Biliary Stent Implantation Research Articles

Mechanism and endoscopic-treatment-induced evolution of biliary non-anastomotic stricture after liver transplantation revealed by single-cell RNA sequencing.

Biliary complications, especially non-anastomotic stricture (NAS), are the main complications after liver transplantation. Insufficient sampling and no recognized animal models obstruct the investigation. Thus, the mechanisms and alterations that occur during endoscopic treatment (ET) of NAS remain unclear. Samples were obtained with endoscopic forceps from the hilar bile ducts of NAS patients receiving continuous biliary stent implantation after diagnosis. Retrospective analysis of multiple studies indicated that the duration of ET for NAS was approximately 1-2 years. Thus, we divided the patients into short-term treatment (STT) and long-term treatment (LTT) groups based on durations of less or more than 1 year. Samples were subjected to single-cell RNA sequencing. Transcriptomic differences between STT and normal groups were defined as the NAS mechanism. Similarly, alterations from STT to LTT groups were regarded as endoscopic-treatment-induced evolution. In NAS, inflammation and immune-related pathways were upregulated in different cell types, with nonimmune cells showing hypoxia pathway upregulation and immune cells showing ATP metabolism pathway upregulation, indicating heterogeneity. We confirmed a reduction in bile acid metabolism-related SPP1+ epithelial cells in NAS. Increases in proinflammatory and profibrotic fibroblast subclusters indicated fibrotic progression in NAS. Furthermore, immune disorders in NAS were exacerbated by an increase in plasma cells and dysfunction of NK and NKT cells. ET downregulated multicellular immune and inflammatory responses and restored epithelial and endothelial cell proportions. This study reveals the pathophysiological and genetic mechanisms and evolution of NAS induced by ET, thereby providing preventive and therapeutic insights into NAS. For the first time, single-cell transcriptome sequencing was performed on the bile ducts of patients with biliary complications. scRNA-seq analysis revealed distinct changes in the proportion and phenotype of multiple cell types during Nonanastomotic stricture (NAS) and endoscopic treatment. A reduction in bile acid metabolism-related SPP1+ epithelial cells and VEGFA+ endothelial cells, along with explosive infiltration of plasma cells and dysfunction of T and NK cells in NAS patients. SPP1+ macrophages and BST2+ T cells might serve as a surrogate marker for predicting endoscopic treatment.

Utility of enteral nutrition via percutaneous transhepatic cholangiography drainage catheterization in late-stage malignant obstructive jaundice

Objective: The purpose of this study was to explore the clinical benefits of establishing an enteral nutrition (EN) pathway via percutaneous transhepatic cholangiography drainage (PTCD) catheterization in patients with late-stage malignant obstructive jaundice (MOJ).Methods: We selected 30 patients diagnosed as having late-stage MOJ with malnutrition. A dual-lumen biliary-enteral nutrition tube was placed via PTCD along with a biliary stent implantation. Postoperative EN was provided, and we observed the time taken for tube placement, its success rate, complications, and therapeutic efficacy.Results: Tube placement was successful in all 30 patients with an average procedural time of 5.7 ± 1.4 min with no tube placement complications. Compared to preoperative measures, there was a significant improvement in postoperative jaundice reduction and nutritional indicators one month after the procedure (p < 0.05). Post-placement complications included tube perileakage in 5 cases, entero-biliary reflux in 4 cases, tube blockage in 6 cases, tube displacement in 4 cases, accidental tube removal in 3 cases, and tube replacement due to degradation in 8 cases, with tube retention time ranging from 42 to 314 days, averaging 124.7 ± 37.5 days. All patients achieved the parameters for effective home-based enteral nutrition with a noticeable improvement in their quality of life.Conclusion: In this study, we found that the technique of establishing an EN pathway via PTCD catheterization was minimally invasive, safe, and effective; the tube was easy to maintain; and patient compliance was high. It is, thus, suitable for long-term tube retention in patients with late-stage MOJ.

