Therapeutic biliary stents: applications and opportunities.

INTRODUCTION: Biliary stents are used to optimize ductal patency and enable bile flow in the management of obstruction or injury related to biliary tract tumors, strictures, stones, or leaks. Although direct therapeutic applications of biliary stents are less well developed, stents can be used to deliver drugs, radioisotopes, and photodynamic therapy. AREAS COVERED: This report provides an in-depth overview of the clinical indications, and therapeutic utility of biliary stents. Unique considerations for the design of biliary stents are described. The properties and functionalities of materials used for stents such as metal alloys, plastic polymers, or biodegradable materials are described, and opportunities for design of future stents are outlined. Current and potential applications of stents for therapeutic applications for biliary tract diseases are described. EXPERT OPINION: Therapeutic biliary stents could be used to minimize inflammation, prevent stricture formation, reduce infections, or provide localized anti-cancer therapy for biliary tract cancers. Stents could be transformed into therapeutic platforms using advanced materials, 3D printing, nanotechnology, and artificial intelligence. Whilst clinical study and validation will be required for adoption, future advances in stent design and materials are expected to expand the use of therapeutic biliary stents for the treatment of biliary tract disorders.

Impact of biliary stents in the performance of the EUS-guided tissue acquisition: A systematic review and meta-analysis / Impacto de los stents biliares en el rendimiento de la adquisición de biopsias guiadas por ecoendoscopia: una revisión sistemática y metanálisis

Introduction and aim: Pancreatobiliary tumours are challenging to diagnose exclusively by imaging methods. Although the optimum moment for carrying out the EUS is not well defined, it has been suggested that the presence of biliary stents may interfere with the proper staging of tumours and the acquisition of samples. We performed a meta-analysis to evaluate the impact of biliary stents on EUS-guided tissue acquisition yield. Material and methods: We conducted a systematic review in different databases, such as PubMed, Cochrane, Medline, and OVID Database. A search was made of all studies published up to February 2022. Results: Eight studies were analyzed. A total of 3185 patients were included. The mean age was 66.9±2.7 years; 55.4% were male gender. Overall, 1761 patients (55.3%) underwent EUS guided tissue acquisition (EUS-TA) with stents in situ, whereas 1424 patients (44.7%) underwent EUS-TA without stents. The technical success was similar in both groups (EUS-TA with stents: 88% vs EUS-TA without stents: 88%, OR=0.92 [95% CI 0.55–1.56]). The type of stent, the needle size and the number of the passes were similar in both groups. Conclusions: EUS-TA has similar diagnostic performance and technical success in patients with or without stents. The type of stent (SEMS or plastic) does not seem to influence the diagnostic performance of EUS-TA. Future prospectives and RCT studies are needed to strengthen these conclusions. (AU)

Introducción y objetivo: Los tumores pancreatobiliares son lesiones difíciles de diagnosticar exclusivamente por métodos de imagen. Aunque no está bien definido el momento óptimo para la realización de la ecoendoscopia (EUS), se ha demostrado que la presencia de stents biliares puede interferir en la correcta estadificación de los tumores y la toma de muestras. Realizamos un metanálisis para evaluar el impacto de los stents biliares en el rendimiento de la adquisición de tejido guiada por EUS. Material y métodos: Realizamos una revisión sistemática en diferentes bases de datos, como PubMed, Cochrane, Medline y OVID Database. Se realizó una búsqueda de todos los estudios publicados hasta febrero de 2022. Resultados: Se analizaron 8 estudios. Se incluyeron un total de 3.185 pacientes. La media de edad fue de 66,9±2,7 años; el 55,4% fueron pacientes de sexo masculino. En total, 1.761 pacientes (55,3%) se sometieron a biopsias guiadas por EUS con stents in situ, mientras que 1.424 pacientes (44,7%) se sometieron a dichas biopsias sin stents. El éxito técnico fue similar en ambos grupos (EUS con stents: 88% vs. EUS sin stents: 88%, OR=0,92 [IC 95% 0,55-1,56]). El tipo de stent, el tamaño de la aguja y el número de pases fueron similares en ambos grupos. Conclusiones: La biopsia por EUS tiene un rendimiento diagnóstico y un éxito técnico similares en pacientes con o sin stents. El tipo de stent (SEMS o plástico) no parece influir en el rendimiento diagnóstico de la adquisición de tejido guiada por EUS. Se necesitan futuros estudios prospectivos y estudios aleatorizados controlados para fortalecer estas conclusiones. (AU)

Impact of biliary stents in the performance of the EUS-guided tissue acquisition: A systematic review and meta-analysis.

