Extended 78% Hepatectomy in a Mouse Surgical Model.

Partial 2/3 hepatectomy in mice is used in research to study the liver's regenerative capacity and explore outcomes of liver resection in a number of disease models. In the classical partial 2/3 hepatectomy in mice, two of the five liver lobes, namely the left and median lobes representing approximately 66% of the liver mass, are resected en bloc with an expected postoperative survival of 100%. More aggressive partial hepatectomies are technically more challenging and hence, have seldom been used in mice. Our group has developed a mouse model of an extended hepatectomy technique in which three of the five liver lobes, including the left, median, and right upper lobes, are resected separately to remove approximately 78% of the total liver mass. This extended resection, in otherwise healthy mice, leaves a remnant liver that cannot always sustain adequate and timely regeneration. Failure to regenerate ultimately results in 50% postoperative lethality within 1 week due to fulminant hepatic failure. This procedure of extended 78% hepatectomy in mice represents a unique surgical model for the study of small-for-size syndrome and the evaluation of therapeutic strategies to improve liver regeneration and outcomes in the setting of liver transplantation or extended liver resection for cancer.

Partial liver resection alters the bile salt-FGF19 axis in patients with perihilar cholangiocarcinoma: Implications for liver regeneration.

BACKGROUND: Extended liver resection is the only treatment option for perihilar cholangiocarcinoma (pCCA). Bile salts and the gut hormone FGF19, both promoters of liver regeneration (LR), have not been investigated in patients undergoing resection for pCCA. We aimed to evaluate the bile salt-FGF19 axis perioperatively in pCCA and study its effects on LR. METHODS: Plasma bile salts, FGF19, and C4 (bile salt synthesis marker) were assessed in patients with pCCA and controls (colorectal liver metastases), before and after resection on postoperative days (PODs) 1, 3, and 7. Hepatic bile salts were determined in intraoperative liver biopsies. RESULTS: Partial liver resection in pCCA elicited a sharp decline in bile salt and FGF19 plasma levels on POD 1 and remained low thereafter, unlike in controls, where bile salts rose gradually. Preoperatively, suppressed C4 in pCCA normalized postoperatively to levels similar to those in the controls. The remnant liver volume and postoperative bilirubin levels were negatively associated with postoperative C4 levels. Furthermore, patients who developed postoperative liver failure had nearly undetectable C4 levels on POD 7. Hepatic bile salts strongly predicted hyperbilirubinemia on POD 7 in both groups. Finally, postoperative bile salt levels on day 7 were an independent predictor of LR. CONCLUSIONS: Partial liver resection alters the bile salt-FGF19 axis, but its derailment is unrelated to LR in pCCA. Postoperative monitoring of circulating bile salts and their production may be useful for monitoring LR.

Design of Path-Planning System for Interventional Thermal Ablation of Liver Tumors Based on CT Images.

OBJECTIVE: Aiming at the shortcomings of artificial surgical path planning for the thermal ablation of liver tumors, such as the time-consuming and labor-consuming process, and relying heavily on doctors' puncture experience, an automatic path-planning system for thermal ablation of liver tumors based on CT images is designed and implemented. METHODS: The system mainly includes three modules: image segmentation and three-dimensional reconstruction, automatic surgical path planning, and image information management. Through organ segmentation and three- dimensional reconstruction based on CT images, the personalized abdominal spatial anatomical structure of patients is obtained, which is convenient for surgical path planning. The weighted summation method based on clinical constraints and the concept of Pareto optimality are used to solve the multi-objective optimization problem, screen the optimal needle entry path, and realize the automatic planning of the thermal ablation path. The image information database was established to store the information related to the surgical path. RESULTS: In the discussion with clinicians, more than 78% of the paths generated by the planning system were considered to be effective, and the efficiency of system path planning is higher than doctors' planning efficiency. CONCLUSION: After improvement, the system can be used for the planning of the thermal ablation path of a liver tumor and has certain clinical application value.