Research progress on biliary stents

Bile duct stenosis is a common condition in gastroenterology and hepatobiliary surgery and can be divided into benign stenosis and malignant stenosis according to different etiologies. The implantation of a gall stent into the site of the stenosis or obstruction is currently an important means of treating the bile duct stenosis. Biliary stents encompass two main types: plastic stents and metal stents. In recent years, biodegradable biliary stents and drug-eluting stents have also emerged. The material and structure of biliary stents have an important influence on their performance. In this paper, the research progress on biliary stent implantation technology in the treatment of biliary stenosis is reviewed. Besides, the advantages and disadvantages of biliary stents made from different materials and structures, along with their respective indications are summarized, and the development trend of degradable biliary stents is prospected.

Iodine-125 Seed Strand Implantation Combined with Biliary Stent for the Treatment of Malignant Obstructive Jaundice

Extrahepatic or intrahepatic bile duct stenosis and obstruction can lead to malignant obstructive jaundice (MOJ). Surgical treatment is an effective method, but for patients who cannot undergo surgery or miss the opportunity for surgery, biliary stent combined with 125I implantation can improve obstruction symptoms, relieve biliary obstruction, and improve liver function. This study was to investigate the efficacy of 125I implantation, single biliary stent and percutaneous transhepatic drainage (PTCD) in the treatment of MOJ. 107 patients with MOJ were included. Thirty-seven patients (study group) received biliary stent implantation of 125I particle radiotherapy drainage tube, and 35 patients (sem group) received biliary stent implantation of ordinary drainage tube. 35 patients (PTCD group) underwent PTCD interventional surgery. Biliary stenosis site, Child-Pugh grade and malignant tumor were recorded in the three groups. The changes of liver function before and after treatment were detected, and the survival time, stent patency time, and the occurrence of complications were recorded. All three groups achieved technical success. Liver function was improved in all patients (TBIL, DBIL and ALT were significantly decreased, and P values were all less than 0.05). This study demonstrates that 125I seed beam implantation combined with biliary stent implantation can be considered a safe treatment option for patients with MOJ. This treatment can improve median overall survival, improve liver function, prolong stent patency time.

A novel peroral choledochoscope was used to remove a proximal displaced stent-stone complex.

Biliary stent implantation is an effective way to treat complex biliary calculi [1] [2]. Stent displacement and stent-stone complex formation are adverse events of long-term biliary stent retention. We demonstrate a case of the use of a retrieval basket to remove a proximal displaced stent-stone complex under direct vision assisted with a novel peroral choledochoscope (eyeMax Choledochoscope System Digital Controller; Micro-Tech, Nanjing, China).

Percutaneous transhepatic cholangial drainage/percutaneous transhepatic biliary stent implantation for treatment of extrahepatic cholangiocarcinoma with obstructive jaundice

Percutaneous transhepatic cholangial drainage/percutaneous transhepatic biliary stent implantation for treatment of extrahepatic cholangiocarcinoma with obstructive jaundice

Bending the distal tip of a guidewire aids in cannulation of an occluded uncovered biliary metal stent.

Biliary metal stent implantation is an effective treatment for malignant obstructive jaundice. But it's well known that stents put in for a long time can become occluded and cause jaundice and cholangitis. At this time, endoscopic intervention is usually required to replace the stent or re-insert the stent. Re-cannulation for metal stent occlusion is challenging because the guide wire may pass through the side holes of the uncovered metal stents, resulting in prolonged surgical time and exposure to radiation. Here we present a small tip that may help endoscopists complete the re-cannulation of an uncovered metal stent in a very short time.

Percutaneous biliary stent combined with brachytherapy for malignant obstructive jaundice: a multicenter retrospective controlled study