INTRODUCTION AND AIM: Pancreatobiliary tumours are challenging to diagnose exclusively by imaging methods. Although the optimum moment for carrying out the EUS is not well defined, it has been suggested that the presence of biliary stents may interfere with the proper staging of tumours and the acquisition of samples. We performed a meta-analysis to evaluate the impact of biliary stents on EUS-guided tissue acquisition yield. MATERIAL AND METHODS: We conducted a systematic review in different databases, such as PubMed, Cochrane, Medline, and OVID Database. A search was made of all studies published up to February 2022. RESULTS: Eight studies were analyzed. A total of 3185 patients were included. The mean age was 66.9±2.7 years; 55.4% were male gender. Overall, 1761 patients (55.3%) underwent EUS guided tissue acquisition (EUS-TA) with stents in situ, whereas 1424 patients (44.7%) underwent EUS-TA without stents. The technical success was similar in both groups (EUS-TA with stents: 88% vs EUS-TA without stents: 88%, OR=0.92 [95% CI 0.55-1.56]). The type of stent, the needle size and the number of the passes were similar in both groups. CONCLUSIONS: EUS-TA has similar diagnostic performance and technical success in patients with or without stents. The type of stent (SEMS or plastic) does not seem to influence the diagnostic performance of EUS-TA. Future prospectives and RCT studies are needed to strengthen these conclusions.

Meta-analysis on clinical outcomes of suprapapillary versus transpapillary stent insertion in malignant biliary obstruction.

BACKGROUND/AIMS: Endoscopic biliary stenting is an essential treatment for malignant biliary obstruction (MBO). However, the optimal location for the placement of metal stents (MS) or plastic stents (PS) during the management of MBO, whether above (suprapapillary) or across (transpapillary) the sphincter of Oddi (SO), has not been thoroughly evaluated. This meta-analysis aims to compare the clinical outcomes associated with endoscopic retrograde cholangiopancreatography (ERCP)-guided biliary stents placed above and across the SO in patients with MBO. METHODS: A comprehensive search of electronic databases was carried out to identify studies published from inception to April 2022. The clinical outcomes examined including stent patency, stent occlusion, and overall adverse events (AEs) such as cholangitis, post-ERCP pancreatitis (PEP), cholecystitis, stent migration, and bleeding. The selection of a random-effects model or fixed-effects model was based on the presence of heterogeneity. RESULTS: A total of 12 articles involving 751 patients were analyzed. The findings showed that the suprapapillary approach had longer stent patency compared to the transpapillary approach (mean difference: 38.58; 95% confidence interval 16.02-61.14, P < 0.0001). Additionally, the suprapapillary approach was associated with a lower risk of stent occlusion and overall AEs (P = 0.04, P = 0.002, respectively), particularly in the incidence of PEP (P = 0.009). The incidence of cholangitis, cholecystitis, stent migration, and bleeding were similar between the suprapapillary and transpapillary approaches. The subgroup analyses indicated that suprapillary PS had a significant decrease in the incidence of stent occlusion and longer stent patency, while suprapillary MS had a significant decrease in the incidence of overall AEs and PEP than the transpapillary approach. CONCLUSION: Compared with the transpapillary approach, the suprapapillary stent had superiority in longer stent patency, lower rates of stent occlusion and overall AEs, and notably, a lower incidence of PEP. The incidence of cholangitis, cholecystitis, stent migration, and bleeding were similar between the suprapapillary and transpapillary approaches. Further large-scale randomized controlled studies are needed to confirm our findings. REGISTRATION NO: CRD42022336435.

Endoscopic therapy using a self-expandable metallic stent with an anti-migration system for postorthotopic liver transplantation anastomotic biliary stricture.