Optical Sensing of Tissue Freezing Depth by Sapphire Cryo-Applicator and Steady-State Diffuse Reflectance Analysis.

This work describes a sapphire cryo-applicator with the ability to sense tissue freezing depth during cryosurgery by illumination of tissue and analyzing diffuse optical signals in a steady-state regime. The applicator was manufactured by the crystal growth technique and has several spatially resolved internal channels for accommodating optical fibers. The method of reconstructing freezing depth proposed in this work requires one illumination and two detection channels. The analysis of the detected intensities yields the estimation of the time evolution of the effective attenuation coefficient, which is compared with the theoretically calculated values obtained for a number of combinations of tissue parameters. The experimental test of the proposed applicator and approach for freezing depth reconstruction was performed using gelatin-based tissue phantom and rat liver tissue in vivo. It revealed the ability to estimate depth up to 8 mm. The in vivo study confirmed the feasibility of the applicator to sense the freezing depth of living tissues despite the possible diversity of their optical parameters. The results justify the potential of the described design of a sapphire instrument for cryosurgery.

[Videofluorescence navigation during parenchymal-sparing liver resections using a domestic fluorescence imaging system]. / Videofluorestsentnaya navigatsiya pri parenkhimosokhrannykh rezektsiyakh pecheni s ispol'zovaniem otechestvennoi sistemy fluorestsentnoi vizualizatsii.

Parenchyma- sparing liver resections are aimed at maximizing the possible preservation of parenchyma not affected by the tumor - a current trend in hepatopancreatobiliary surgery. On the other hand, a prerequisite for operations is to ensure their radicality. To effectively solve this problem, all diagnostic imaging methods available in the arsenal are used, which make it possible to comprehensively solve the issues of perioperative planning of the volume and technical features of the planned operation. Diagnostic imaging methods that allow intraoperative navigation through intraoperative, instrumentally based determination of the tumor border and resection plane have additional value. One of the methods of such mapping is ICG video fluorescence intraoperative navigation. An analysis of the clinical use of the domestic video fluorescent navigation system "MARS" for parenchymal-sparing resections of focal liver lesions is presented. An assessment was made of the dynamics of the distribution of the contrast agent during ICG videofluorescent mapping during parenchymal-sparing resection interventions on the liver, with the analysis of materials from histological examination of tissues taking into account three-zonal videofluorescent marking of the resection edge, performed using the domestic videofluorescence imaging system «MARS¼.

Effect of Dexmedetomidine Combined with Remifentanil on Emergence Agitation During Awakening from Sevoflurane Anesthesia for Pediatric Liver Surgery.

BACKGROUND We aimed to assess the effect of dexmedetomidine (Dex) combined with remifentanil on emergence agitation (EA) during awakening from sevoflurane anesthesia for pediatric liver surgery. MATERIAL AND METHODS Sixty children who underwent liver surgery in our hospital were prospectively selected and randomly allocated into group A (placebo+remifentanil+sevoflurane) or group B (Dex+remifentanil+sevoflurane). Mean arterial pressure (MAP) and heart rate (HR) at different time points, agitation score during awakening, behavioral status, pain level, and the incidence of postoperative adverse effects were compared in both groups. RESULTS Children in group B had lower HR and MAP levels immediately after tracheal extubation and 5 min after tracheal extubation than those in group A. The Aono's scores, PAED agitation scores, and CHIPP scores at 15 min and 30 min of admission to the PACU were lower in group B than in group A. The incidence of agitation during postoperative anesthesia awakening was lower in group B in contrast to group A. There was no significant difference in postoperative adverse reactions between group A and group B. CONCLUSIONS In pediatric liver surgery, the use of Dex+remifentanil+sevoflurane anesthesia can reduce the incidence of EA during the awakening period, stabilize hemodynamic levels, and relieve postoperative pain, and has fewer postoperative adverse effects, which warrants clinical application.