Objective: To investigate the efficacy, safety and prognostic factors of percutaneous biliary stent combined with iodine-125 seed chain brachytherapy (radiotherapy) in the treatment of malignant obstructive jaundice. Methods: Data of 107 cases with malignant obstructive jaundice treated with percutaneous biliary stent implantation from January 2017 to December 2020 were retrospectively analyzed. Among them, 58 cases received biliary stent combined with iodne-125 seed chain brachytherapy (study group), and 49 cases received biliary stent implantation (control group). The changes of bilirubin, stent patency time, complications, overall survival (OS) and prognostic factors were analyzed in both groups. Results: The incidence of complications in the study group and the control group were 17.2% and 18.3% respectively, and the difference was not statistically significant (P=0.974). Serum total bilirubin levels were decreased significantly in both groups at one month after surgery (P<0.001). Postoperative stent patency time was significantly better in the study group (10.0±1.6 months) (95% CI: 8.2～12.5) than that in the control group (5.2±0.4 months) (95% CI: 4.1～6.0, P<0.001). The median OS was longer in the study group (11.2±1.8 months) (95% CI: 9.2～12.8) than that in the control group (8.0±1.1 months) (95% CI: 8.0～12.8, P<0.001). Multivariate analysis result showed that stent combined with brachytherapy (HR=0.08, 95% CI:0.04～0.15, P<0.001) and receiving further anti-tumor therapy after surgery (HR=0.27, 95% CI:0.15~0.49, P<0.001) were independent risk factors affecting the patency of biliary stents. Preoperative percutaneous transhepatic biliary drainage (HR=0.46, 95%CI:0.28～0.74, P=0.002), stent combined with brachytherapy (HR=0.23, 95%CI:0.14～0.39, P<0.001) and receiving further anti-tumor therapy after surgery (HR=0.37, 95%CI:0.22～0.61, P<0.001) were independent risk factors affecting OS. Conclusion: Percutaneous biliary stent combined with brachytherapy is safe and effective in the treatment of malignant obstructive jaundice, which can significantly prolong the patency time of biliary stent and the survival time of patients.

Design and Optimization of a New Anti-reflux Biliary Stent With Retractable Bionic Valve Based on Fluid-Structure Interaction Analysis.

Duodenal biliary reflux has been a challenging common problem which could cause dreadful complications after biliary stent implantation. A novel anti-reflux biliary stent with a retractable bionic valve was proposed according to the concertina motion characteristics of annelids. A 2D equivalent fluid-structure interaction (FSI) model based on the axial section was established to analyze and evaluate the mechanical performances of the anti-reflux biliary stent. Based on this model, four key parameters (initial shear modulus of material, thickness, pitch, and width) were selected to investigate the influence of design parameters on anti-reflux performance via an orthogonal design to optimize the stent. The results of FSI analysis showed that the retrograde closure ratio of the retractable valve primarily depended on initial shear modulus of material (p < 0.05) but not mainly depended on the thickness, pitch, and width of the valve (p > 0.05). The optimal structure of the valve was finally proposed with a high retrograde closing ratio of 95.89%. The finite element model revealed that the optimized anti-reflux stent possessed improved radial mechanical performance and nearly equal flexibility compared with the ordinary stent without a valve. Both the FSI model and experimental measurement indicated that the newly designed stent had superior anti-reflux performance, effectively preventing the duodenobiliary reflux while enabling the bile to pass smoothly. In addition, the developed 2D equivalent FSI model provides tremendous significance for resolving the fluid-structure coupled problem of evolution solid with large deformation and markedly shortens the calculation time.

A New Biodegradable Stent to Improve the Management of Biliary Strictures in Pediatric Split Liver Transplantation.

Cholestasis due to benign biliary strictures is the most common biliary complication after pediatric split liver transplantation (SLT), decreasing graft survival, but consensus about its management lacks. Percutaneous transhepatic cholangiography, bilioplasty and internal-external biliary drainage (IEBD) are standard treatments. The aim of this report is to present the preliminary experience with a new biodegradable biliary stent in the management of post-SLT biliary strictures. Between September 2020 and April 2021, SLT patients with a single anastomotic benign biliary stricture underwent percutaneous transhepatic implantation of an innovative 10F helical-shaped biodegradable biliary stent, featuring a slow degradation profile, in addition to the standard treatment with bilioplasty and IEBD. The device is unique and the first to be CE-marked for the use in this indication. Six pediatric patients (4 males; median age 8.6years, interquartile range 3.7years)underwent percutaneous stent implantation, without complications nor clinical cholestasis during a median follow-up of 271days (IQR 120.25). Stent dislodgement occurred in one case. Preliminary data suggest that implantation of a new biodegradable biliary stent may be considered in the management of post-SLT cholestasis in pediatric patients. Some technical tips are useful during implantation. This device may prolong biliary drainage, potentially relieving the discomfort of long-term IEBD.

Utility of endoscopic ultrasound-guided fine-needle aspiration in pancreatic cancer patients who failed to obtain a pathological diagnosis in surgical exploration.

