Risk factors for biliary tract events during elective cholecystectomy waiting time after endoscopic retrograde cholangiopancreatography for choledocholithiasis.

Objectives: Endoscopic lithotripsy and elective cholecystectomy, followed by endoscopic retrograde cholangiopancreatography, are the first-line treatments for patients with common bile duct (CBD) stones (CBDS) and gallstones. However, this approach entails acute cholecystitis and recurrent cholangitis risk while patients await surgery. We aimed to identify acute cholecystitis and cholangitis risk factors during the waiting time for elective cholecystectomy. Methods: This study comprised 151 patients with CBDS combined with gallstones who underwent cholecystectomy within 90 days of the first endoscopic retrograde cholangiopancreatography at two tertiary care centers between January 2019 and October 2021. Results: The incidence of biliary tract events (acute cholecystitis, acute cholangitis, or any complications requiring unplanned cholangiopancreatography) was 28% (43 cases). In univariate and multivariate analyses, plastic stent placement as a bridge to surgery for the first treatment of CBDS was an independent risk factor for biliary tract events during the waiting time for surgery (odds ratio 4.25, p = 0.002). A subgroup analysis among those with plastic stent placement revealed a CBD diameter of ≤ 10 mm as an independent risk factor for acute cholecystitis (odds ratio 4.32; p = 0.027); a CBD diameter ≥ 11 mm was an independent risk factor for acute cholangitis and unplanned re-endoscopic retrograde cholangiopancreatography (odds ratio 5.66; p = 0.01). Conclusions: Plastic stent placement for CBDS before elective cholecystectomy increases the risk of acute cholecystitis or acute cholangitis during the waiting time for elective cholecystectomy.

Genetic alteration of SLCO1B3 defines constitutional indocyanine green excretory defect in patients who underwent hepatectomy.

AIM: Constitutional indocyanine green (ICG) excretory defects must be distinguished when assessing liver function. The absence of OATP1B3 expression due to homogenous alterations in the SLCO1B3 gene has been recently reported to induce ICG excretory defects; however, its association with the clinical examinations and the clinical implications of heterogeneous SLCO1B3 gene alteration remain unclear. METHODS: OATP1B3 expression was evaluated in 49 patients who underwent hepatectomy after evaluation of the ICG retention rate at 15 min (ICGR15) and technetium-99 m-galactosyl serum albumin (99mTc-GSA) hepatic scintigraphy. Additionally, alterations in SLCO1B3 were analyzed in patients without OATP1B3 expression. Subsequently, 59 patients who underwent hepatectomy for colorectal liver metastasis (CRLM) were analyzed. RESULTS: Of 49 patients, 6 (12%) had absent OATP1B3 expression. They had significantly higher ICGR15 value (74.7% vs. 23.5%; p < 0.0001), better modified albumin-bilirubin (ALBI) grade (≤grade 2A, 100% vs. 42%; p = 0.010), more normal 99mTc-GSA hepatic scintigraphy (100% vs. 28%; p = 0.0003), and better pathological liver fibrosis (F0-1, 100% vs. 49%; p = 0.027) compared to those with OATP1B3 expression. Three available frozen blocks of cases without OATP1B3 expression showed homozygous alterations in SLCO1B3. Of 59 patients with CRLM in normal liver background, five (8.5%) had heterozygous insertion in SLCO1B3, however they had no difference in ICGR15 values or other clinical findings compared to the other patients. CONCLUSIONS: Constitutional ICG excretory defects may be defined by the complete absence of OATP1B3 expression. The modified ALBI grade and 99mTc-GSA hepatic scintigraphy were useful for detecting constitutional ICG excretory defects.

Pancreaticoduodenectomy after postoperative gastric tube reconstruction for esophageal cancer with median arcuate ligament syndrome: a case report.