BACKGROUND: Endoscopic therapy using multiple plastic stents (MPSs) is the standard therapy for postorthotopic liver transplantation (p-OLT) anastomotic biliary stricture (ABS). However, this approach demands repeated procedures. Recent studies using fully covered self-expandable metallic stents (FCSEMS) have shown encouraging results, but migration occurs in 10% to 40% of cases. The objective of this retrospective study was to evaluate the efficacy of endoscopic treatment using FCSEMS with an anti-migration system (Am-FCSEMS) in patients with p-OLT ABS. AIM: To evaluate the efficacy of endoscopic treatment using an Am-FCSEMS in patients with p-OLT ABS. METHODS: This study was conducted in a private tertiary care centre in São Paulo, Brazil and was approved by our institution's Human Research Committee. From April 2018 to October 2020, regardless of previous endoscopic treatment (MPS or FCSEMS), 17 patients with p-OLT ABS and indications for endoscopic therapy were included in this study. The exclusion criteria were pregnancy, nonanastomotic biliary or hilar stricture, hepatic artery stenosis/thrombosis, isolated biliary fistulae, a distance shorter than 2 cm from the stricture to the hepatic hilum, and patient refusal. The primary endpoint was the efficacy of p-OLT ABS endoscopic treatment using an Am-FCSEMS that remained in place for a 12-mo period. Biliary sphincterotomy was performed in patients with native papilla, and an Am-FCSEMS (10 mm in final diameter and 60 or 80 mm in length) was placed (HanarostentTM MI Tech, Co). Balloon stricture dilation was performed only if necessary to introduce the stent. RESULTS: Three patients were excluded due to loss to follow-up before stent removal. Among the 14 patients included and followed, 7 were women, and the average age was 56 years (range: 28-76). The average period of Am-FCSEMS placement was 362 ± 109 d. Technical success occurred in all 14 patients (100%). There were no cases of distal stent migration. Complete resolution of the stricture occurred in 13/14 patients (92.85%). Adverse events occurred in 3/14 patients (21.42%): 2 patients with mild acute pancreatitis (14.28%) and 1 patient (7.14%) with stent dysfunction (occlusion by biliary sludge and stones, which was treated endoscopically without the need for stent removal). No deaths occurred related to therapy. All stents were removed using foreign body forceps or snares without difficulty. After Am-FCSEMS removal, all 13 patients who had ABS resolution were followed-up for an average of 411 ± 172 d, and there was no stricture recurrence or need for further endoscopic therapy. CONCLUSION: In this retrospective study, endoscopy therapy using an Am-FCSEMS for p-OLT ABS was safe and effective, with a high stricture resolution rate that was probably due to the absence of stent migration.

Recent developments in antibacterial or antibiofilm compound coating for biliary stents.

Cholestasis of the indwelling biliary stents usually leads to stone recurrence after endoscopic retrograde cholangio pancreatoraphy (ERCP). Biliary stents, including metallic and none-degradable plastic stents are widely used in clinical settings due to their many excellent properties. However, conventional biliary stents still suffer from poor antibacterial activity and anti-bile-adhesion, which lead to injured, local fibroblasts proliferating. Currently, various coatings for biliary stents have been prepared to meet the clinical demands. In this review, we start by summarizing and discussing classifications of biliary stents and antibacterial/antibiofilm mechanism. Then, the latest advances about developing antibacterial and antibiofilm coatings for improving the properties of biliary stents are reviewed and discussed in detail. Lastly, we list several possible directions for future development of biliary stents coatings and biliary stent, such as anti-bile-adhesion coating, multifunctional coating, drug-eluting biodegradable biliary stents and 3D printed biliary stents.

Preventive effect of biodegradable stents on biliary stricture and fibrosis after biliary anastomosis in a porcine model.