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) allows for the analysis of diagnostic tissue specimens from various regions. For pancreatic tumors, especially un-resectable ones, how to obtain pathological confirmation is important for determining sub-sequent treatment. The purpose of this study is to investigate the clinical utility of EUS-FNA in patients who failed to obtain a pathological diagnosis in surgical exploration. Patients who underwent EUS-FNA due to unsuccessful biopsy in surgical exploration in our center were retrospectively reviewed. All of the patients were diagnosed with resectable disease before surgery but were found to be unresectable during surgery. The positive rate of pathological diagnosis of EUS-FNA was analyzed. A total of 11 patients were included in this study, among which 8 were males and 3 were females. The median age of the patients was 55 years (range, 48 to 73 years). The median lesion size was 34 mm (range, 25 to 44 mm). The median number of needle passes was 3 (range, 1 to 3). Two patients underwent biliary stent implantation while 3 patients underwent gastrojejunostomy before EUS-FNA. The technical success rate of EUS-FNA was 100% (11/11); 10 (90.9%, 10/11) samples were positive and 1 was negative (being inadequate). Intraoperative biopsy is the first choice diagnostic modality for unresectable pancreatic neoplasms. However, for patients who fail to obtain a pathological diagnosis in surgical exploration, EUS-FNA is still worth an attempt.

Construction of ultrasmooth PTFE membrane for preventing bacterial adhesion and cholestasis

Bacterial adhesion and bile sludge accumulation can increase the risk of complications such as stent restenosis after biliary stent implantation. Compared with active and passive antimicrobial surfaces, a significant advantage of slippery liquid-infused porous surfaces (SLIPSs) is their recoverable anti-adhesive properties. According to the mechanism of SLIPSs and the application environments of the biliary system, a polytetrafluoroethylene (PTFE) electrospun fibrous membrane-impregnated silicone-oil system was developed to construct an ultrasmooth surface. Experimental results indicated that a PTFE SLIPS with 350 cSt of silicone oil had an extremely small roll angle (< 5°) and a high slip rate (4.8 ± 0.1 mm/s) and maintained excellent sliding stability after 7 d of immersion in model bile system. Thus, it can inhibit the adhesion of proteins, Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, and bile sludge. Moreover, when human fibroblasts were cultured on the PTFE SLIPS, it exhibited good cytocompatibility. Therefore, the proposed ultrasmooth PTFE membranes provide a promising alternative for biliary system to prevent bacterial adhesion and bile sludge accumulation.

Performance of plastic stents used for benign and malignant biliary strictures: experience of a single high‑volume endoscopy unit.

Endoscopic plastic biliary stenting has been used for more than 30 years as a temporary or definitive treatment of benign and malignant neoplasms. These stents are commonly available, inexpensive, and easy to implant. We aimed to evaluate the duration of plastic stent patency, to assess complications associated with stent use, and to determine the optimal timing of stent replacement depending on the indication for biliary stenting. This was a retrospective cohort study with a 5‑year follow‑up including patients who underwent plastic biliary stent implantation between 2012 and 2013 in a tertiary referral gastroenterological center. The performance of stents was assessed on the basis of medical records, direct contact with patients or their family members, and information derived from the national death registry. We assessed 830 biliary stenting procedures performed in 346 patients. The indications for biliary stenting included choledocholithiasis in 120 patients (34.7%), benign stricture in 70 patients (20.2%), and malignant stricture in 156 patients (45.1%). The mean duration of stent patency for these conditions was 110, 106, and 55 days, respectively (P <0.001). Stents implanted for malignant perihilar strictures had a shorter duration of patency than those used for distal strictures (40 days vs 76 days, P = 0.002). The patency of plastic stents depends on the underlying disease. In patients with benign biliary disease, stent replacement is recommended after about 3.5 months. In patients with cancer, the timing of stent replacement should be guided by survival prognosis and location of stricture.

A Comparative Study of Self-Expandable Metallic Stent Combined with Double 125I Seeds Strands or Single 125I Seeds Strand in the Treatment of Advanced Perihilar Cholangiocarcinoma with Malignant Obstructive Jaundice.