BACKGROUND: Pancreaticoduodenectomy (PD) is considered a challenging surgery for resecting the gastroduodenal artery (GDA), right gastric artery (RGA), and lymph node tumors. In cases of pancreatic head cancer surgery, vascular anastomosis or right gastroepiploic artery (RGEA)/GDA preservation is necessary after postoperative gastric tube reconstruction for esophageal cancer. Therefore, we report for the first time an extremely rare case of PD in a patient with pancreatic head cancer and median arcuate ligament syndrome (MALS) after gastric tube reconstruction following esophageal cancer surgery, in which the entire pancreatic head arcade was preserved. CASE PRESENTATION: The patient was a 76-year-old man who had undergone esophageal cancer surgery after sternal gastric tube reconstruction 7 years ago. He was referred to our hospital because of the suspicion of intraductal papillary mucinous carcinoma (IPMC) owing to an enlarged cystic lesion and a substantial component in the uncinate process of the pancreas. Preoperative three-dimensional computed (3D-CT) tomography angiography showed celiac axis stenosis and pancreatic head arcade dilation. The diagnosis was IPMC without evidence of invasion; therefore, gastric tube blood flow was maintained by preserving the GDA and RGEA. Due to MALS, the GDA blood flow was supplied through the pancreatic head arcade, necessitating its preservation. The GDA-RGEA, right gastroepiploic vein, and anterior superior pancreaticoduodenal artery were taped over the entire pancreatic head for preservation. The inferior pancreaticoduodenal artery (IPDA) was also taped on the dorsal pancreas and the posterior or anterior IPDA, which further bifurcates were taped to preserve them. Subsequently, PD was performed. CONCLUSION: We report a case of PD after gastric tube reconstruction for esophageal cancer with MALS, in which the pancreatic head arcade vessels were successfully preserved using 3D-CT to confirm the operation of the vessels.

Successful intrahepatic cholangiocarcinoma conversion surgery after administration of fibroblast growth factor receptor inhibitor.

We describe a case of a 47-year-old male patient with initially unresectable intrahepatic cholangiocarcinoma of the right liver lobe with tumor thrombi extending from the right bile duct to the common and left bile ducts. Conventional chemotherapy with gemcitabine and cisplatin for 19 months resulted in progressive disease. Subsequently, a comprehensive genome profile revealed fibroblast growth factor receptor 2 rearrangement, and hence, pemigatinib administration was initiated. After 6 months of pemigatinib therapy, significant shrinking of the tumor and disappearance of the tumor thrombi in the common and left bile duct were observed. Subsequently, the patient underwent conversion surgery, resulting in successful radical resection of the tumor. The patient has been disease-free for 7 months.

Clinical utility of the forward-viewing echoendoscope in patients after pancreatoduodenectomy: A prospective study.

Background and Objectives: Endoscopic treatment of obstructive jaundice and pancreatitis due to hepaticojejunostomy (H-J), pancreatojejunostomy (P-J) strictures, and tumor recurrence after pancreatoduodenectomy (PD) is technically challenging. Treatment of P-J strictures results in poor outcomes. Although conventional EUS that has an oblique view is not suitable for such patients, forward-viewing EUS (FV-EUS) may become a useful option. This study aimed to evaluate the feasibility and efficacy of FV-EUS in patients who have undergone PD. Methods: Patients with PD who were scheduled to undergo diagnosis and treatment using FV-EUS for H-J or P-J lesions were enrolled in this single-center prospective study. After observation of the P-J and H-J using FV-EUS according to a predetermined protocol, treatment using FV-EUS was performed as needed. Results: A total of 30 patients were enrolled, and FV-EUS was used to observe P-J and H-J in 24 and 28 patients, respectively. The detection rates of P-J and H-J by endoscopy were 50% (12/24) and 96.4% (27/28), respectively, and by EUS were 70.8% (17/24) and 100% (28/28), respectively. Of these, P-J and H-J were found by endoscopy only after EUS observation in 3 and 1 patient, respectively. The success rates of endoscopic treatment using FV-EUS were 66.7% (2/3), 95.2% (20/21), and 25% (1/4) for benign P-J strictures, benign H-J strictures, and tumor recurrence, respectively. Conclusions: Endoscopic treatment using FV-EUS is feasible and effective for patients after PD. Moreover, FV-EUS increases the P-J lesion detection rate by adding EUS observation.