PURPOSE: The current drain tubes for preventing surgically biliary anastomotic stricture are not naturally and easily removed. If a drain tube using biodegradable material is easily available and the degradation time of the tube is well controlled, surgical anastomotic stricture and fibrosis could be prevented. The aim of this animal study was to evaluate the preventive effect of novel biodegradable stents (BS) on biliary stricture and fibrosis after duct-to-duct (DD) biliary anastomosis. METHODS: Ten mini-pigs were allocated to the control group (n = 5) and or the stent group (n = 5). The common bile duct was exposed through surgical laparotomy and then resected transversely. In the stent group, a 4-mm or 6-mm polydioxanone/magnesium sheath-core BS was inserted according to the width of the bile duct, followed by DD biliary anastomosis. In the control group, DD biliary anastomosis was performed without BS insertion. RESULTS: In the stent group, stents were observed without deformity for up to 4 weeks in all animals. Eight weeks later, histopathologic examination revealed that the common bile duct of the anastomosis site was relatively narrower in circumference in the control group compared to the stent group. The degree of fibrosis in the control group was more marked than in the stent group (3.84 mm vs. 0.68 mm, respectively; P < 0.05). CONCLUSION: Our study showed that novel BS maintained their original shape and radial force for an adequate time and then disappeared without adverse events. The BS could prevent postoperative complications and strictures after DD biliary anastomosis.

Percutaneous cholecystostomy for acute cholecystitis after stent insertion in patients with malignant biliary obstruction: clinical outcomes of 107 patients.

BACKGROUND: The outcome of percutaneous cholecystostomy (PC) in malignant patients with acute cholecystitis (AC) after biliary stent insertion has not been investigated in a large group. PURPOSE: To evaluate the clinical outcomes of PC for AC after stent insertion in patients with malignant biliary obstruction. MATERIAL AND METHODS: From April 2007 to February 2019, 107 patients (57 men, 52 women; mean age = 67.5 years; age range = 27-93 years) who had undergone PC for AC after biliary stent insertion were retrospectively evaluated. Of the 107 patients, 86 underwent biliary stent insertion by the endoscopic approach and the remaining 21 patients by the percutaneous approach. All patients were classified into three groups: those with stent-induced AC; those with cancer-induced AC; and those with AC without mechanical cause (biliary stent, GB stone, or cancer invasion). The mean survival time, recurrence rate, symptom improvement, and cystic duct patency in each patient group were analyzed. RESULTS: Stent-induced AC (n = 40, 37.4%) developed with a mean onset time of six days (range = 0-14 days), AC without mechanical cause (n = 27, 25.2%), 87 days (range = 15-273 days), and cancer-induced AC (n = 40, 37.4%), 137 days (range = 15-447 days) after stent insertion. Symptom resolution and significant improvement in laboratory test values were achieved in 95 patients (88.8%) within four days after PC. CONCLUSION: PC is a technically safe and effective method for the treatment of AC after biliary stent insertion in patients with malignant biliary obstruction.

Biliary stents are forgotten more frequently in elderly patients

Background/aim: Plastic biliary stents that remain in situ for more than 12 months, called forgotten biliary stents (FBSs), can cause complications such as cholangitis, stent migration, stent occlusion, and perforation. Materials and methods: The medical records of patients who underwent ERCP procedures from December 2016 to December 2020 were analysed retrospectively. Data on patient characteristics, indications for ERCP and stenting, stent types, stenting duration, complications, and causes of FBSs were obtained from the hospital's database. Results: A total of 48 cases with FBSs were analysed. The mean age (SD) of the patients was 71.23 years (±12.165), the male-to-female ratio was 23/25 (0.92), and the mean stenting duration was 27.12 months (range: 12­84 months). The most common indication for biliary stenting was irretrievable choledochal stones (40/48). Stone formation (79%) and proximal stent migration (26.4%) were the most frequent complications. The patients in the FBS group were significantly older than those from whom stents were removed in a timely manner (71.23 vs. 62.43 years, p < 0.001). Endoscopic treatment was possible in all cases; surgery was not required in any case. The most common cause of FBSs cited by patients was not having been informed about the need for long-term management of their stents (n = 14, 29.2%) Conclusion: FBSs are potentially problematic particularly in elderly patients. Communication with the patient to remind them of the need for stent management is important for preventing FBSs.

Personalized Endoscopy in Complex Malignant Hilar Biliary Strictures.

