Analysis of biliary microbiota in experimental pigs before and after enteral extended biliary stents implantation / 中华消化内镜杂志

Objective:To compare the changes of biliary microbiota after enteral extended biliary stents (EEBS) implantation with that of conventional plastic stents in animal experiment, and to preliminarily investigate its possible mechanism in preventing stents occlusion.Methods:A total of 12 healthy Bama minipigs were randomly assigned to the conventional plastic stent group ( n=6) and the EEBS group ( n=6) using simple random method. The bile samples of all pigs were collected before stents implantation and 4 weeks after stents placement. The biliary microbiota composition and diversity before and after different stents implantation were analyzed by 16S rRNA gene sequencing and compared. Results:No complications including acute cholangitis, perforation, bleeding, or death occurred in 12 pigs. Eight days after stents implantation, stents were out of bile duct in all pigs under endoscopy, while the bile samples were collected again for analysis. The main composition of biliary microbiota at the phylum level were Proteobacteria, Firmicutes and Bacteroidota. Alpha-diversities revealed the Shannon ( P=0.004) and Simpson index ( P=0.008) significantly decreased in the conventional stent group after stents placement, and Bata diversity analysis also showed a significant difference in microbial composition (Anosim: R=0.514 8, P=0.011). There was no significant difference in Observed species index ( P=0.095), Chao1 index ( P=0.136), Shannon index ( P=0.353), Simpson index ( P=0.227) or Bata diversity (Anosim: R=0.059 3, P=0.187) in the EEBS group before and after stents placement. LEfSe algorithm indicated Bacteroides_ fragilis and Proteobacteria- Gammaproteobacteria- Enterobacterales- Enterobacteriaceae- scherichia_ Shigella- Escherichia_ coli significantly increased in the conventional stent group, and Desulfobacterota- Desulfovibrionia- Desulfovibrionales- Desulfovibrionaceae- Bilophila significantly increased in the EEBS group after stents placement. Conclusion:The biliary microbiota change slightly after EEBS implantation in the short-term, and EEBS may prevent duodenobiliary reflux by prolonging the reflux path.

Clinical effect of different plastic biliary stent indwelling methods on managing obstructive jaundice in unresectable hilar cholangiocarcinoma / 中华消化内镜杂志

Objective:To compare the clinical effect of three indwelling methods of plastic biliary stent on relieving obstructive jaundice caused by unresectable hilar cholangiocarcinoma.Methods:A retrospective study was performed on data of 61 patients with obstructive jaundice caused by unresectable hilar cholangiocarcinoma from April 2014 to December 2020 in Cancer Hospital, Chinese Academy of Medical Sciences. Plastic biliary stent placement was used to relieve jaundice, including 18 cases of intragastric indwelling at the end of biliary stent, 31 cases of duodenal papilla indwelling at the end of biliary stent, and 12 cases of horizontal portion of duodenum indwelling at the end of biliary stent. Incidence of fever within 2 weeks, perioperative mortality, 90-day obstruction rate, and median stent patency period were followed up and the results were analyzed.Results:The incidence of fever within 2 weeks of the three groups were significantly different [66.7% (12/18), 58.1% (18/31) and 16.7% (2/12), χ2=7.30, P=0.026]. There were no statistically differences in the perioperative mortality [0 (0/16), 3.2% (1/31) and 0 (0/10), χ2=1.09, P=1.000], 90-day obstruction rate [52.9% (9/17), 48.3% (14/29) and 40.0% (4/10), χ2=1.91, P=0.589], or median stent patency period (66.0 d, 91.5 d and 94.0 d, Z=4.96, P=0.084) among three groups. Conclusion:Patients with biliary plastic stents with ends placed at the horizontal portion of the duodenum show lower incidence of fever within two weeks after implantation, and similar median stent patency period, 90-day obstruction rate and perioperative mortality compared with intragastric indwelling and duodenal papilla indwelling groups. Therefore, biliary plastic stents with ends placed at the horizontal portion of the duodenum should be recommended as the preferred procedure.

