Current use of intraoperative ultrasound in modern liver surgery

Ultrasound plays an important role not only in preoperative diagnosis but also in intraoperative guidance for liver surgery.Intraoperative ultrasound(IOUS)has become an indispensable tool for modern liver surgeons,especially for minimally invasive surgeries,partially substituting for the surgeon’s hands.In fundamental mode,Doppler mode,contrast enhancement,elastography,and real-time virtual sonography,IOUS can provide additional real-time information regarding the intrahepatic anatomy,tumor site and characteristics,macrovascular invasion,resection margin,transection plane,perfusion and outflow of the remnant liver,and local ablation efficacy for both open and minimally invasive liver resections.Identification and localization of intrahepatic lesions and surrounding structures are crucial for performing liver resection,preserving the adjacent vital vascular and bile ducts,and sparing the functional liver parenchyma.Intraoperative ultrasound can provide critical information for intraoperative decision-making and navigation.Therefore,all liver surgeons must master IOUS techniques,and IOUS should be included in the training of modern liver surgeons.Further investigation of the potential benefits and advances in these techniques will increase the use of IOUS in modern liver surgeries worldwide.This study comprehensively reviews the current use of IOUS in modern liver surgeries.

Recurrence of cholestatic liver disease after living donor liver transplantation

End-stage liver disease, due to cholestatic liver diseases with an autoimmune background such as primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC), is considered a good indication for liver transplantation. Excellent overall patient and graft outcomes, based mostly on the experience from deceased donor liver transplantation (DDLT), have been reported. Due to the limited number of organ donations from deceased donors in most Asian countries, living donor liver transplantation (LDLT) is the mainstream treatment for end-stage liver disease, including that resulting from PBC and PSC. Although the initial experiences with LDLT for PBC and PSC seem satisfactory or comparable to that with DDLT, some aspects, including the timing of transplantation, the risk of recurrent disease, and its long-term clinical implications, require further evaluation. Whether or not the long-term outcomes of LDLT from a biologically related donor are equivalent to that of DDLT requiresfurther observations. The clinical course following LDLT may be affected by the genetic background shared between the recipient and the living related donor.

Surgical strategy for bile duct cancer:Advances and current limitations

The aim of this review is to describe recent advances and topics in the surgical management of bile duct cancer.Radical resection with a microscopically negative margin(R0)is the only way to cure cholangiocarcinoma and is associated with marked survival advantages compared to margin-positive resections.Complete resection of the tumor is the surgeon’s ultimate aim,and several advances in the surgical treatment for bile duct cancer have been made within the last two decades.Multidetector row computed tomography has emerged as an indispensable diagnostic modality for the precise preoperative evaluation of bile duct cancer,in terms of both longitudinal and vertical tumor invasion.Many meticulous operative procedures have been established,especially extended hepatectomy for hilar cholangiocarcinoma,to achieve a negative resection margin,which is the only prognostic factor under the control of the surgeon.A complete caudate lobectomy and resection of the inferior part of Couinaud’s segmentⅣcoupled with right or left hemihepatectomy has become the standard surgical procedure for hilar cholangiocarcinoma,and pyloruspreserving pancreaticoduodenectomy is the first choice for distal bile duct cancer.Limited resection for middle bile duct cancer is indicated for only strictly selected cases.Preoperative treatments including biliary drainage and portal vein embolization are also indicated for only selected patients,especially jaundiced patients anticipating major hepatectomy.Liver transplantation seems ideal for complete resection of bile duct cancer,but the high recurrence rate and decreased patient survival after liver transplant preclude it from being considered standard treatment.Adjuvant chemotherapy and radiotherapy have a potentially crucial role in prolonging survival and controlling local recurrence,but no definite regimen has been established to date.Further evidence is needed to fully define the role of liver transplantation and adjuvant chemo-radiotherapy.