Long term impact of transjugular intrahepatic portosystemic shunt (TIPS) creation on hepatic morphology.

PURPOSE: The purpose of this study was to evaluate long-term morphologic changes occurring in the liver after TIPS creation with correlation with hepatic function to gain insight on the physiologic impact of TIPS on the liver. METHODS: This retrospective study included patients who underwent TIPS creation between 2005 and 2022 and had contrasted CT or MRI studies prior to and between 1 and 2 years post procedure. Strict exclusion criteria were applied to avoid confounding. Parenchymal volume and vessel measurements were assessed on the pre- and post-TIPS CT or MRI and MELD scores calculated. RESULTS: Of 580 patients undergoing TIPS creation, 65 patients (mean age, 55 years; 36 males) had pre-TIPS and post-TIPS imaging meeting inclusion criteria at median 16.5 months. After TIPS, the mean MELD score increased (12.9 to 15.4; p = 0.008) and total liver volume decreased (1730 to 1432 mL; p < 0.001). However, the magnitude of volume change did not correlate with MELD change. Neither portosystemic gradient nor TIPS laterality correlated with total or lobar hepatic volume changes or MELD changes. The main portal vein diameter increased (15.0 to 18.7 mm; p < 0.001). Thrombosis of the hepatic vein used for TIPS creation resulted in a mean increase in MELD of +4.1 compared to -2.1 in patients who had a patent and normal hepatic vein (p = 0.007). CONCLUSIONS: Given lack of correlation between portosystemic gradient, hepatic atrophy, hepatic function, and TIPS laterality, the alterations in portal flow dynamics after TIPS may not be impactful to hepatic function. However, hepatic vein patency after TIPS correlated with improved hepatic function.

Robotic sectionectomy versus robotic hemihepatectomy for anatomic liver resection: a comparative analysis of perioperative outcomes.

Sectionectomy is a parenchma-sparing alternative to (extended) right or left hemihepatectomy. However, the effectiveness and safety of robotic sectionectomy (RS) versus robotic (extended) hemihepatectomy (RH) for the treatment of liver tumors remains unclear. We reviewed our prospective database for consecutive patients who had undergone robotic hepatectomies between March 2021 and July 2023 and included all patients with RS and RH. Demographic data, perioperative outcomes and long-term outcomes were analyzed and compared between both groups. Thirty patients met our inclusion criteria, of whom 16 patients underwent RS as opposed to 14 patients who underwent RH. Baseline characteristics were comparable between the study groups. The duration of Pringle maneuver was significantly longer in the RS group, while the remaining operative details were comparable. There were no significant differences in posthepatectomy outcomes between the study groups. All patients had negative resection margins. RS is a safe and effective parenchyma-sparing treatment modality.

Full-left/Full-right Liver Splitting With Middle Hepatic Vein and Caval Partition During Dual Hypothermic Oxygenated Machine Perfusion.

BACKGROUND: Split liver transplantation is a valuable means of mitigating organ scarcity but requires significant surgical and logistical effort. Ex vivo splitting is associated with prolonged cold ischemia, with potentially negative effects on organ viability. Machine perfusion can mitigate the effects of ischemia-reperfusion injury by restoring cellular energy and improving outcomes. METHODS: We describe a novel technique of full-left/full-right liver splitting, with splitting and reconstruction of the vena cava and middle hepatic vein, with dual arterial and portal hypothermic oxygenated machine perfusion. The accompanying video depicts the main surgical passages, notably the splitting of the vena cava and middle hepatic vein, the parenchymal transection, and the venous reconstruction. RESULTS: The left graft was allocated to a pediatric patient having methylmalonic aciduria, whereas the right graft was allocated to an adult patient affected by hepatocellular carcinoma and cirrhosis. CONCLUSIONS: This technique allows ex situ splitting, counterbalancing prolonged ischemia with the positive effects of hypothermic oxygenated machine perfusion on graft viability. The venous outflow is preserved, safeguarding both grafts from venous congestion; all reconstructions can be performed ex situ, minimizing warm ischemia. Moreover, there is no need for highly skilled surgeons to reach the donor hospital, thereby simplifying logistical aspects.