Comparison of fully covered self-expanding metal stents and multiple plastic stents for benign biliary strictures / 中华消化内镜杂志

Objective:To compare the fully covered self-expanding metal stents (FCSEMS) and multiple plastic stents (MPS) in the effectiveness, safety and cost-effectiveness for benign bile duct strictures.Methods:A single-center retrospective study was conducted to analyze the clinical data of 107 patients with benign biliary strictures who underwent FCSEMS or MPS implantation through endoscopic retrograde cholangiopancreatography (ERCP) in Hangzhou First People's Hospital from January 2013 to June 2019.There were 54 cases in group FCSEMS and 53 cases in group MPS. Benign biliary stricture was confirmed by computed tomography (CT), magnetic resonance cholangiopancreatography (MRCP) and endoscopic ultrasonography. The primary index was the rate of stricture remission, and the secondary indices were the incidence of stricture recurrence, ERCP-related complications, the rate of stent migration, hospital stay and charges.Results:The median follow-up times were 10.0 (6.5, 18.0) months and 12.0 (9.0, 20.0) months in group FCSEMS and in group MPS respectively ( P>0.05). The rates of stricture remission in the two groups were 87.0% (47/54) and 83.0% (44/53), the incidences of stricture recurrence were 14.6% (6/41) and 23.5% (8/34), and the incidences of ERCP-related complications were 14.8% (8/54) and 11.9% (13/109), respectively. And the differences were not statistically significant (all P>0.05). But the stent migration rates of the two groups were 22.9% (11/54) and 2.8% (3/109) with significant difference ( P<0.001). Cost-effectiveness analysis showed that the median numbers of ERCP intervention in the two groups were 2 (2,2) times and 3 (2,4) times ( P<0.001), and the median hospital stays were 6.0 (4.0,11.0) days and 9.0 (6.5,16.0) days respectively ( P=0.009). The median hospitalization expenses of the two groups were 44 646 yuan and 51 355 yuan without significant difference ( P>0.05). Conclusion:The effectiveness, safety and cost of FCSEMS for benign bile duct stenosis are similar to those of MPS, but it reduces ERCP intervention and treatment cycles. Even with a certain migration rate, it can still be a first-line treatment approach.

Comprehensive minimally invasive treatment for biliary anastomotic stenosis after orthotopic liver transplantation: a single center analysis of 60 cases / 器官移植

Objective To evaluate the clinical efficacy of endoscopic retrograde cholangiopancreatography (ERCP)-based comprehensive minimally invasive treatment for biliary anastomotic stenosis (BAS) after liver transplantation. Methods Clinical data of 60 BAS recipients after liver transplantation were retrospectively analyzed, 54 male and 6 female, aged (48±10) years. ERCP was initially carried out. If it succeeded, plastic or metallic stents were placed into the biliary tract. If it failed, percutaneous transhepatic cholangial drainage (PTCD) or single-operator cholangioscopy (SpyGlass) was adopted to pass through the stenosis. If all these procedures failed, magnetic anastomosis or other special methods were delivered. The incidence and treatment of BAS after liver transplantation were summarized. The efficacy, stent removal and recurrence were observed. Results The median time of incidence of BAS after liver transplantation was 8 (4, 13) months. Within postoperative 1 year, 1-2 years and over 2 years, 39, 16 and 5 recipients were diagnosed with BAS, respectively. All 60 BAS recipients after liver transplantation were successfully treated, including 56 cases initially receiving ERCP, and 41 completing BAS treatment, with a success rate of 73%. The failure of guide wire was the main cause of ERCP failure. The success rates of PTCD, SpyGlass and magnetic anastomosis were 5/9, 5/7 and 7/8, respectively. Two recipients were successfully treated by percutaneous choledochoscope-assisted blunt guide wire technique and stent placement in the biliary and duodenal fistula. After 3 (3, 4) cycles of ERCP and 13 (8, 18) months of stent indwelling, 38 recipients reached the stent removal criteria, including 25 plastic stents and 13 metallic stents. The indwelling time of plastic stents was longer than that of metallic stents (P < 0.05). Six cases suffered from stenosis recurrence at 12 (8, 33) months after stent removal, and the recurrence rate was 16%. Six patients were treated with ERCP, and 5 of them did not recur after the stents were successfully removed. Multivariate analysis showed that delayed diagnosis of stenosis and frequent ERCP before stent removal were the independent risk factors for BAS recurrence (both P < 0.05). Conclusions ERCP-based comprehensive minimally invasive treatment may improve the success rate of BAS treatment after liver transplantation and yield satisfactory long-term efficacy. Delayed diagnosis of BAS and high frequent ERCP required for stent removal are the independent risk factors for BAS recurrence.

