Characteristics of fecal microbial communities in patients with non-anastomotic biliary strictures after liver transplantation

AIM To explore the possible relationship between fecal microbial communities and non-anastomotic stricture(NAS) after liver transplantation(LT).METHODS A total of 30 subjects including 10 patients with NAS, 10 patients with no complications after LT, and 10 nonLT healthy individuals were enrolled. Fecal microbial communities were assessed by the 16 S r RNA gene sequencing technology.RESULTS Different from the uncomplicated and healthy groups, unbalanced fecal bacterium ratio existed in patients with NAS after LT. The results showed that NAS patients were associated with a decrease of Firmicutes and Bacteroidetes and an increase of Proteobacteria at the phylum level, with the proportion-ratio imbalance between potential pathogenic families including Enterococcaceae, Streptococcaceae, Enterobacteriaceae, Pseudomonadaceae and dominant families including Bacteroidaceae. CONCLUSION The compositional shifts of the increase of potential pathogenic bacteria as well as the decrease of dominant bacteria might contribute to the incidence of NAS.

Diagnosis and Management of Biliary Strictures after Deceased-Donor Liver Transplantation Based on Clinical Practice

Biliary complications are still the main complications for liver transplantation recipients. Biliary strictures comprise the major part of all biliary complications after deceased-donor liver transplantation (LT). Biliary strictures following LT are divided into anastomotic strictures (AS) and non-anastomotic strictures (NAS). A Limitation of current published researches is that most studies aren’t based on clinical practice. The aim of this review is to summarize risk factors, clinical presentation, diagnosis and management in post-LT biliary strictures.

Novel magnetic compression technique for the treatment of postoperative anastomotic stenosis in rectal cancer:A case report

BACKGROUND The treatment of postoperative anastomotic stenosis after excision of rectal cancer is challenging.Endoscopic balloon dilation and radial incision are not effective in all patients.We present a new endoscopy-assisted magnetic compression technique(MCT)for the treatment of rectal anastomotic stenosis.We successfully applied this MCT to a patient who developed an anastomotic stricture after radical resection of rectal cancer.A 50-year-old man had undergone laparoscopic radical rectal cancer surgery at a local hospital 5 months ago.A colonoscopy performed 2 months ago indicated that the rectal anastomosis was narrow due to which ileostomy closure could not be performed.The patient came to the Magnetic Surgery Clinic of the First Affiliated Hospital of Xi'an Jiaotong University after learning that we had successfully treated patients with colorectal stenosis using MCT.We performed endoscopy-assisted magnetic compression surgery for rectal stenosis.The magnets were removed 16 d later.A follow-up colonoscopy performed after 4 months showed good anastomotic patency,following which,ileostomy closure surgery was performed.CONCLUSION MCT is a simple,non-invasive technique for the treatment of anastomotic stricture after radical resection of rectal cancer.The technique can be widely used in clinical settings.

Evaluation of the Quality of Micturition in Patients Who Underwent Anastomotic Urethroplasty at the Yaounde Central Hospital, Cameroon

Introduction: Radiological investigation which is the gold standard to perform following anastomotic urethroplasty in order to evaluate the quality of micturition is costly. In our context, due to financial limitations, reconstructive urologists prefer to use the uroflowmetry in order to assess the micturition post-surgery. Therefore, the objective of the study was to assess the quality of micturition using the uroflowmetry after anastomotic urethroplasty. Methodology: We conducted an 11-year retrospective review (1st January 2006-31st December 2017) and a cross-sectional descriptive observational study for a period of 8 months (November 2017-June 2018) at the Urology and Andrology Department of the Yaounde Central Hospital (YCH) of patients who were diagnosed with urethral stenosis and underwent an anastomotic urethroplasty at the YCH. We excluded patients who had incomplete files, patients lost to follow-up and did not do pre-operative uroflowmetry. Quality of micturition was evaluated using a uroflowmetry. Data was analyzed using EPI info 7.0. Parametric variables were reported as means and standard deviations and percentages and counts were used to report categorical variables. Results: We had a sample of 60 patients. The mean age was 42 ± 5 years with extremes ranging from 20 to 76 years. Twenty-seven (27) patients, or 45%, had no post-operative complications, and those who did had a urinary tract infection (26.70%). In our series, we had 82% excellent results (patient satisfied with his urination with bell-shaped urinary stream and urinary flow greater than or equal to 15 ml/sec);15% good results (patient with moderate dysuria with average urinary stream and urinary flow between 10 and 14.9 ml/sec) and 3% poor results (severe dysuria with urinary flow less than 10 ml/sec, urinary retention or urinary incontinence). Based on these results we can say that the success rate in our series was 97%. 96.70% of patients were satisfied against 3.3% who were not. Conclusion: Anastomotic urethroplasty is the gold standard for the treatment of short urethral strictures. The results are good in the immediate and long term post-operative period. The use of the uroflowmetry as a screening tool for evaluating the quality of micturition after urethroplasty is effective.