[Gallbladder carcinosarcoma associated with pancreaticobiliary maljunction with biliary dilation:a case report].

A 68-year-old female patient was referred to our hospital with acute cholangitis. Computed tomography revealed common bile duct dilatation, gallbladder fundal tumor, and gallbladder wall thickening attached to the tumor. Cholangiography revealed pancreaticobiliary maljunction with biliary dilation. The patient was diagnosed with pancreaticobiliary maljunction with biliary dilation and gallbladder cancer and underwent liver S4b+5 and bile duct resection and reconstruction. Pathological results revealed that the gallbladder fundal tumor included sarcoma, and the gallbladder wall thickening had adenocarcinoma;thus, the patient was diagnosed with gallbladder carcinosarcoma.

Resection and reconstruction of the largest abdominal vein system (the inferior vena cava, hepatic, and portal vein): a narrative review.

Background and Objective: As tumors invade major abdominal veins, surgical procedures are transformed from simple and basic to complicated and challenging. In this narrative review, we focus on what is currently known and not known regarding the technical aspects of major abdominal venous resection and its reconstruction, patency, and oncologic benefit in a cross-cutting perspective. Methods: A systematic literature search was performed in PubMed and Semantic Scholar from inception up to October 18, 2023. We reviewed 106 papers by title, abstract, and full text regarding resection or reconstruction of the inferior vena cava, hepatic vein confluence, portal vein (PV), and middle hepatic vein (MHV) tributaries in living donor liver transplantation (LDLT) in a cross-cutting perspective. Key Content and Findings: The oncologic benefit of aggressive hepatic vein resection with suitable reconstruction against adenocarcinoma remains unclear, and further studies are required to clarify this point. A superior mesenteric/PV resection is now a universal, indispensable, and effective procedure for pancreatic ductal adenocarcinoma. Although many case series using tailor-made autologous venous grafts have been reported, not only size mismatch but also additional surgical incisions and a longer operation time remain obstacles for venous reconstruction. The use of autologous alternative tissue remains only an alternative procedure because the patency rate of customized tubular conduit type to interpose or replace the resected vein is not known. Unlike arterial replacement, venous replacement using synthetic vascular grafts is still rarely reported and there are several inherent limitations except for reconstruction of tributaries of MHV in LDLT. Conclusions: Various approaches to abdominal vein resection and replacement or reconstruction are technically feasible with satisfactory results. Synthetic vascular grafts may be appropriate but have a certain rate of complications.

Three-Dimensional Bio-Printed Tubular Tissue Using Dermal Fibroblast Cells as a New Tissue-Engineered Vascular Graft for Venous Replacement.

The current study was a preliminary evaluation of the feasibility and biologic features of three-dimensionally bio-printed tissue-engineered (3D bio-printed) vascular grafts comprising dermal fibroblast spheroids for venous replacement in rats and swine. The scaffold-free tubular tissue was made by the 3D bio-printer with normal human dermal fibroblasts. The tubular tissues were implanted into the infrarenal inferior vena cava of 4 male F344-rnu/rnu athymic nude rats and the short-term patency and histologic features were analyzed. A larger 3D bio-printed swine dermal fibroblast-derived prototype of tubular tissue was implanted into the right jugular vein of a swine and patency was evaluated at 4 weeks. The short-term patency rate was 100%. Immunohistochemistry analysis showed von Willebrand factor positivity on day 2, with more limited positivity observed on the luminal surface on day 5. Although the cross-sectional area of the wall differed significantly between preimplantation and days 2 and 5, suggesting swelling of the tubular tissue wall (both p < 0.01), the luminal diameter of the tubular tissues was not significantly altered during this period. The 3D bio-printed scaffold-free tubular tissues using human dermal or swine fibroblast spheroids may produce better tissue-engineered vascular grafts for venous replacement in rats or swine.