Malignant hilar biliary obstruction (HBO) represents a complex clinical condition in terms of diagnosis, surgical and medical treatment, endoscopic approach, and palliation. The main etiology of malignant HBO is hilar cholangiocarcinoma that is considered an aggressive biliary tract's cancer and has still today a poor prognosis. Endoscopy plays a crucial role in malignant HBO from the diagnosis to the palliation. This technique allows the collection of cytological or histological samples, direct visualization of the suspect malignant tissue, and an echoendoscopic evaluation of the primary tumor and its locoregional staging. Because obstructive jaundice is the most common clinical presentation of malignant HBO, endoscopic biliary drainage, when indicated, is the preferred treatment over the percutaneous approach. Several endoscopic techniques are today available for both the diagnosis and the treatment of biliary obstruction. The choice among them can differ for each clinical scenario. In fact, a personalized endoscopic approach is mandatory in order to perform the proper procedure in the singular patient.

Mechanical properties and degradation process of biliary self-expandable biodegradable stents.

OBJECTIVES: The clinical outcomes and prevalence of adverse events associated with biliary biodegradable stents (BS) can differ according to degradation process and time. The aim of this study was to observe the degradation process and time of different BS prototypes, and to evaluate sequential changes in their mechanical properties. METHODS: Using an in vitro bile flow phantom model, we compared degradation time, radial force changes, and morphologic changes among four different BS prototypes: polydioxanone (PDO) BS, polyglycolide (PGA) BS, polydioxanone/poly-l-lactic acid (PDO/PLLA) sheath-core BS, and polydioxaone/magnesium (PDO/Mg) sheath-core BS. Using an in vivo swine bile duct dilation model, we performed a direct peroral cholangioscopy (DPOC) examination to observe the biodegradation process and related adverse events at regular intervals. RESULTS: In the bile flow phantom model, the PGA BS and PDO/Mg BS prototypes showed rapid radial force reduction and morphological changes and complete degradation within six weeks. PDO/PLLA BS maintained high radial force and kept their original shape for longer than the PDO BS, up to 16 weeks. A total of 24 BS were inserted into the dilated bile ducts of 12 swine. In this animal model, DPOC examination revealed that PDO BS and PDO/PLLA BS maintained their original shapes for approximately 12 weeks, but PDO BS showed a greater degree of fragmentation and induced biliary stones and bile duct obstruction. CONCLUSION: Our results showed that PDO/PLLA BS maintained their original shape and radial force for a relatively long time and minimized adverse events.

Clinical Diagnosis and Treatment of Autoimmune Pancreatitis and IgG4-related Sclerosing Cholangitis / 胃肠病学

Background: Autoimmune pancreatitis (AIP) is a chronic pancreatitis associated with immune factors. IgG4-related sclerosing cholangitis (IgG4-SC) is a common extrapancreatic manifestation of AIP, however, its optimal treatment still needs to be clarified. Aims: To summarize the experience in the clinical diagnosis and treatment of AIP, especially IgG4-SC. Methods: Twenty-five patients with AIP admitted from the First Affiliated Hospital of Nanchang University between January 2015 and May 2021 were recruited, and a retrospective analysis was conducted on the clinical symptoms, laboratory and imaging findings, pathological results, as well as the treatment regimens and clinical outcomes. Results: All the patients were diagnosed as type 1 AIP (84.0% male, mean age 63.5 years). Obstructive jaundice (56.0%) and epigastric pain (44.0%) were the main clinical symptoms. The main imaging findings were diffuse enlargement of the pancreas, capsule-like rim, and distal biliary stricture associated with intra- and extra-hepatic duct dilation. The serum IgG4 elevated significantly. In 14 patients with IgG4-SC, the total bilirubin was between 1-2 upper limit of normal (ULN) in 3 cases, between 2-5 ULN in 3 cases, and > 5×ULN in 8 cases. Fifteen (83.3%) patients obtained pathological diagnosis by endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA). Six IgG4-SC patients were treated with steroids alone, and 6 received biliary stenting with or without steroids, no differences in liver function tests were existed between the two groups prior to treatment (all P> 0.05). Liver function tests in most of these patients were normalized after treatment. Conclusions: AIP is a rare disease in clinical practice, and is more frequently seen in elderly male patients. Biliary involvement (IgG4-SC) is common and often presents initially as obstructive jaundice, which can be effectively managed with steroids alone, without the need for biliary stenting.