Anterior resection for rectal carcinoma-risk factors for anastomotic leaks and strictures

AIM:To determine the incidence and factors responsible for anastomotic leaks and stricture following anterior resection(AR)and its subsequent management.METHODS:Retrospective analysis of data from 108 patients with rectal carcinoma who underwent AR or low anterior resection(LAR)to identify the various preoperative,operative,and post operative factors that might have influence on anastomotic leaks and strictures.RESULTS:There were 68 males and 40 females with an average of 47 years(range 21-75 years).The median distance of the tumor from the anal verge was 8 cm(range 3-15 cm).Sixty(55.6%)patients underwent handsewn anastomosis and 48(44.4%)were stapled.The median operating time was 3.5 h(range2.0-7.5 h).Sixteen(14.6%)patients had an anastomotic leak.Among these,11 patients required reexploration and five were managed expectantly.The anastomotic leak rate was similar in patients with and without diverting stoma(8/60,13.4%with stoma and 8/48;16.7%without stoma).In 15(13.9%)patients,resection margins were positive for malignancy.Ninteen(17.6%)patients developed anastomotic strictures at a median duration of 8 mo(range 3-20 mo).Among these,15 patients were successfully managed with per-anal dilatation.On multivariate analysis,advance age(>60 years)was the only risk factor for anastomotic leak(P=0.004).On the other hand,anastomotic leak(P=0.00),mucin positive tumor(P =0.021),and lower rectal growth(P=0.011)were found as risk factors for the development of an anastomotic stricture.CONCLUSION:Advance age is a risk factor for an anastomotic leak.An anastomotic leak,a mucin-secreting tumor,and lower rectal growth predispose patients to develop anastomotic strictures.

Outcome of nephrostomy balloon dilation for vesicourethral anastomotic strictures following radical prostatectomy： a retrospective study

To evaluate the efficacy of nephrostomy balloon dilation （NBD） for patients who developed vesicourethral anastomotic stricture （VAS） following radical prostatectomy. NBD was performed in patients who developed VAS following radical prostatectomy. Quality of life （QoL）, International Prostate Symptom Score （IPSS） and maximal urinary flow rate （Qmax） were evaluated. Four hundred and sixty-three prostate cancer patients underwent radical retropubic prostatectomy （RRP）, and 86 underwent laparoscopic radical prostatectomy （LRP）. Most patients （90.3%） had T2 or T3 prostate cancer and a pathological Gleason score of ; 7. Forty-five （8.2%） and four （4.7%） patients developed VAS due to radical or LRP, respectively. Forty （89%） patients underwent NBD, including three cases of repeat dilation. The median Qmax was 4 ml s- （interquartile range （IQR）, 2.3-5.6） before dilation and improved to 16 ml s- （IQR, 15-19） and 19 ml s-1 （IQR, 18-21） at the 1- and 12-month follow-up, respectively （P〈 0.01）. Fifteen （37.5%） patients had urinary incontinence prior to dilation, whereas only three （7.5%） patients had incontinence 12 months following dilation （P 〈 0.01）. The median IPSS score improved from 19 （IQR, 17-24） before dilation to 7 （IQR, 6-8） at 12 months following dilation, and the QoL score improved from 5 （IQR, 4-6） before dilation to 2 （IQR, 2-3） at 12 months following dilation （P 〈 0.01 in both）. VAS occurs in a small but significant proportion of patients following radical prostatectomy. NBD offers an effective remedy for VAS.