Endoscopic ultrasound-guided fine needle biopsy diagnosis of circumferentially extraluminal mucosa-associated lymphoid tissue lymphoma in the transverse colon: a case report.

A 61-year-old man present to us with continued abdominal pain without abdominal tenderness for 1 month. Blood testing showed elevated biliary enzymes and inflammation. Contrast-enhanced computed tomography (CT) revealed thickening of the transverse colon with relatively strong enhancement but no bile duct dilatation. Colonoscopy revealed localized edema and granular mucosa in the transverse colon. Fluoroscopic endoscopy exhibited the absence of haustra. Multiple biopsies were performed, but differentiation between mild inflammation and mucosa-associated lymphoid tissue (MALT) lymphoma was inconclusive. To establish a definitive diagnosis, transgastric endoscopic ultrasound-guided fine needle biopsy of the hypoechoic mass was performed. Histopathological analysis exhibited the proliferation of small-sized lymphocytes. Fluorescence in situ hybridization revealed the characteristic API2-MALT1 translocation of MALT lymphoma. We performed liver biopsy to investigate biliary enzyme elevation. Histopathology confirmed lymphocytic infiltration within Glisson's capsule. Immunohistochemistry showed positive for CD20 and negative for CD3 and CD5, signifying the infiltration of MALT lymphoma in the liver. Based on these findings, we diagnosed MALT lymphoma, Lugano classification Stage IV. We performed bendamustine-rituximab (BR)-combined therapy. After six courses of BR-combined therapy, colonoscopy revealed improvement in the lead pipe sign and CT revealed disappearance of the mass.

Efficacy of a Novel Tapered Contrast Catheter for Endoscopic Ultrasound-Guided Hepaticogastrostomy: A Multicenter Study.

Background: Endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) is an alternative for failed endoscopic retrograde cholangiopancreatography (ERCP), with current success rates of 65-84% considered suboptimal. A novel ERCP catheter (SHOREN, Kaneka Corporation, Osaka, Japan) with a tapered 3.3-French tip may facilitate smoother insertion, potentially improving outcomes. Methods: This retrospective analysis encompassed EUS-HGS procedures conducted from January 2021 to August 2023 at four institutions. The aim of this study was to compare the performance of conventional and novel ERCP contrast catheters regarding the success rate of single-attempt catheter insertion, failure rates, technical success rates, and incidence of adverse events. Results: The study included 48 patients; 26 underwent EUS-HGS using conventional catheters and 22 with the novel catheter. The novel catheter achieved higher success rates in single-attempt insertions (96.5% vs. 80.8%) and lower failure rates (4.6% vs. 7.7%). The occurrence of bile peritonitis was comparable between the two groups. Conclusions: The novel ERCP contrast catheter with a tapered tip appears to contribute to successful catheter insertion and is useful for EUS-HGS.

Thick silk fibroin vascular graft: A promising tissue-engineered scaffold material for abdominal vein grafts in middle-sized mammals.

Abdominal vein replacement with synthetic tissue-engineered vascular grafts constructed from silk-based scaffold material has not been reported in middle-sized mammals. Fourteen canines that underwent caudal vena cava replacement with a silk fibroin (SF) vascular graft (15 mm long and 8 mm diameter) prepared with natural silk biocompatible thread were allocated to two groups, thin and thick SF groups, based on the graft wall thickness. The short-term patency rate and histologic reactions were compared. The patency rate at 2 weeks after replacement in the thin and thick SF groups was 50% and 88%, respectively (p = 0.04). CD31-positive endothelial cells covered the luminal surface of both groups at 4 weeks. The elastic modulus of the thick SF graft was significantly better than that of the thin SF graft (0.0210 and 0.0007 N/m2, p < 0.01). Roundness of thick SF groups (o = 0.8 mm) was better than thin SF (o = 2.0 mm). There was significant difference between the groups (p = 0.01). SF vascular grafts are a promising tissue-engineered scaffold material for abdominal venous system replacement in middle-sized mammals, with thick-walled grafts being superior to thin-walled grafts.