Selective internal radiation therapy segmentectomy: A new minimally invasive curative option for primary liver malignancies?

Transarterial radioembolization or selective internal radiation therapy (SIRT) has emerged as a minimally invasive approach for the treatment of tumors. This percutaneous technique involves the local, intra-arterial delivery of radioactive microspheres directly into the tumor. Historically employed as a palliative measure for liver malignancies, SIRT has gained traction over the past decade as a potential curative option, mirroring the increasing role of radiation segmentectomy. The latest update of the BCLC hepatocellular carcinoma guidelines recognizes SIRT as an effective treatment modality comparable to other local ablative methods, particularly well-suited for patients where surgical resection or ablation is not feasible. Radiation segmentectomy is a more selective approach, aiming to deliver high-dose radiation to one to three specific hepatic segments, while minimizing damage to surrounding healthy tissue. Future research efforts in radiation segmentectomy should prioritize optimizing radiation dosimetry and refining the technique for super-selective administration of radiospheres within the designated hepatic segments.

Applying LASSO logistic regression for the prediction of biliary complications after ex vivo liver resection and autotransplantation in patients with end-stage hepatic alveolar echinococcosis.

BACKGROUND: The purpose of this study was to explore the relevant risk factors associated with biliary complications (BCs) in patients with end-stage hepatic alveolar echinococcosis (HAE) following ex vivo liver resection and autotransplantation (ELRA) and to establish and visualize a nomogram model. METHODS: This study retrospectively analysed patients with end-stage HAE who received ELRA treatment at the First Affiliated Hospital of Xinjiang Medical University between August 1, 2010 and May 10, 2023. The least absolute shrinkage and selection operator (LASSO) regression model was applied to optimize the feature variables for predicting the incidence of BCs following ELRA. Multivariate logistic regression analysis was used to develop a prognostic model by incorporating the selected feature variables from the LASSO regression model. The predictive ability, discrimination, consistency with the actual risk, and clinical utility of the candidate prediction model were evaluated using receiver operating characteristic (ROC) curves, calibration plots, and decision curve analysis (DCA). Internal validation was performed by the bootstrapping method. RESULTS: The candidate prediction nomogram included predictors such as age, hepatic bile duct dilation, portal hypertension, and regular resection based on hepatic segments. The model demonstrated good discrimination ability and a satisfactory calibration curve, with an area under the ROC curve (AUC) of 0.818 (95% CI 0.7417-0.8958). According to DCA, this prediction model can predict the risk of BCs occurrence within a probability threshold range of 9% to 85% to achieve clinical net benefit. CONCLUSIONS: A prognostic nomogram with good discriminative ability and high accuracy was developed and validated to predict BCs after ELRA in patients with end-stage HAE.

Feasibility and Safety of Percutaneous Puncture Guided by a 5G-Based Telerobotic Ultrasound System: An Experimental Study.

PURPOSE: To evaluate the feasibility and safety of percutaneous puncture guided by a 5th generation mobile communication technology (5G)-based telerobotic ultrasound system in phantom and animal experiments. MATERIALS AND METHODS: In the phantom experiment, 10 simulated lesions were punctured, once at each of two angles for each lesion, under the guidance of a telerobotic ultrasound system and ultrasound-guided freehand puncture. Student's t test was used to compare the two methods in terms of puncture accuracy, total operation duration, and puncture duration. In the animal experiment, under the guidance of the telerobotic ultrasound system, an 18G puncture needle was used to puncture 3 target steel beads in the liver, right kidney, and right gluteal muscle, respectively. The animal experiment had no freehand ultrasound-guided control group. After puncture, a CT scan was performed to verify the position of the puncture needle in relation to the target, and the complications and puncture duration, etc., were recorded. RESULTS: In the phantom experiment, the mean accuracies of puncture under telerobotic ultrasound guidance and conventional ultrasound guidance were 1.8 ± 0.3 mm and 1.6 ± 0.3 mm (P = 0.09), respectively; therefore, there was no significant difference in the accuracy of the two guide methods. In the animal experiment, the first-attempt puncture success (the needle tip close to the target) rate was 93%. Polypnea occurred during one puncture. No other intraoperative or postoperative complications were observed. CONCLUSION: Puncture guided by a 5G-based telerobotic ultrasound system has shown good feasibility and safety in phantom and animal experiments.