Clinical efficacy and safety of enteral extended biliary stent in treatment of biliary stricture / 中华消化内镜杂志

Objective:To evaluate the efficacy and safety of enteral extended biliary stenting for biliary stricture.Methods:A multicenter retrospective cohort study was conducted on data of 550 patients with obstructive jaundice due to extrahepatic bile duct stricture between February 2006 and April 2020. Patients were assigned to conventional group (undergoing conventional biliary stent placement) and extended group (undergoing enteral extended biliary stent placement). Propensity score was used to match the basic data of patients of the two groups. Then the stent patency time, bilirubin difference before and after 1 week operation, incidence of complications and hospital stay were compared between the two groups.Results:Among the 550 patients, clinical data of 20 cases were missing and 35 failed to be followed up. Finally, 326 patients were enrolled to the study after propensity score matching with 163 cases in each group. The patency time of extended group was 111.0 (82.0, 192.0) days, which was longer than that of conventional group with patency time of 93.0 (70.0, 141.8) days ( Z=3.260, P=0.001). Total bilirubin difference value of pre-operation and post-operation was less in extended group [51.2 (26.0, 114.7) μmol/L VS 46.0 (13.9, 81.1) μmol/L, Z=2.095, P=0.036]. The rate of early adverse events [4.3% (7/163) VS 3.7% (6/163), P=0.079] and median in-patient days (10.0 days VS 10.0 days, P=0.379) were similar in the two groups. Conclusion:Enteral extended biliary stent is effective and safe for treatment of biliary stricture, which can prolong the patency time without increasing postoperative complications and hospital stay.

3D Printed Model of Extrahepatic Biliary Ducts for Biliary Stent Testing.

Several inflammatory conditions of the bile ducts cause strictures that prevent the drainage of bile into the gastrointestinal tract. Non-pharmacological treatments to re-establish bile flow include plastic or self-expanding metal stents (SEMs) that are inserted in the bile ducts during endoscopic retrograde cholangiopancreatography (ERCP) procedures. The focus of this study was to 3D print an anatomically accurate model of the extrahepatic bile ducts (EHBDs) with tissue-like mechanical properties to improve in vitro testing of stent prototypes. Following generation of an EHBD model via computer aided design (CAD), we tested the ability of Formlabs SLA 3D printers to precisely print the model with polymers selected based on the desired mechanical properties. We found the printers were reliable in printing the dimensionally accurate EHBD model with candidate polymers. Next, we evaluated the mechanical properties of Formlabs Elastic (FE), Flexible (FF), and Durable (FD) resins pre- and post-exposure to water, saline, or bile acid solution at 37 °C for up to one week. FE possessed the most bile duct-like mechanical properties based on its elastic moduli, percent elongations at break, and changes in mass under all liquid exposure conditions. EHBD models printed in FE sustained no functional damage during biliary stent deployment or when tube connectors were inserted, and provided a high level of visualization of deployed stents. These results demonstrate that our 3D printed EHBD model facilitates more realistic pre-clinical in vitro testing of biliary stent prototypes.

Optimal timing of pancreaticoduodenectomy following preoperative biliary drainage considering major morbidity and postoperative survival.

BACKGROUND: The present study aimed to determine the optimal timing of pancreaticoduodenectomy (PD) following preoperative biliary drainage (PBD) with consideration of postoperative morbidity and survival. METHODS: Between January 2007 and December 2015, consecutive 1,568 patients underwent PD at a single institution. Their data were reviewed retrospectively. RESULTS: Of all, 831 patients underwent PBD. The mean duration between drainage and surgery was 16.9 days. Regarding postoperative outcomes, length of hospital stay was longer in the drainage group (P = 0.028). Postoperative pancreatic fistula was not significantly different between the non-drainage and drainage groups (P = 0.162), but major complications occurred more frequently in the drainage group (P = 0.002). Multivariable analysis showed major complications occurred significantly at third and fourth weeks (odds ratios 1.863 and 2.523) after PBD, whereas early surgery performed in the first 2 weeks did not noticeably increase postoperative complications. In multivariable survival comparison, weekly interval beyond 6 weeks was associated with poor survival in those with pancreatic cancer, while patients with bile duct cancer operated on at the fourth week showed worse prognosis. CONCLUSIONS: Early surgery that reduces the operative delay after PBD may improve both short- and long-term postoperative outcomes in cancer patients undergoing PBD.

Biliary injuries after pancreatic surgery: interventional radiology management.