Metallic Stents for Hepatic Venous Outflow Obstruction After Living-Donor Liver Transplantation and their Therapeutic Effects.

BACKGROUND: Living-donor liver transplantation (LDLT) is established as a standard therapy for end-stage liver disease; however, vessel reconstruction is more demanding due to the short length and small size of the available structures compared with deceased-donor whole liver transplantation. Interventional radiology (IR) has become the first-line treatment for vascular complications after LDLT. Hepatic venous outflow obstruction (HVOO) is a life-threatening complication after LDLT. The aim of this study of 592 adult-to-adult LDLT cases was to investigate the safety and efficacy of stent implantation for HVOO after LDLT. METHODS: Records of patients who developed HVOO requiring any treatment were collected with special reference to the metallic stent implantation. There were 232 left-side grafts and 360 right-side grafts. Sixteen cases developed HVOO after LDLT with an incidence rate of 2.7%, 5 with a left liver graft (2%), and 11 with a right-side graft (3%). The IR was attempted for 14 cases; among those, 8 cases were treated by stent implantation. RESULTS: The technical success rate of the initial stent implantation was 100%. The pressure gradient at the stenotic site significantly improved from 12.2 (range, 10.9-20.4 cm H2O) to 3.9 cm H2O (range, 1.4-8.2 cm H2O; P = .03). The volume of the congested graft liver decreased significantly from 1448 (range, 788-2170 mL) to 1265 mL (range, 748-1665 mL; P = .01), and the serum albumin level improved significantly from 3.3 (range, 1.7-3.7 g/dL) to 3.7 g/dL (range, 2.9-4.1 g/dL; P = .02). No procedure-related complication was noted, and the long-term stent patency was 100%. CONCLUSION: Metallic stent implantation for stenotic venous anastomosis after LDLT is a safe and effective treatment.

Incidental detection of upper gastrointestinal epithelial neoplasia by screening endoscopy prior to endoscopic ultrasonography in patients with pancreaticobiliary disease.

BACKGROUND: Screening esophagogastroduodenoscopy plays an important role in the early detection of upper gastrointestinal cancer. To provide more opportunities for patients with pancreaticobiliary disease to undergo this screening, we have performed esophagogastroduodenoscopy prior to endoscopic ultrasonography. However, the usefulness of this protocol is not elucidated. This study aimed to investigate the utility of screening esophagogastroduodenoscopy in this protocol in the detection of upper gastrointestinal epithelial neoplasms. METHODS: The outcomes of screening esophagogastroduodenoscopy performed prior to endoscopic ultrasonography in patients with pancreaticobiliary disease at our hospital between April 2020 and September 2022 were investigated. A logistic regression model was used to identify factors affecting the detection of epithelial neoplasms. Additionally, we compared the detection rate of gastric epithelial neoplasms between screening esophagogastroduodenoscopy performed prior to endoscopic ultrasonography and that performed at our medical checkup center. RESULTS: A total of 615 screening esophagogastroduodenoscopies prior to endoscopic ultrasonography were performed, and 12 (2.0%) epithelial neoplasms were detected, including esophageal lesions (n = 2) and gastric lesions (n = 10). Of these lesions, 75% (9/12) underwent curative endoscopic resection. A multivariate analysis showed that open-type gastric mucosal atrophy (odds ratio, 7.7; 95% confidence interval, 1.5-38.4; p = 0.01) and the use of magnification endoscopy (odds ratio, 7.3; 95% confidence interval, 1.9-27.9; p < 0.01) independently affected the detection of epithelial neoplasms. The detection rate of gastric epithelial neoplasms was significantly higher using this protocol than that in our medical checkup center (1.6% versus 0.2%, p < 0.01). CONCLUSIONS: A protocol of screening esophagogastroduodenoscopy prior to endoscopic ultrasonography may be recommended because epithelial neoplasms could be detected at a non-negligible rate.