Advances in Tumor Management: Harnessing the Potential of Histotripsy.

Tissue ablation techniques have long been used in clinical settings to treat various oncologic diseases. However, many of these techniques are invasive and can cause substantial adverse effects. Histotripsy is a noninvasive, nonionizing, nonthermal tissue ablation technique that has the potential to replace surgical interventions in various clinical settings. Histotripsy works by delivering high-intensity focused ultrasound waves to target tissue. These waves create cavitation bubbles within tissues that rapidly expand and collapse, thereby mechanically fractionating the tissue into acellular debris that is subsequently absorbed by the body's immune system. Preclinical and clinical studies have demonstrated the efficacy of histotripsy in treating a range of diseases, including liver, pancreatic, renal, and prostate tumors. Safety outcomes of histotripsy have been generally favorable, with minimal adverse effects reported. However, further studies are needed to optimize the technique and understand its long-term effects. This review aims to discuss the importance of histotripsy as a noninvasive tissue ablation technique, the preclinical and clinical literature on histotripsy and its safety, and the potential applications of histotripsy in clinical practice. Keywords: Tumor Microenvironment, Ultrasound-High-Intensity Focused (HIFU), Ablation Techniques, Abdomen/GI, Genital/Reproductive, Nonthermal Tissue Ablation, Histotripsy, Clinical Trials, Preclinical Applications, Focused Ultrasound © RSNA, 2024.

Magnetic liver retraction in bariatric surgery: Is it possible?

One of the recent advances in bariatric surgery is the use of magnetic devices. This research paper describes magnetic liver retraction in morbidly obese patients during bariatric surgery. A descriptive, prospective and observational study was carried out, analyzing 100 patients in whom magnetic retraction was used. Mean and SD body mass index was 46.1 ± 5.09 kg/m2. The magnetic system was successfully used for liver retraction in 95% of cases; in only 5% of cases was its use not possible due to hepatomegaly and severe hepatic steatosis. According to the results, magnetic liver retraction can be safe and used in bariatric surgery, regardless of body mass index and with a low percentage of complications.

'Burn and Push' technique: A novel robotic liver parenchymal transection technique.

BACKGROUND: Liver parenchymal transection during robotic liver resection (RLR) remains a significant challenge due to the limited range of specialised instruments. This study introduces our 'Burn and Push' technique as a novel approach to address these challenges. METHODS: A retrospective analysis was conducted on 20 patients who underwent RLR using the 'Burn and Push' technique at Virginia Commonwealth University Health System from November 2021 to August 2023. The study evaluated peri- and post-operative outcomes. RESULTS: The median operation time was 241.5 min (range, 90-620 min), and the median blood loss was 100 mL (range, 10-600 mL). Major complications occurred in one case, with no instances of postoperative bleeding, bile leak, or liver failure. CONCLUSIONS: The 'Burn and Push' technique is a viable and efficient alternative for liver parenchymal transection in RLR. Further research with larger sample sizes and consideration of the learning curve is necessary to validate these findings.

The Effect of Pringle Maneuver Applied during Living Donor Hepatectomy on the Ischemia-Reperfusion Injury Observed in the Donors and Recipients.