Fecal marker levels as predictors of need for endoscopic balloon dilation in Crohn's disease patients with anastomotic strictures

AIM To evaluate the accuracy and best cut-off value of fecal calprotectin(FC) and fecal lactoferrin(FL) to predict disease recurrence in asymptomatic patients presenting with anastomotic strictures. METHODS This was a longitudinal single tertiary center study based on prospectively collected data(recorded in a clinical database created for this purpose) performed between March 2010 and November 2014. Crohn's disease(CD) patients with anastomotic stricture who submitted to postoperative endoscopic evaluation were included. Stools were collected on the day before bowel cleaning for FC and FL. Endoscopic balloon dilation(EBD) was performed if the patient presented an anastomotic stricture not traversed by the colonoscope, regardless of patients' symptoms. Successful dilation was defined as passage of the colonoscope through the dilated stricture into the neotermimal ileum.Postoperative recurrence was defined as a modified Rutgeerts score of ≥ i2 b. RESULTS In a total of 178 patients who underwent colonoscopy, 58 presented an anastomotic stricture, 86% were asymptomatic, and 48(54% male; median age of 46.5 years) were successfully dilated. Immediate success rate was 92% and no complications were recorded. FC and FL levels correlated significantly with endoscopic recurrence(P < 0.001) with an optimal cut-off value of 90.85 μg/g(sensitivity of 95.5%, specificity of 69.2%, positive predictive value(PPV) of 72.4%, negative predictive value(NPV) of 94.7% and accuracy of 81%] for FC and of 5.6 μg/g(sensitivity of 77.3%, specificity of 69.2%, PPV of 68%, NPV of 78.4% and accuracy of 72.9%) for FL.CONCLUSION Fecal markers are good predictors of CD endoscopic recurrence in patients with asymptomatic anastomotic stricture. FC and FL may guide the need for EBD in this context.

Short benign ileocolonic anastomotic strictures-management with bi-flanged metal stents:Six case reports and review of literature

BACKGROUND The endoscopic management of benign short post-anastomotic ileocolonic stricture(PAICS) that is refractory to primary and secondary treatment modalities remains challenging.The lumen-apposing metal stent(LAMS) is a novel device recently developed for therapeutic gastrointestinal endoscopy.LAMSs have demonstrated significantly better results with regard to stent migration than fully covered self-expandable metal stents(FCSEMSs).CASE SUMMARY This article presents six cases of symptomatic PAICS successfully treated with a LAMS and a review of the relevant literature.We report a life-saving technique not previously documented and the use of technology to improve patient outcomes.The six patients(median age,75 years) suffered from vomiting,constipation and recurrent abdominal pain,with symptoms starting 23-25 wk post-surgery.The median stricture length was 1.83 cm.All six patients underwent successful and uneventful bi-flanged metal stent(BFMS)-LAMS placement for benign PAICS.All patients remained asymptomatic during the three months of stent indwelling and up to a median of 7 mo after stent removal.According to the literature,the application of LAMS for PAICS is associated with a < 10% risk of migration and a < 5% risk of bleeding.Conversely,FCSEMS has a high migration rate(15%-50%).CONCLUSION The evolving role of interventional endoscopy and the availability of LAMSs provide patients with minimally invasive treatment options,allowing them to avoid more invasive surgical interventions.The BFMS(NAGI stent) is longer and larger than the prototype AXIOS-LAMS,which should be considered in the management of short ileocolonic post-anastomotic strictures longer than 10 mm and shorter than 30 mm.

Percutaneous interventional therapy for anastomotic biliary strictures after orthotopic liver transplantation

Objective To describe the technique,efficacy, and safety of percutaneous interventional therapy for anastomotic biliary strictures after orthotopic liver transplantation ( OLT) . Methods From May 2004 to December 2009,25 patients with anastomotic biliary stric-

Paclitaxel-eluting balloon dilation of biliary anastomotic stricture after liver transplantation

AIM:To investigate the safety and effectiveness of endoscopic therapy with a paclitaxel-eluting balloon(PEB) for biliary anastomotic stricture(AS) after liver transplantation(LT).METHODS:This prospective pilot study enrolled 13 consecutive eligible patients treated for symptomatic AS after LT at the University Hospital of Münster between January 2011 and March 2014.The patients were treated by endoscopic therapy with a PEB and followed up every 8 wk by endoscopic retrograde cholangiopancreatography(ERCP).In cases of re-stenosis,further balloon dilation with a PEB was performed.Follow-up was continued until 24 mo after the last intervention.RESULTS:Initial technical feasibility,defined as successful balloon dilation with a PEB during the initial ERCP procedure,was achieved in 100% of cases.Long-term clinical success(LTCS),defined as no need for further endoscopic intervention for at least 24 mo,was achieved in 12 of the 13 patients(92.3%).The mean number of endoscopic interventions required to achieve LTCS was only 1.7 ± 1.1.Treatment failure,defined as the need for definitive alternative treatment,occurred in only one patient,who developed recurrent stenosis with increasing bile duct dilatation that required stent placement.CONCLUSION:Endoscopic therapy with a PEB is very effective for the treatment of AS after LT,and seems to significantly shorten the overall duration of endoscopic treatment by reducing the number of interventions needed to achieve LTCS.