The Effect of Renin-Angiotensin System Inhibitors in Patients Undergoing Pancreatic Cancer Resection.

OBJECTIVES: The local renin-angiotensin system promotes angiogenesis and proliferation via vascular endothelial growth factor or epidermal growth factor receptor expression. In this study, we aimed to evaluate the impact of angiotensin system inhibitors (ASIs) on long-term outcomes in patients undergoing surgical resection of pancreatic ductal adenocarcinoma (PDAC). METHODS: A single institutional retrospective analysis was performed using the medical records of patients who underwent pancreatic resection with curative intent for PDAC between January 2005 and December 2018. Patient characteristics and surgical outcomes were compared between patients taking ASIs and those who are not. RESULTS: A total of 272 patients were included in the study and classified into the ASI group (n = 121) and the non-ASI group (n = 151). The median overall survival times in the ASI group and non-ASI group were 38.0 and 34.0 months ( P = 0.250), and the median recurrence-free survival times were 24.0 and 15.0 months ( P = 0.025), respectively. Multivariate analysis for recurrence-free survival identified the use of ASIs ( P = 0.020), CA19-9 level >500 IU/L ( P = 0.010), positive lymph node metastasis ( P < 0.001), and no adjuvant chemotherapy ( P < 0.001) as independent prognostic factors. CONCLUSIONS: The use of ASI may improve long-term outcomes after surgery for PDAC.

Effect of Smoke Evacuator on Reduction of Volatile Organic Compounds and Particles in Surgical Smoke: A Randomized Controlled Trial.

BACKGROUND: Surgical smoke is an occupational health problem and is increasingly recognized as a potential source of virus transmission. Dedicated smoke evacuators are used to protect against surgical smoke exposure. We tested the hypothesis that using smoke evacuators would reduce volatile organic compounds and the number of particles in surgical smoke during the laparotomy procedure. STUDY DESIGN: A randomized, double-blind clinical trial was conducted in patients undergoing laparotomy from June 11, 2021, to March 30, 2022, to compare the effectiveness of smoke evacuators with a control (registration, UMIN000044250). The primary outcome was a change in the acetaldehyde level. Secondary outcomes were changes in the formaldehyde level and particle count assessed by the particle size of 0.3, 0.5, 1.0, and 5.0 nm. RESULTS: A total of 42 patients were randomized and assessed (smoke evacuator group, n = 22 vs control group, n = 20). The acetaldehyde level was significantly lower in the smoke evacuator group than in the control group: mean (95% CI), 10.6 (3.7 to 17.5) vs 47.2 (19.9 to 74.5) µg/m 3 , p < 0.001. Similarly, the formaldehyde level was 72.2% lower in the smoke evacuator group than in the control group. Particle counts by each particle size category were 80% to 95% lower in the smoke evacuator group than in the control group (all, p < 0.001). CONCLUSIONS: Dedicated smoke evacuators reduced the level of acetaldehyde and formaldehyde, and the number of particles in surgical smoke, minimizing the potential exposure to volatile organic compounds and particle matters during surgery.

Evaluation of pancreatic chymotrypsin activity for on-site prediction of clinically relevant postoperative pancreatic fistula.

