneum, was chosen as a vascular substitute leading to successful portal trunk reconstruction and overcoming all possible drawbacks associated with cadaveric and artificial grafts reconstructions. CONCLUSION: This solution was strategic to ensure complete oncologic clearance averting the risk of positive margins (R1) at final pathology.

Laparoscopic Microwave Ablation: Which Technologies Improve the Results.

Liver resection is the best treatment for hepatocellular carcinoma (HCC) when resectable. Unfortunately, many patients with HCC cannot undergo liver resection. Percutaneous thermoablation represents a valid alternative for inoperable neoplasms and for small HCCs, but it is not always possible to accomplish it. In cases where the percutaneous approach is not feasible (not a visible lesion or in hazardous locations), laparoscopic thermoablation may be indicated. HCC diagnosis is commonly obtained from imaging modalities, such as CT and MRI, However, the interpretation of radiological images, which have a two-dimensional appearance, during the surgical procedure and in particular during laparoscopy, can be very difficult in many cases for the surgeon who has to treat the tumor in a three-dimensional environment. In recent years, more technologies have helped surgeons to improve the results after ablative treatments. The three-dimensional reconstruction of the radiological images has allowed the surgeon to assess the exact position of the tumor both before the surgery (virtual reality) and during the surgery with immersive techniques (augmented reality). Furthermore, indocyanine green (ICG) fluorescence imaging seems to be a valid tool to enhance the precision of laparoscopic thermoablation. Finally, the association with laparoscopic ultrasound with contrast media could improve the localization and characteristics of tumor lesions. This article describes the use of hepatic three-dimensional modeling, ICG fluorescence imaging and laparoscopic ultrasound examination, convenient for improving the preoperative surgical preparation for personalized laparoscopic approach.

Does COVID-19 infection significantly affect liver transplantation? Results of liver transplantation in the COVID-19 era at a single, high-volume centre.

BACKGROUND: Liver transplantation is a proven management method for end-stage cirrhosis and is estimated to have increased life expectancy by 15 years. The COVID-19 pandemic posed a challenge to patients who were candid for a solid-organ transplant. It has been suggested that the outcomes of liver transplants could be adversely affected by the infection, as immunosuppression makes liver transplant candidates more susceptible to adverse effects while predisposing them to higher thrombotic events. MATERIAL AND METHODS: In this retrospective study, the cases who received liver transplants from January 2018 to March 2022 were assessed regarding early postoperative mortality rate and hepatic artery thrombosis (HAT) with COVID-19 infection. This study included 614 cases, of which 48 patients were infected. RESULTS: This study shows that the early COVID-19-related early postoperative mortality rates substantially increased in the elective setting (OR: 2.697), but the results for the acute liver failure were insignificant. The average model for end-stage liver disease score increased significantly during the pandemic due to new regulations. Although mortality rates increased during the pandemic, the data for the vaccination period show that mortality rates have equalised with the prepandemic era. Meanwhile, COVID-19 infection is assumed to have increased HAT by 1.6 times in the elective setting. CONCLUSION: This study shows that COVID-19 infection in an acute liver failure poses comparatively little risk; hence transplantation should be considered in such cases. Meanwhile, the hypercoagulative state induced by the infection predisposes this group of patients to higher HAT rates.

Augmented reality in liver surgery.

INTRODUCTION: During an operation, augmented reality (AR) enables surgeons to enrich their vision of the operating field by means of digital imagery, particularly as regards tumors and anatomical structures. While in some specialties, this type of technology is routinely ustilized, in liver surgery due to the complexity of modeling organ deformities in real time, its applications remain limited. At present, numerous teams are attempting to find a solution applicable to current practice, the objective being to overcome difficulties of intraoperative navigation in an opaque organ. OBJECTIVE: To identify, itemize and analyze series reporting AR techniques tested in liver surgery, the objectives being to establish a state of the art and to provide indications of perspectives for the future. METHODS: In compliance with the PRISMA guidelines and availing ourselves of the PubMed, Embase and Cochrane databases, we identified English-language articles published between January 2020 and January 2022 corresponding to the following keywords: augmented reality, hepatic surgery, liver and hepatectomy. RESULTS: Initially, 102 titles, studies and summaries were preselected. Twenty-eight corresponding to the inclusion criteria were included, reporting on 183patients operated with the help of AR by laparotomy (n=31) or laparoscopy (n=152). Several techniques of acquisition and visualization were reported. Anatomical precision was the main assessment criterion in 19 articles, with values ranging from 3mm to 14mm, followed by time of acquisition and clinical feasibility. CONCLUSION: While several AR technologies are presently being developed, due to insufficient anatomical precision their clinical applications have remained limited. That much said, numerous teams are currently working toward their optimization, and it is highly likely that in the short term, the application of AR in liver surgery will have become more frequent and effective. As for its clinical impact, notably in oncology, it remains to be assessed.