Bilioenteric anastomotic stricture in patients with benign and malignant tumors: prevalence,risk factors and treatment

BACKGROUND: Stricture formation at the bilioenteric anastomosis is a rare but important postoperative complication. However, information on this complication is lacking in the literature. In the present study, we aimed to assess its prevalence and predictive factors, and report our experience in managing bilioenteric anastomotic strictures over a ten-year period. METHODS: A total of 420 patients who had undergone bilioenteric anastomosis due to benign or malignant tumors between February 2001 and December 2011 were retrospectively reviewed. Univariate and multivariate modalities were used to identify predictive factors for anastomotic stricture occurrence. Furthermore, the treatment of anastomotic stricture was analyzed. RESULTS: Twenty-one patients (5.0%) were diagnosed with bilioenteric anastomotic stricture. There were 12 males and 9 females with a mean age of 61.6 years. The median time after operation to anastomotic stricture was 13.6 months (range, 1 month to 5 years). Multivariate analysis identified that surgeon volume (<30 cases) (odds ratio:-1.860; P=0.044) was associated with the anastomotic stricture while bile duct size (>6 mm) (odds ratio: 2.871; P=0.0002) had a negative association. Balloon dilation was performed in 18 patients, biliary stenting in 6 patients, and reoperation in 4 patients. Five patients died of tumor recurrence, and one of heart disease. CONCLUSIONS: Bilioenteric anastomotic stricture is an uncommon complication that can be treated primarily by interventional procedures. Bilioenteric anastomosis may be performed by a surgeon in his earlier training period under the guidance of an experienced surgeon. Bile duct size >6 mm may play a protective role.

Dilation of a severe bilioenteric or pancreatoenteric anastomotic stricture using a Soehendra Stent Retriever

Bilioenteric or pancreatoenteric anastomotic stric-tures often occur after surgery for a pancreaticobiliary disorder. Therapeutic endoscopic retrograde cholan-giopancreatography using balloon enteroscopy has been shown to be feasible and effective in patients with such strictures. However, when a benign anas-tomotic stricture is severe, a dilation catheter cannot pass through the stricture despite successful insertion of the guidewire. We report on the usefulness of the Soehendra Stent Retriever over a guidewire for dilating a severe bilioenteric or pancreatoenteric anastomotic stricture under short double-balloon enteroscopy, in two patients with surgically altered anatomies.

Outcomes of side-to-side conversion hepaticojejunostomy for biliary anastomotic stricture after right-liver living donor liver transplantation

BACKGROUND:Conversion hepaticojejunostomy is considered the salvage intervention for biliary anastomotic stricture,a common complication of right-liver living donor liver transplantation with duct-to-duct anastomosis,after failed endoscopic treatment.The aim of this study is to compare the outcomes of side-to-side hepaticojejunostomy with those of endto-side hepaticojejunostomy.METHODS:Prospectively collected data of 402 adult patients who had undergone right-liver living donor liver transplantation with duct-to-duct anastomosis were reviewed.Diagnosis of biliary anastomotic stricture was made based on clinical,biochemical,histological and radiological results.Endoscopic treatment was the first-line treatment of biliary anastomotic stricture.RESULTS:Interventional radiological or endoscopic treatment failed to correct the biliary anastomotic stricture in 13 patients,so they underwent conversion hepaticojejunostomy.Ten of them received end-to-side hepaticojejunostomy and three received side-to-side hepaticojejunostomy.In the end-to-side group,two patients sustained hepatic artery injury requiring repeated microvascular anastomosis,two developed restenosis requiring further percutaneous transhepatic biliary drainage and balloon dilatation,and two required revision hepaticojejunostomy.In the side-to-side group,one patient developed re-stenosis requiring further endoscopic retrograde cholangiography and balloon dilatation.No re-operation was needed in this group.Otherwise,outcomes in the two groups were similar in terms of liver function and graft survival.CONCLUSIONS:Despite the similar outcomes,side-to-side hepaticojejunostomy may be a better option for bile duct reconstruction after failed interventional radiological or endoscopic treatment because it can decrease the chance of hepatic artery injury and allows future endoscopic treatment if re-stricture develops.However,more large-scale studies are warranted to validate the results.