Living-donor vs deceased-donor liver transplantation for patients with hepatocellular carcinoma

With the increasing prevalence of living-donor liver transplantation(LDLT) for patients with hepatocellular carcinoma(HCC),some authors have reported a potential increase in the HCC recurrence rates among LDLT recipients compared to deceased-donor liver transplantation(DDLT) recipients.The aim of this review is to encompass current opinions and clinical reports regarding differences in the outcome,especially the recurrence of HCC,between LDLT and DDLT.While some studies report impaired recurrence- free survival and increased recurrence rates among LDLT recipients,others,including large database studies,report comparable recurrence- free survival and recurrence rates between LDLT and DDLT.Studies supporting the increased recurrence in LDLT have linked graft regeneration to tumor progression,but we found no association between graft regeneration/initial graft volume and tumor recurrence among our 125 consecutive LDLTs for HCC cases.In the absence of a prospective study regarding the use of LDLT vs DDLT for HCC patients,there is no evidence to support the higher HCC recurrence after LDLT than DDLT,and LDLT remains a reasonable treatment option for HCC patients with cirrhosis.

Index of convexity:A novel liver function index using Tc-GSA scintigraphy

AIM:To investigate the clinical usefulness of a newly developed index,the "index of convexity(IOC)",for evaluating liver functional reserve using technetium99m-diethylenetriaminepentaacetic acid-galactosylhuman serum albumin(Tc-GSA scintigraphy).METHODS:In total,349 patients underwent Tc-GSA scintigraphy.Dynamic planner images were obtained,and time activity curves of the liver and heart were generated and analyzed.Our focus was on the convex shape of the liver accumulation curve.We developed a method for evaluating the extent of convexity and calculated an index that we named the IOC.Clearance index and receptor index were also calculated.The correlations between each GSA index with other liver function tests and liver histopathology were evaluated.RESULTS:Among the 3 indices generated by TcGSA,the IOC had the highest correlation with all other liver function tests(indocyanine green R15,albumin,prothrombin time,cholinesterase level,platelet count,and total bilirubin level).IOC can also differentiate between normal liver,chronic hepatitis,and liver cirrhosis with highest F ratio among GSA indices as determined by one-way analysis of variance.Receiver operating characteristic analysis demonstrated high diagnostic performance of IOC in the diagnosis of cirrhosis.CONCLUSION:IOC is a very simple and reliable index for assessing liver functional reserve,which may prove to be useful in combination with the indocyanine green test for preoperative assessment of hepatic resection.

Clostridium difficile-associated diarrhea after living donor liver transplantation

AIM： To assess the incidence and analyze the risk factors for Clostridium difficile-associated diarrhea （CDAD）after living donor liver transplantation （LDLT） in adult.METHODS： The micobiological data and medical records of 242 adult recipients that underwent LDLT at the Tokyo University Hospital were analyzed retrospectively. The independent risk factors for postoperative CDAD were identified.RESULTS： Postoperative CDAD occurred in 11 （5%）patients. Median onset of CDAD was postoperative d 19（range, 5-54）. In the multivariate analyses, male gender （odds ratio, 4.56） and serum creatinine （≥ 1.5 mg/dL,odds ratio, 16.0） independently predicted postoperative CDAD.CONCLUSION： CDAD should be considered in the differential diagnosis of patients with postoperative diarrhea after LDLT.

Living donor liver transplantation to patients with hepatitis C virus cirrhosis

Living donor liver transplantation （LDLT） is an alternative therapeutic option for patients with end-stage hepatitis C virus （HCV） cirrhosis because of the cadaveric organ shortage. HCV infection is now a leading indication for LDLT among adults worldwide, and there is a worse prognosis with HCV recurrence. The antivirus strategy after transplantation, however, is currently under debate. Recent updates on the clinical and therapeutic aspects of living donor liver transplantation for HCV are discussed in the present review.

Liver transplantation in HCV/HIV positive patients

Since the introduction of highly active antiretroviral therapy (HAART) in 1996 for human immunodeficiency virus (HIV)-infected patients, the incidence of liver diseases secondary to co-infection with hepatitis C has increased. Although data on the outcome of liver transplantation in HIV-infected recipients is limited, the overall results to date seem to be comparable to that in non-HIV-infected recipients. Liver transplant centers are now accepting HIV-infected individuals as organ recipients. Post-transplantation HIV replication is controlled by HAART. Hepatitis C re-infection of the liver graft, however, remains an important problem because cirrhotic changes of the liver graft may be more rapid in HIV-infected recipients. Interactions between the HAART components and immunosuppressive drugs influence drug metabolism and therefore meticulous monitoring of drug blood level concentrations is required. The risk of opportunistic infection in HIV-positive transplant patients seems to be similar to that in HIV-negative transplant recipients.