Cirrhosis and non-hepatic surgery in 2023 - a precision medicine approach.

INTRODUCTION: Patients with liver disease and portal hypertension frequently require surgery carrying high morbidity and mortality. Accurately estimating surgical risk remains challenging despite improved medical and surgical management. AREAS COVERED: This review aims to outline a comprehensive approach to preoperative assessment, appraise methods used to predict surgical risk, and provide an up-to-date overview of outcomes for patients with cirrhosis undergoing non-hepatic surgery. EXPERT OPINION: Robust preoperative, individually tailored, and precise risk assessment can reduce peri- and postoperative complications in patients with cirrhosis. Established prognostic scores aid stratification, providing an estimation of postoperative mortality, albeit with limitations. VOCAL-Penn Risk Score may provide greater precision than established liver severity scores. Amelioration of portal hypertension in advance of surgery may be considered, with prospective data demonstrating hepatic venous pressure gradient as a promising surrogate marker of postoperative outcomes. Morbidity and mortality vary between types of surgery with further studies required in patients with more advanced liver disease. Patient-specific considerations and practicing precision medicine may allow for improved postoperative outcomes.

Application of concept of enhanced recovery after surgery in the training of hepatic surgery specialists / 中华医学教育探索杂志

Objective:To investigate the application effect of the concept of enhanced recovery after surgery (ERAS) in the training of hepatic surgery specialists.Methods:Sixty attending physicians who had received 6 months of specialist training in the Hepatopancreatobiliary Surgery of the First Affiliated Hospital, School of Medicine, Zhejiang University, China in 2017-2019 were randomly divided into the control group and research group. The control group adopted the traditional training mode of hepatic surgery specialists, and the research group adopted the training mode of hepatic surgery specialists integrating the concept of ERAS. At the end of the training, the two groups were evaluated through theoretical examination and clinical practice. SPSS 25.0 was used for t test and Chi-square test. Results:The scores in theoretical knowledge [(91.70±2.87) vs. (89.60±2.88), P = 0.006], clinical thinking [(93.17±2.78) vs. (86.33±3.70), P < 0.001], and surgical simulation [(92.83±2.84) vs. (89.50±3.31), P = 0.013] were significantly better in the research group than in the control group. The questionnaire results showed that the satisfaction of specialists in the research group was better than that in the control group [(91.50±3.26) vs. (84.67±3.46), P < 0.001]. The results of clinical practice assessment showed that the patients managed by the specialist in the research group had faster postoperative recovery compared with the control group (length of stay: 6.10±1.80 vs. 9.90±1.60, P < 0.001). Conclusion:The training mode of hepatic surgery specialists integrating the concept of ERAS enables specialists to better master the theoretical knowledge and practical operation skills of hepatic surgery, and ultimately benefits patients.

Resección laparoscópica de tumor hepático / Laparoscopic Resection of Hepatic Tumor