PurposeThe purpose of this study was to compare the safety and effectiveness of a self-expandable metallic stent (SEMs) with a novel brachytherapy biliary drainage catheter (BBDC, double 125I seeds strands) or a single 125I seeds strand in the treatment of advanced perihilar cholangiocarcinoma (pCCA) with malignant obstructive jaundice (MOJ).MethodsFrom September 2016 to December 2018, we retrospectively enrolled patients with biliary stent implantation after receiving either BBDC loaded with 125I seeds (double-strands irradiation group) or an 125I seed strand treatment (single-strand irradiation group, control group). The outcomes were analyzed regarding the relief of obstructive jaundice, and interventional-related complications. Moreover, the Kaplan–Meier method was used to analyze stent patency and survival.ResultsThe success rate of interventional therapy in both groups was 100%, and all patients with MOJ were alleviated. According to the Common Terminology Criteria for Adverse Events (CTCAE 4.02), the grade 3 or 4 complications in the BBDC group and in the control group were 6/34 (17.65%) and 7/39 (17.95%), respectively (P > 0.05). The median and mean overall stent patency of the BBDC group and the control group were 207 days versus 180 days, 204.212 days versus 186.278 days (P = 0.043). The median and mean overall survivals in the BBDC group were higher than those in the control group (245 days versus 212 days, 244.883 days versus 221.844 days, P = 0.030).ConclusionThis interim analysis showed that BBDC (double-stranded irradiation) can prolong the stent patency time compared with 125I seed strand treatment (single-stranded irradiation) and had the advantage of reducing jaundice, which seemed to extend the survival period of advanced pCCA.

Anticancer Effect of Biodegradable Magnesium on Hepatobiliary Carcinoma: An In Vitro and In Vivo Study.

Biliary-stent implantation has become an effective treatment for patients with malignant obstructive jaundice caused by hepatobiliary carcinoma. Stent restenosis due to tumor ingrowth is a common problem. In this study, we assessed a biodegradable form of magnesium (Mg) for its anticancer effect on hepatobiliary carcinoma, compared to the conventional stent material of titanium (Ti). The results showed that a Mg extract inhibited proliferation and induced apoptosis in human cholangiocarcinoma cells, while a Mg plate inhibited cell adhesion and destroyed the cytoskeleton in the process of biodegradation. In animal experiments with H22 tumor-bearing mice, Mg wires implanted in tumors exhibited an inhibitory effect on their growth compared with Ti wires. Fifteen days after implantation of metal wires, the mean tumor volume and weight in the Mg group were significantly smaller than in the Ti group. We observed the dynamic-degradation process of Mg wires in tumors and generation of H2 gas via soft X-ray photography and scanning electron microscopy. Histopathological analyses showed that apoptosis of tumor cells around Mg wires significantly increased, expression of carbonic anhydrase 9 significantly decreased, and the upstream protein hypoxia-inducible factor 1-alpha also decreased to some extent. Taken together, these results indicated that biodegradable Mg had antitumor properties both in vitro and in vivo, suggesting its potential application as a novel material for biodegradable biliary stents.

Research Progress of Antibacterial Biliary Stent

Biliary stent has been widely used in the treatment of biliary stricture and obstruction, it can relieve the pain of patients effectively, but bacterial infection and stent obstruction are still troublesome after surgery. We introduce the mechanism of infection and stent blockage caused by bacterial invasion after biliary stent implantation, and expound the formation mechanism of bacterial biofilm and bile sludge in this review. Antibacterial biliary stent is an effective way to inhibit biliary tract infection, the literatures on antibacterial modification of biliary stent with different antibacterial methods in domestic and abroad are reviewed, and the research prospect of antibacterial biliary stent is summarized and prospected.