Off label use of lumen-apposing metal stent for persistent gastro-jejunal anastomotic stricture

We are reporting a novel "off-label" use of lumen apposing metal stent(LAMS) for management of refractory gastro-jejunal(GJ) anastomotic stricture after Roux-en-y gastric bypass(RYGB). With increasing prevalence of obesity, bariatric surgery is performed more frequently than ever. RYGB is one of the most commonly performed bariatric procedures. GJ anastomotic stricture is a late complication of this procedure. Our patient, seven years after RYGB developed GJ anastomotic ulcer and subsequently a stricture not amendable to repeated pneumatic dilations. Instead of using the conventional fully covered self-expanding metal stent(fc SEMS) we deployed the relatively new LAMS keeping in mind its novel dumbbell shaped design. Our patient's symptoms were controlled successfully and she remained asymptomatic on follow-up. Despite initial approval for pancreatic pseudocyst drainage, LAMS has been used with increased frequency at various locations within gastrointestinal tract including GJ anastomotic strictures. Future randomized control trials are warranted to compare the efficacy of fcSEMS to LAMS.

在 colorectal 外科的 Non-steroidal 反煽动性的药: 为 anastomotic 复杂并发症的一个风险因素？

In a recent article, Gorissen et al report on 795 patients with primary colorectal anastomosis operated on during the period 2008-2010 for different colorectal conditions at two centres. The leakage rate was significantly higher among patients who were administered non-steroidal anti-inflammatory drugs (NSAIDs) in the perioperative course. A dose-response relationship could also be traced, where longer NSAID use yielded a higher risk of anastomotic breakdown. However, as this study is observational in design, confounding by indication may be present and there is also a risk of residual confounding from unmeasured covariates. Moreover, the question whether different affinity for the cyclooxygenase enzyme is important in different NSAIDs seems to be largely unanswered. The results, conclusions and clinical relevance of the aforementioned study, including the possible effects of different types of NSAIDs, are discussed. While acknowledging that this study represents the best attempt so far in establishing the causal relationship between perioperative NSAID use and anastomotic leakage, the need for further research in this important area is underlined.

Endoscopic incisional therapy for benign esophageal strictures: Technique and results

Benign esophageal strictures refractory to the conventional balloon or bougie dilatation may be subjected to various adjunctive modes of therapy, one of them being endoscopic incisional therapy(EIT). A proper delineation of the stricture anatomy is a prerequisite. A host of electrocautery and mechanical devices may be used, the most common being the use of needle knife, either standard or insulated tip. The technique entails radial incision and cutting off of the stenotic rim. Adjunctive therapies, to prevent re-stenosis, such as balloon dilatation, oral or intralesional steroids or argon plasma coagulation can be used. The common strictures where EIT has been successfully used are Schatzki's rings(SR) and anastomotic strictures(AS). Short segment strictures(< 1 cm) have been found to have the best outcome. When compared with routine balloon dilatation, EIT has equivalent results in treatment na?ve cases but better long term outcome in refractory cases. Anecdotal reports of its use in other types of strictures have been noted. Post procedure complications of EIT are mild and comparable to dilatation therapy. As of the current evidence, incisional therapy can be used for management of refractory AS and SR with relatively short stenosis(< 1 cm) with good safety profile and acceptable long term patency.

Biliary complications in liver transplantation: Impact of anastomotic technique and ischemic time on short- and long-term outcome