Introducción: La cirugía laparoscópica desde su introducción en 1987 ha experimentado un enorme desarrollo. La cirugía hepática laparoscópica de los tumores hepáticos plantea diversas controversias: los cirujanos deben estar formados en cirugía hepática y cirugía laparoscópica, la técnica laparoscópica más adecuada no está bien definida (totalmente laparoscópica o asistida con la mano), el abordaje o disección de grandes vasos entraña riesgos importantes, los métodos de sección parenquimatosa están menos desarrollados que en la cirugía hepática abierta entre otros retos. A pesar de estos criterios existen situaciones en que la cirugía puede llevarse a cabo con seguridad, sobre todo en tumores benignos y malignos cuando las lesiones se localizan principalmente en segmentos anteriores del hígado. Objetivo: Presentar una paciente portadora de una lesión hepática intervenida quirúrgicamente por videolaparoscopía con buenos resultados y evolución excelente. Caso clínico: Paciente femenina de 42 años de edad; antecedentes de salud con presencia de dolor abdominal de tres meses de evolución en región de hipocondrio derecho y trastornos dispépticos esporádicos. Se confirmó imaginológicamente un tumor de 5 cm de diámetro en segmento III, de aspecto hemangiomatoso con componente mixto y sospecha de malignidad. Se realizó resección laparoscópica, el diagnóstico anatomopatológico fue nódulo regenerativo, tipo nódulo cirrótico con hemangioma cavernoso de localización periférica en hígado sano, sin evidencias de malignidad en los estudios realizados. Conclusiones: Las resecciones quirúrgicas de lesiones hepáticas abordables por vía laparoscópica son una opción terapéutica segura y muy válida en pacientes con indicaciones específicas(AU)

Introduction: Laparoscopic surgery, since its introduction in 1987, has undergone enormous development. Laparoscopic hepatic surgery of liver tumors raises several controversies: surgeons must be trained in hepatic surgery and laparoscopic surgery, the most appropriate laparoscopic technique is not well defined (totally laparoscopic or hand-assisted), the approach to or dissection of large vessels involves significant risks, the methods for parenchymal section are less developed than in open hepatic surgery, among other challenges. Despite these criterions, there are situations in which the surgery can be performed safely, above all in benign and malignant tumors when the lesions are located mainly in anterior segments of the liver. Objective: To present the case of a patient with a hepatic lesion and operated on by videolaparoscopy with good outcomes and excellent evolution. Clinical case: A 42-year-old female patient with a family history of disease presented abdominal pain of three months of evolution in the right hypochondrium and sporadic dyspeptic disorders. Imaging confirmed a tumor of 5 cm of diameter in segment III, with hemangiomatous aspect, mixed component and suspicion of malignancy. Laparoscopic resection was performed; the anatomopathological diagnosis was regenerative nodule, similar to a cirrhotic nodule with cavernous hemangioma of peripheral location in healthy liver, with no evidence of malignancy in the performed studies. Conclusions: Surgical resections of hepatic lesions that can be laparoscopically approached are a safe and very valid therapeutic option in patients with specific indications(AU)

Preliminary Studies on the Intrahepatic Anatomy of the Venous Vasculature in Cats.

Hepatic surgeries are often performed in cats to obtain a disease diagnosis, for the removal of masses, or for the treatment of shunts. Whereas the vascular anatomy of the liver has been studied in dogs, such evidence is lacking in cats. The current study used corrosion casts of portal and hepatic veins and computed tomography (CT) analysis of the casts to identify and describe the intrahepatic anatomy in healthy cat livers (n = 7). The results showed that feline livers had a consistent intrahepatic portal and venous anatomy, with only minor disparities in the numbers of secondary and tertiary branches. The feline portal vein consistently divided into two major branches and not three, as previously described in the literature for cats. The finding of a portal vein originating from the right medial lobe branch leading to the quadrate lobe in 4/7 specimens is a novelty of the feline anatomy that was not previously described in dogs. Partial to complete fusion of the caudate process of the caudate and the right lateral lobe, with a lack of clear venous separation between the lobes, was present in two specimens. These findings allowed a detailed description of the most common intrahepatic venous patterns in cats. Further anatomical studies should be encouraged to confirm the present findings and to investigate the utility of this information in surgical settings.

Synthesis and characterisation of a cancerous liver for presurgical planning and training applications.