Background and Objectives: The aim of this study is to evaluate the clinical and laboratory changes of ischemia and reperfusion injury in the remnant livers of donors with and without Pringle maneuver. Furthermore, we evaluated the recipients who have been transplanted with liver grafts from these donors. Methods and Materials: A total of 108 patients (54 living liver donors and 54 liver recipients) who underwent donor hepatectomy and recipients who living donor liver transplantation, were included in this randomized double-blind study between February 2021 and June 2021. The donors were divided into two groups: Pringle maneuver applied (n = 27) and Pringle maneuver not applied (n = 27). Similarly, recipients with implanted liver obtained from these donors were divided into two groups as the Pringle maneuver was performed (n = 27) and not performed (n = 27). Blood samples from donors and recipients were obtained on pre-operative, post-operative 0 h day (day of surgery), post-operative 1st day, post-operative 2nd day, post-operative 3rd day, post-operative 4th day, post-operative 5th day, and liver tissue was taken from the graft during the back table procedures. Liver function tests and complete blood count, coagulation tests, IL-1, IL-2, IL-6, TNF-α, and ß-galactosidase measurements, and histopathological findings were examined. Results: There was no statistically significant difference in the parameters of biochemical analyses for ischemia-reperfusion injury at all periods in the donors with and without the Pringle maneuver. Similarly, there was no statistically significant difference between in the recipients in who received liver grafts harvested with and without the Pringle maneuver. There was no statistically significant difference between the two recipient groups in terms of perioperative bleeding and early bile duct complications (p = 0.685). In the histopathological examinations, hepatocyte damage was significantly higher in the Pringle maneuver group (p = 0.001). Conclusions: Although the histological scoring of hepatocyte damage was found to be higher in the Pringle maneuver group, the Pringle maneuver did not augment ischemia-reperfusion injury in donors and recipients that was evaluated by clinical and laboratory analyses.

Evaluation and clinical significance of contrast-enhanced ultrasound on changes in liver blood flow perfusion after TIPS surgery.

To investigate the clinical value of contrast-enhanced ultrasound in the prediction of hepatic encephalopathy (HE) in patients with hepatitis B cirrhosis after intrahepatic portal-systemic shunt via jugular vein. In this retrospective study, we collected data from 75 patients with hepatitis B, cirrhosis, and portal hypertension who underwent jugular intrahepatic portosystemic shunt from February 2019 to February 2022. The diagnostic instrument used was the TOSHIBA Aplio500 color Doppler ultrasound with contrast-enhanced ultrasound capabilities. The trial group comprised 20 patients with HE within 3 months postsurgery, while the control group (CG) included 55 patients without HE within the same postoperative period. All patients underwent various examinations before and within 48 hours after surgery, including observation of liver and spleen size and stent position, as well as assessment of blood flow direction in portal and hepatic veins. Subsequently, contrast-enhanced ultrasound was employed to examine and observe perfusion changes of contrast agents in hepatic veins, hepatic arteries, and portal veins (PV). Changes in PV pressure gradient, intrahepatic, and stent blood flow perfusion (BFP) were explored in both postoperative trials and CGs. The trial group exhibited higher BFP volume, PV pressure gradient difference, and percentage decrease compared to the CG. A weak positive correlation was observed between blood flow within the liver stent and PV pressure gradient difference, as well as the percentage decrease in PV pressure gradient. The correlation coefficient between blood flowing perfusion volume within the stent and the difference in PV pressure gradient was R = 0.415 (P = .000). The correlating coefficient between BFP amount within the stent and the percentage decrease in PV pressure gradient was R = 0.261 (P = .027). The area under the receiver operating characteristic curve for stent perfusion volume, difference in PV pressure gradient, and percentage decrease in PV pressure gradient was 0.691, 0.759, and 0.742, respectively. An increase in PV pressure gradient accelerates blood flow within the stent, predisposing to HE. Changes in hepatic BFP following transjugular intrahepatic portosystemic shunt can effectively predict the occurrence of HE, demonstrating significant clinical relevance.