Stent-stone Complex Developed after Long-term Plastic Biliary Stent Placement / 대한췌담도학회지

Plastic biliary stents are commonly used during endoscopic retrograde cholangiopancreatography. Main indication for biliary stenting is benign or malignant obstruction. Plastic stents can be used as an escape route in patients with large common bile duct stones to provide drainage until definitive treatment. But, stent occlusion is the main disadvantage, limiting their patency to around 3 months, after which replacement is recommended. A biliary stent can act as a nidus for the biliary stone formation leading to stent-stone complex after long-term stent placement. This report was a case of a large stent-stone complex after plastic stent placement for 4 years. The stent-stone complex was successfully removed by mechanical lithotripsy and ballon catheter. In all other cases where plastic stents are placed into the common bile duct we should keep in mind that stents can act as nidus for stone formation, as all foreign bodies do.

A Comparative Study on the Efficacy of Covered Metal Stent and Plastic Stent in Unresectable Malignant Biliary Obstruction

BACKGROUND/AIMS: The placement of self expandable metal stent (SEMS) is one of the palliative therapeutic options for patients with unresectable malignant biliary obstruction. The aim of this study was to compare the effectiveness of a covered SEMS versus the conventional plastic stent. METHODS: We retrospectively evaluated 44 patients with unresectable malignant biliary obstruction who were treated with a covered SEMS (21 patients) or a plastic stent (10 Fr, 23 patients). We analyzed the technical success rate, functional success rate, early complications, late complications, stent patency and survival rate. RESULTS: There was one case in the covered SEMS group that had failed technically, but was corrected successfully using lasso. Functional success rates were 90.5% in the covered SEMS group and 91.3% in the plastic stent group. There was no difference in early complications between the two groups. Median patency of the stent was significantly prolonged in patients who had a covered SEMS (233.6 days) compared with those who had a plastic stent (94.6 days) (p=0.006). During the follow-up period, stent occlusion occurred in 11 patients of the covered SEMS group. Mean survival showed no significant difference between the two groups (covered SEMS group, 236.9 days; plastic stent group, 222.3 days; p=0.182). CONCLUSIONS: The patency of the covered SEMS was longer than that of the plastic stent and the lasso of the covered SEMS was available for repositioning of the stent.

Randomised Trial of Coil (EndocoilTM) Stent Versus Plastic Stent in Malignant Biliary Tract Obstruction / 대한소화기내시경학회지

BACKGROUND AND AIMS: Endoscopic stent placement has become accepted palliative therapy for malignant biliary tract obstruction (MBTO). The main problem of plastic stent are the clogging or migration. The new self expandable super-elastic metallic coil stent (Endo-coilTM, Instent Inc.) is claimed to allow large lumen and prolong biliary-stent patency. In a prospective randomised trial, we compared the efficacy and frequency of stent dysfunction of EndocoilTMand plastic stent (PercuflexR, Microvasive Co.). METHOD: Between Aug. 1994 and Mar. 1995, we assigned 29 patients (21 males and 8 females, mean age 63 years) with unresectable MBTO due to cancer of bile duct (17), pancreas (6) periampullary (3), gallbladder (2) and perichoedochal LN (1). Thirteen of patients under-went EndocoilTMstents (24 Fr) and other 16 patients underwent plastic stents (12 Fr) insertion via transpapillary route. Successful insertion of stents was attained all cases and no serious complication occured. RESULTS: All patients with EndocoilTM stents and 11 (68%) patients with plastic stents were relieved completely from jaundice (T. bilirubon <3.0 mg/dl). There was no differences in decreasement of bilirubin between two groups after 7 days and 30 days after stents insertion. Median patency of the stents was significantly prolonged in patients with EndocoilTM stents compared with those with plastic stents(205 days vs 92 days). The stent dysfunction was noted 2 cases (15%) in EndocoilTM due to tumor ingrowth. In contrast, stent dysfunction was occured in 10 cases (62%) of plastic stents due to clogging (7 cases) and migration (3 cases). The patients' overall median survival was not different significantly between two groups (EndocoilTM250 days vs plastic 196 days). CONCLUSIONS: Both ndocoilTMand plastic stents offer effective bile drainage in MBTO. However EndocoilTM stents may be more effective for providing longer periods of drainage due to lower frequency of stent dysfuction than plastic stents.