Bile duct injuries are among the most feared complications after pancreatic surgery. Most of these surgical complications are related to iatrogenic injuries and include bile leakage, biliary duct obstruction or stricture and infection. A wide range of Interventional Radiology treatment options are currently available. The options include percutaneous transhepatic cholangiography (PTC), percutaneous transhepatic biliary drainage (PTBD), percutaneous balloon dilatation and stenting, image-guided percutaneous abscess drainage. The purpose of this review is to describe the current evidence in this continuously evolving field.

Percutaneous Patency Recovery and Biodegradable Stent Placement in a Totally Occluded Hepaticojejunostomy After Paediatric Living Donor Liver Transplantation.

Biliary complications after living donor liver transplantation (LDLT) cause severe morbidity and mortality, with biliary anastomotic stricture being the most common form of presentation. Surgical revision is risky, and it is avoided whenever possible. When a Roux-en-Y hepaticojejunostomy (RYHJ) is used for bilioenteric reconstruction, endoscopic approach is more difficult, if not impracticable. Therefore, percutaneous approach remains as a first-line treatment in these patients. In this case presentation, a percutaneous approach was used to recover patency in an intractable, totally occluded RYHJ stricture in an LDLT paediatric recipient, using a Rösch-Uchida needle to access to the collapsed jejunal loop from the bile duct. Once recanalization of the RYHJ was achieved, a biodegradable stent was placed with middle-term patency at follow-up.

The effect of biliary stent position on short?term and long?term outcomes of patients with low malignant obstructive jaundice after surgical treatment / 中国综合临床

Objective To explore the effect of the position of the biliary stents on the short?term and long?term effects of the patients with low malignant obstructive jaundice after treatment.Methods Seventy?eight patients with low?grade malignant obstructive jaundice diagnosed in Jiangyin Hospital Affiliated to Medical College of Southeast University who underwent biliary stenting were enrolled as the study object.According to the placement of the biliary stents,the stents were divided into the spanning group and the non?crossing group.The baseline data and related serological indexes were recorded,and the changes of jaundice between the two groups were compared by repeated measurements.All patients were followed up for 48 weeks.Multivariate Cox regression analysis was applied on the risk factors that might affect the prognosis of patients, and the degree of influence of various factors on the prognosis of patients was further evaluated.Results Repeated measures analysis showed that the biochemical indicators of the spanning group and the non?crossing group showed a significant downward trend and the difference was statistically significant (TBil: Fintra?group＝9.392,Pintra?group＝0.000; DBil: Fintra?group＝7.581,Pintra?group＝0.001).Among them,the total bilirubin (TBil) (Preoperative: (318.69±101.13) μmol／L,1 week after surgery: (135.98 ±63.61) μmol／L,2 weeks after surgery: (60.21±24.81) μmol／L) was lower than the non?crossing group preoperative: (309.07±109.97) μmol／L,1 week after surgery: (158.87±66.92) μmol／L,2 weeks after surgery: (75.91 ± 20.46) μmol／L), and the difference was statistically significant ( Finter?group ＝3.362, Pinter?group＝0.041).The direct bilirubin ( DBil) ( Preoperative: (171.93 ± 73.01) μmol／L,1 week after surgery: (90.38± 57.33) μmol／L,2 weeks after surgery:(36.64± 18.95) μmol／L) was lower than the non?crossing group ( Preoperative: ( 174.53 ± 82.74) μmol／L,1 week after surgery: ( 107.85 ± 49.07) μmol／L,2 weeks after surgery: ( 37.87 ± 14.55 ) μmol／L.The difference was statistically significant (Finter?group＝6.284,Pinter?group＝0.003).There was an interaction between the treatment regimen and treatment time (1 week after surgery and 2 weeks after surgery) (TBil: Finteraction＝12.262,Pinteraction＝0.000; DBil:Finteraction＝10.254,Pinteraction＝0.000).The results of the multi factor Cox proportional hazard model of the spanning group and the non?crossing group showed that the ALP, DBil, TBil and lymphatic metastasis of malignant tumor were the two independent risk factors that affect the prognosis.However, the pancreatic cancer,ALT and age in the spanning group across the ampulla also have a certain effect on the prognosis of the patients.Conclusion The effect of the placement of biliary stents across the Vater ampullary was more obvious in the short term on the decline of bilirubin.But in the long term,there was no significant difference in the prognosis of patients with biliary stenting position.ALP,TBil,DBil,and disease classification were all important risk factors affecting the prognosis of two groups of patients

Characterization of biofilms in biliary stents and potential factors involved in occlusion.