131I radioactive self-expandable metallic stents for the therapy of malignant biliary obstruction

Biliary stent implantation has become a standard approach for patients with unresectable malignant biliary obstruction. Unfortunately, in-stent restenosis after stent implantation still occurs because of tumor overgrowth. The majority of studies show that radioactive stents harbor both the obstructed biliary tract-dilating and tumor-suppressing functions. In this study, we designed a kind of novel 131I-labeled radioactive self-expandable metallic stent (SEMS) that combines the mechanical dilation forces induced by stent expansion and 131I intraluminal brachytherapy, which was prepared by first coating the SEMS with poly (diallyl acrylate) (PDA) and then labeling with iodine-131. The designed stents would not only have a longer patency time but also is able to inhibit biliary compression caused by tumor growth. The PDA coating was robust and flexible. The 131I labeling rate was about 60%, and after a 16-day test of radiochemical stability of 131I, the radioactive stability was around 80%. In addition, the radiochemical stability of 131I could be improved by PDA recoating post-131I labeling. In conclusion, we designed and fabricated a kind of novel 131I-labeled radioactive self-expandable metal stents by labeling 131I on the PDA-coated stent. We provide a new idea of radioactive stents design, which would extend the patency time of the stent while reducing the rate of stent restenosis after implantation.

Unexpected cause of dilatation of the pancreatic duct

A 71-year-old man was admitted to our department because of dilatation of the main pancreatic duct. He had a medical history of recurrent cholecystitis, cholangiolithiasis, and cholangitis. His symptoms improved after endoscopic treatment, and a history of biliary stent implantation was reported during this period.

Progress in the Application of Interventional Technique in Malignant Obstructive Jaundice

Malignant obstructive jaundice (MOJ) is usually due to the terminal stages of tumor, so there is no time for curative surgery. Hyperbilirubinemia caused by MOJ can cause damage to systems throughout the body and affect the survival prognosis. Symptomatic treatment is needed even in the advanced stage of the disease. Interventional therapy and surgery are the main means to relieve biliary obstruction, but patients have poor tolerance to surgery at this time, and the risk of surgery is high. At this time, the focus of treatment is to remove the obstruction of the biliary tract as early as possible to avoid the further aggravation of jaundice, progressive deterioration of liver function and other serious complications. Biliary interventional therapy has the special advantage of minimally invasive, and is an effective treatment for patients with advanced MOJ. Currently, bile duct interventional therapy mainly includes bile duct interventional drainage, biliary stent implantation, iodine-125 (¹²⁵ I) seed strand implantation, biliary radiofrequency ablation（RFA）and Intraluminal brachytherapy (ILBT), etc. Each of which has its own advantages and disadvantages in clinical application. With the progress of medical technology and the improvement and perfection of hardware equipment, the combination of multiple clinical departments and multiple operation methods will become a new trend of MOJ interventional therapy.

Absorbable stents for treatment of benign biliary strictures: long-term follow-up in the prospective Spanish registry.

Benign strictures of the bile duct may be difficult to treat endoscopically due to altered bowel anatomy. Furthermore, recurrence of stenosis and symptoms remains high. The aim of the Spanish Prospective Registry BiELLA study was to investigate the safety and efficacy of absorbable stents in the treatment of benign biliary strictures and their outcomes on the medium and long-term follow-up. A prospective, multicenter, observational, non-randomized study (the BiELLA study) was conducted from January 2014 to September 2018. One hundred fifty-nine patients with benign biliary strictures, mostly postsurgical, were enrolled for implantation of absorbable biliary stents in the 11 participating Spanish tertiary hospitals. The average patient follow-up was 45.4 ± 15.9months (range, 12-60months). The follow-up data included symptoms, biochemical parameters, and ultrasound images at 1, 6, and 12months and then yearly for up to 60months. The immediate technical and clinical success rates were 100%. In all patients, stent placement resulted in improvement of clinical symptoms and biochemical parameters. The primary mean patency for stent was 86.7, 79.6, and 78.9% at 12, 36, and 60months, respectively (95% CI). Biliary restenosis and occlusion occurred in 40 (26.6%) patients. Of the 40 patients, 18 (12%) patients were treated with a second stent and 22 (14.6%) patients had operative repair of the recurrent strictures. There were no major complications associated with stent implantation. Implantation of an absorbable polydioxanone biliary stent is safe and effective for treatment of benign biliary strictures refractory to balloon dilatation or other biliary intervention. • Percutaneous implantation of biodegradable prostheses for the treatment of benign postsurgical biliary strictures is a safe and effective procedure. • More than 75% of the patients presented patency of the stented biliary tree at 5years follow-up. • Absorbable stents improved clinical symptoms and signs (jaundice, itching, fever), and laboratory parameters in a few days after stent placement.