Comparative Evaluation of Various Biliary Stents in the Palliative Treatment of Malignant Biliary Obstruction / 대한내과학회지

OBJECTIVES: Endoscopic biliary drainage has been established as the palliative treatment of choice for malignant obstructive jaundice. At present, the major drawback of endoscopic biliary stenting is occlusion of the endoprosthesis with sludge, resulting in recurrence of jaundice or cholangitis. Recently, there are variable stents that have different materials, sizes, and designs have been used in efforts to overcome this problem. To determine the success rate of stent insertion, successful drainage rate, duration of patency, complications related to stent insertion, and cause of stent malfunction, plastic endoprosthesis compared to metal stents in palliative treatment of malignant biliary obstruction. METHOD: We retrospectively evaluated 157 patients (total number of stent insertion: 308 cases) with unresec table malignant biliary obstruction to receive either a plastic stent(group I, 261 cases) or metal stent(group II, 47 cases). The patients who were recieved plastic stent were subdivided to general plastic stents(group Ia, polyethylene, polyurethane, polyvinylchloride, 225 cases) and Tannenbaum stent(group Ib, Teflon, 36 times) group. And the patients who were received metal stent were subdivided to uncovered metal stents(group IIa, Gianturco R sch, Wall, Strecker, EndoCoil stent, 26 times) and membrane covered self-expandable metal stent(group IIb, 21 cases) group. RESULTS: 1) There were no statistical difference in successful rate of stent insertion and drainage effect of stent accord ing to the types of stent(p>0.05). 2) Median patency of the stent was significantly prolonged in patients with a metal stent(group II) com pared with those with a plastic stent(group I) (249 vs 123 days; p 0.05). 3) The rate of early complication related to stent insertion showed no significant difference in plastic and metal stent groups(P > 0.05). 4) Major causes of stent malfunction in plastic and metal stent were sludge(90% vs 21.4%), tumor ingrowth (4.4% vs 71.4%), and dislocation(5.6% vs 7.2%), respec tively. CONCLUSION: Metal stents have a longer patency than plastic stent in patients with malignant biliary obstruc tion. In plastic stents, Tannenbaum stents have a slighlty longer patency than other plastic stents, but there were no differences in the success rates, drainage effect and complication rates according to types of stents.

Treatment of Obstructed Nasolacrimal Duct by Lacrimal Stent without Fluoroscopic Guidance

This study was carried out to evaluate and investigate the clinical utility of the plastic nasolacrimal stents (Song's tube) without fluoroscopic guidance in treatment of the obstructed nasolacrimal duct. The anesthesia was performed with Tetra-caine contained epinephrine in the nasal mucosa, proparcaine in the conjunctival sac and 2% lidocaine for infratrochlear block. The plastic stent were placed in the lacrimal system with the head portion lying in the lacrimal sac and body in the nasolacrimal duct and projecting into the inferior meatus of the nasal cavity. Complete resolution of epiphora was accomplished in 92(97%) of the 95 eyes with mean follow up of 8.5 months (minimal 6 months, maximal 18 months), and there were no significant complications under this procedure. This noninvasive procedure was indicated the anatomic obstruction of the nasolacrimal system, especially obstruction was at the junction between the lacrimal sac and nasolacrimal duct or stenosis of the nasolacrimal duct, which can be the probing as possbile. The use of the plastic nasolacrimal stents without fluoroscopic guidance have many advantages, as follow; There are no surgical dacryocystorhinostomy procedure, simple surgical technique and short duration of procedure, no risk of exposure radiation, and no needs of fluoroscope instrument and radiologist. Although evaluation of a longer-term follow up will be needed to determine the effectiveness of this thechnique, the utility of the plastic nasolacrimal stents without fluoroscopic guidance seem to be of value in primary management of the obstructed nasolacrimal duct, prior to the dacryocystorhinostomy procedure in proper indication of the nasolacrimal duct obstruction.