OBJECTIVES: Although the risk of complications due to postoperative pancreatic fistula (POPF) have been evaluated based on the amylase level in drained ascitic fluid, this method has much room for improvement regarding diagnostic accuracy and facility of the measurement. This study aimed to investigate the clinical value of measuring pancreatic chymotrypsin activity for rapid and accurate prediction of POPF after pancreaticoduodenectomy. METHODS: In 52 consecutive patients undergoing pancreaticoduodenectomy, the chymotrypsin activity in pancreatic juice was measured by calculating the increase in fluorescence intensity during the first 5 min after activation with an enzyme-activatable fluorophore. The predictive value for clinically relevant POPF (CR-POPF) was compared between this technique and the conventional method based on the amylase level. RESULTS: According to receiver operating characteristic analyses, pancreatic chymotrypsin activity on postoperative day (POD) 3 measured with a multiplate reader had the highest predictive value for CR-POPF (area under the curve [AUC], 0.752; P < 0.001), yielding 77.8 % sensitivity and 68.8 % specificity. The AUC and sensitivity/specificity of the amylase level in ascitic fluid on POD 3 were 0.695 (P = 0.053) and 77.8 %/41.2 %, respectively. Multivariable analysis identified high pancreatic chymotrypsin activity on POD 3 as an independent risk factor for CR-POPF. Measurement of pancreatic chymotrypsin activity with a prototype portable fluorescence photometer could significantly predict CR-POPF (AUC, 0.731; P = 0.010). CONCLUSION: Measurement of pancreatic chymotrypsin activity enabled accurate and rapid prediction of CR-POPF after pancreaticoduodenectomy. This can help surgeons to implement appropriate drain management at the patient's bedside without delay.

A data-informed timeline for hospital discharge with a reasonably low risk of unplanned readmission after open and minimally invasive liver resections.

BACKGROUND: Postoperative complications following liver resection remain high, ranging from 20% to 50%. Patients are hospitalized for a certain period of time following liver resection because of the risk of postoperative complications. We hypothesized that the risk of complications decreases with each complication-free postoperative day after open and minimally invasive liver resections and can be stratified using a recently reported three-level complexity classification. METHODS: Patients undergoing first liver resection without concomitant other organ resections between 2006 and 2019 were included. The three-level complexity classification was used to categorize liver resection procedures into grades I-III. We assessed the rate of cumulative postoperative complications from the time of liver resection to the time of post-hepatectomy complications (≥ Clavien-Dindo grade II). RESULTS: Of the 911 patients included, 200 underwent resection of grade I procedures, 185 underwent resection of grade II procedures, and 526 underwent resection of grade III procedures. The risks of post-hepatectomy complications changed over time and were stratified by surgical complexity. For patients at the time of liver resection, the estimated 30-day complication rate was 21.8% for open grade I resection, 26.7% for open grade II resection, 38.4% for open grade III resection, 8.6% for laparoscopic grade I resection, and 12.5% for laparoscopic grade II resection. For patients without complications at 7 days, the estimated 30-day complication rate decreased to 2.1% for open grade I, 9.2% for open grade II, 17.6% for open grade III, 1.3% for laparoscopic grade I, and 4.5% for laparascopic grade II. CONCLUSIONS: The post-hepatectomy complication risks were stratified by surgical complexity, liver resection approach, and the period without complication after liver resection.

Two-step artificial intelligence algorithm for liver segmentation automates anatomic virtual hepatectomy.

BACKGROUND: Anatomic virtual hepatectomy with precise liver segmentation for hemilivers, sectors, or Couinaud's segments using conventional three-dimensional simulation is not automated and artificial intelligence (AI)-based algorithms have not yet been applied. METHODS: Computed tomography data of 174 living-donor candidates for liver transplantation (training data) were used for developing a new two-step AI algorithm to automate liver segmentation that was validated in another 51 donors (validation data). The Pure-AI (no human intervention) and ground truth (GT, full human intervention) data groups were compared. RESULTS: In the Pure-AI group, the median Dice coefficients of the right and left hemilivers were highly similar, 0.95 and 0.92, respectively; sectors, posterior to lateral: 0.86-0.92, and Couinaud's segments 1-8: 0.71-0.89. Labeling of the first-order branch as hemiliver, right or left portal vein perfectly matched; 92.8% of the second-order (sectors); 91.6% of third-order (segments) matched between the Pure-AI and GT data. CONCLUSIONS: The two-step AI algorithm for liver segmentation automates anatomic virtual hepatectomy. The AI-based algorithm correctly divided all hemilivers, and more than 90% of the sectors and segments.