AIM: To quantify the components in biofilms and analyze the predisposing factors involved in occlusion of biliary stents. METHODS: In a prospective study conducted from April 2011 to March 2014 at a tertiary care hospital, all consecutive patients who required endoscopic biliary stent exchange/removal were included. Etiology of the biliary disease was diagnosed by imaging, cytology and on follow-up. Clinical details of patients with biliary stent retrieval were noted. All extracted stents were collected in sterile containers and immediately processed for quantification of biofilm proteins and polysaccharides. Molecular identification of commonly known and unknown bacteria was performed by polymerase chain reaction and density gradient gel electrophoresis methods. RESULTS: Eighty one patients (41 males) with age range of 20-86 years were studied. The underlying causes for stent insertion were bile duct stones (n = 46; 56.8%) benign stricture (n = 29; 35.8%) and malignancy (n = 6; 7.4%) with cholangitis in 50 (61.7%) patients. The retrieved stent sizes were 7 Fr (n = 62; 76.5%) and 10 Fr (n = 19; 23.5%) with 65 days median insertion duration. Polybacterial consortia were detected in 90.1% of the stents. The most common bacteria identified by polymerase chain reaction alone and/or sequencing were Pseudomonas (n = 38), Citrobacter (n = 23), Klebsiella (n = 22), Staphylococcus (n = 20), Serratia (n = 16), Escherichia coli (n = 14), Streptococcus (n = 13), Enterococcus (n = 13), Aeromonas (n = 12), Proteus (n = 10) and Enterobacter (n = 9). Protein concentration according to gender (0.547 ± 0.242 mg/mL vs 0.458 ± 0.259 mg/mL; P = 0.115) as well as age > 60 years and < 60 years (0.468 ± 0.295 mg/mL vs 0.386 ± 0.238 mg/mL; P = 0.205) was non-significant. However, polysaccharide concentration was significant both according to gender (0.052 ± 0.021 mg/mL vs 0.049 ± 0.016 mg/mL; P < 0.0001) and age (0.051 ± 0.026 mg/mL vs 0.038 ± 0.016 mg/mL; P < 0.011). Protein concentration in the biofilm was significantly higher (0.555 ± 0.225 mg/mL vs 0.419 ± 0.276 mg/mL; P = 0.018) in patients with cholangitis, lower (0.356 ± 0.252 mg/mL vs 0.541 ± 0.238 mg/mL; P = 0.005) in the 10 Fr group than the 7 Fr group, and significantly higher (0.609 ± 0.240 mg/mL vs 0.476 ± 0.251 mg/mL; P = 0.060) in stents of ≥ 6 mo of indwelling time. However presence/absence of cholangitis, size of stent, indication of stent insertion and indwelling time did not affect the quantity of polysaccharide concentration. CONCLUSION: Plastic stents retrieved from patients with biliary tract disease showed polymicrobial organisms with higher protein content among patients with cholangitis and those with smaller diameter stents. Longer indwelling duration had more biofilm formation.

Bending behaviors of fully covered biodegradable polydioxanone biliary stent for human body by finite element method.

This paper presents a study of the bending flexibility of fully covered biodegradable polydioxanone biliary stents (FCBPBs) developed for human body. To investigate the relationship between the bending load and structure parameter (monofilament diameter and braid-pin number), biodegradable polydioxanone biliary stents derived from braiding method were covered with membrane prepared via electrospinning method, and nine FCBPBSs were then obtained for bending test to evaluate the bending flexibility. In addition, by the finite element method, nine numerical models based on actual biliary stent were established and the bending load was calculated through the finite element method. Results demonstrate that the simulation and experimental results are in good agreement with each other, indicating that the simulation results can be provided a useful reference to the investigation of biliary stents. Furthermore, the stress distribution on FCBPBSs was studied, and the plastic dissipation analysis and plastic strain of FCBPBSs were obtained via the bending simulation.