OBJECTIVES: Oncology surgeons use animals and cadavers in training because of a lack of alternatives. The aim of this work was to develop a design methodology to create synthetic liver models familiar to surgeons, and to help plan, teach and rehearse patient-specific cancerous liver resection surgery. DESIGN: Synthetic gels were selected and processed to recreate accurate anthropomorphic qualities. Organic and synthetic materials were mechanically tested with the same equipment and standards to determine physical properties like hardness, elastic modulus and viscoelasticity. Collected data were compared with published data on the human liver. Patient-specific CT data were segmented and reconstructed and additive manufactured models were made of the liver vasculature, parenchyma and lesion. Using toolmaking and dissolvable scaffolds, models were transformed into tactile duplicates that could mimic liver tissue behaviour. RESULTS: Porcine liver tissue hardness was found to be 23 H00 (±0.1) and synthetic liver was 10 H00 (±2.3), while human parenchyma was reported as 15.06 H00 (±2.64). Average elastic Young's modulus of human liver was reported as 0.012 MPa, and synthetic liver was 0.012 MPa, but warmed porcine parenchyma was 0.28 MPa. The final liver model demonstrated a time-dependant viscoelastic response to cyclic loading. CONCLUSION: Synthetic liver was better than porcine liver at recreating the mechanical properties of living human liver. Warmed porcine liver was more brittle, less extensible and stiffer than both human and synthetic tissues. Qualitative surgical assessment of the model by a consultant liver surgeon showed vasculature was explorable and that bimanual palpation, organ delivery, transposition and organ slumping were analogous to human liver behaviour.

The Role of ICG in Robot-Assisted Liver Resections.

Introduction: Robotic-assisted liver surgery (RALS) with its known limitations is gaining more importance. The fluorescent dye, indocyanine green (ICG), is a way to overcome some of these limitations. It accumulates in or around hepatic masses. The integrated near-infrared cameras help to visualize this accumulation. We aimed to compare the influence of ICG staining on the surgical and oncological outcomes in patients undergoing RALS. Material and Methods: Patients who underwent RALS between 2014 and 2021 at the Department of General Surgery at the University Hospital Schleswig-Holstein, Campus Kiel, were included. In 2019, ICG-supported RALS was introduced. Results: Fifty-four patients were included, with twenty-eight patients (50.9%) receiving preoperative ICG. Hepatocellular carcinoma (32.1%) was the main entity resected, followed by the metastasis of colorectal cancers (17%) and focal nodular hyperplasia (15.1%). ICG staining worked for different tumor entities, but diffuse staining was noted in patients with liver cirrhosis. However, ICG-supported RALS lasted shorter (142.7 ± 61.8 min vs. 246.4 ± 98.6 min, p < 0.001), tumors resected in the ICG cohort were significantly smaller (27.1 ± 25.0 mm vs. 47.6 ± 35.2 mm, p = 0.021) and more R0 resections were achieved by ICG-supported RALS (96.3% vs. 80.8%, p = 0.075). Conclusions: ICG-supported RALS achieve surgically and oncologically safe results, while overcoming the limitations of RALS.

Nuevos avances en cirugía hepática: evaluación y planificación preoperatoria (Parte 1) / New advances in liver surgery: evaluation and preoperative planning

Resumen Los avances en la cirugía hepática de los últimos años han permitido resecciones hepáticas más extensa y complejas para el tratamiento de diferentes patologías del hígado sin un aumento excesivo de la morbimortalidad perioperatoria. El desarrollo de diferentes técnicas, tecnologías y herramientas para la evaluación preoperatoria han mejorado la planificación quirúrgica con el uso por ejemplo de las tecnologías audiovisuales e impresión de modelos en 3 dimensiones (3D) de alta fidelidad. Otros avances, han permitido realizar una mejor evaluación funcional del parénquima hepático y una caracterización más precisa de las lesiones con el uso por ejemplo de verde de indocianina, cintigrafía hepática y resonancia magnética con contraste hepatoespecífico. Este artículo describe algunos de los nuevos avances en la evaluación y planificación preoperatoria en cirugía hepática.

Advances in liver surgery in recent years have made it possible to achieve more extensive and complex liver resections for the treatment of different liver diseases without an excessive increase in perioperative morbidity and mortality. The development of different techniques, technologies and tools for preoperative evaluation have improved surgical planning with the use, for example, of audiovisual technologies and printing of high-fidelity 3-dimensional (3D) models. Other advances have allowed a better functional evaluation of the liver parenchyma and a more precise characterization of the lesions with the use, for example of indocyanine green or liver scintigraphy and magnetic resonance with hepatospecific contrast. This article describes some of the new advances in preoperative evaluation and planning in liver surgery.