AIM: To elucidate the impact of various donor recipient and transplant factors on the development of biliary complications after liver transplantation.METHODS: We retrospectively reviewed 200 patients of our newly established liver transplantation(LT) program, who received full size liver graft. Biliary reconstruction was performed by side-to-side(SS), end-to-end(EE) anastomosis or hepeaticojejunostomy(HJ). Biliary complications(BC), anastomotic stenosis, bile leak, papillary stenosis, biliary drain complication, ischemic type biliary lesion(ITBL) were evaluated by studying patient records, corresponding radiologic imaging and reports of interventional procedures [e.g., endoscopic retrograde cholangiopancreatography(ERCP)]. Laboratory results included alanine aminotransferase(ALT), gammaglutamyltransferase and direct/indirect bilirubin with focus on the first and fifth postoperative day, six weeks after LT. The routinely employed external bile drain was examined by a routine cholangiography on the fifth postoperative day and six weeks after transplantation as a standard procedure, but also whenever clinically indicated. If necessary, interventional(e.g., ERCP) or surgical therapy was performed. In case of biliary complication, patients were selected, assigned to different complication-groups and subsequently reviewed in detail. To evaluate the patients outcome, we focussed on appearance of postoperative/post-interventional cholangitis, need for rehospitalisation, retransplantation, ITBL or death caused by BC.RESULTS: A total of 200 patients [age: 56(19-72), alcoholic cirrhosis: n = 64(32%), hepatocellular carcinoma: n = 40(20%), acute liver failure: n = 23(11.5%), cryptogenic cirrhosis: n = 22(11%), hepatitis B virus /hepatitis C virus cirrhosis: n = 13(6.5%), primary sclerosing cholangitis: n = 13(6.5%), others: n = 25(12.5%) were included. The median follow-up was 27 mo until June 2015. The overall biliary complication rate was 37.5%(n = 75) with anastomotic strictures(AS): n = 38(19%), bile leak(BL): n = 12(6%), biliary drain complication: n = 12(6%); papillary stenosis(PS): n = 7(3.5%), ITBL: n = 6(3%). Clinically relevant were only 19%(n = 38). We established a comprehensive classification for AS with four grades according to clinical relevance. The reconstruction techniques [SS: n = 164, EE: n = 18, HJ: n = 18] showed no significant impact on the development of BCs in general(all n < 0.05), whereas in the HJ group significantly less AS were found(P = 0.031). The length of donor intensive care unit stay over 6 d had a significant influence on BC development(P = 0.007, HR = 2.85; 95%CI: 1.33-6.08) in the binary logistic regression model, whereas other reviewed variables had not [warm ischemic time > 45 min(P = 0.543), cold ischemic time > 10 h(P = 0.114), ALT init > 1500 U/L(P = 0.631), bilirubin init > 5 mg/d L(P = 0.595), donor age > 65(P = 0.244), donor sex(P = 0.068), rescue organ(P = 0.971)]. 13%(n = 10) of BCs had no therapeutic consequences, 36%(n = 27) resulted in repeated lab control, 40%(n = 30) received ERCP and 11%(n = 8) surgical therapy. Fifteen(7.5%) patients developed cholangitis [AS(n = 6), ITBL(n = 5), PS(n = 3), biliary lesion BL(n = 1)]. One patient developed ITBL twelve months after LT and subsequently needed retransplantation. Rehospitalisation rate was 10.5 %(n = 21) [AS(n = 11), ITBL(n = 5), PS(n = 3), BL(n = 1)] with intervention or reinterventional therapy as main reasons. Retransplantation was performed in 5(2.5%) patients [ITBL(n = 1), acute liver injury(ALI) by organ rejection(n = 3), ALI by occlusion of hepatic artery(n = 1)]. In total 21(10.5%) patients died within the follow-up period. Out of these, one patient with AS developed severe fatal chologenic sepsis after ERCP.CONCLUSION: In our data biliary reconstruction technique and ischemic times seem to have little impact on the development of BCs.

Short and long-term outcomes of endoscopic balloon dilatation for Crohn's disease strictures

AIM:To investigate the short and long-term outcomes of endoscopic balloon dilatation(EBD) for Crohn's disease(CD) strictures.METHODS:Between January 1995 and December 2011,47 EBD procedures were performed in 30 patients(8 females and 22 males) with CD.All patients had strictures through which an endoscope could not pass,and symptoms of these strictures included abdominal pain,abdominal fullness,nausea,and/or vomiting.The 47 strictures included 17 anastomotic and 30 de novo strictures.Endoscopy and dilatation were performed under conscious sedation with intravenous diazepam or flunitrazepam.The dilatations were all performed using through-the-scope balloons with diameters from 8 mm to 20 mm on inflation and lengths of 30-80 mm.Each dilatation session consisted of two to four,3-min multistep inflations of the balloon,repeated at intervals of 1 wk until adequate dilatation(up to 15-20 mm in diameter) was achieved.The follow-up data were collected from medical records and analyzed retrospectively.Primary success was defined as passage of the scope through the stricture after EBD.Longterm outcomes were analyzed focusing on interventionfree survival and surgery-free survival demonstrated by the Kaplan-Meier method.(Intervention-free meant cases in which neither endoscopic balloon re-dilatation nor surgery was needed after the first dilatation during the observation period).The log rank test was used to evaluate the difference in long-term outcomes between anastomotic and de novo stricture cases.RESULTS:Primary success was achieved in 44 of the 47 strictures(93.6%).Balloon dilatations failed in 3 cases(6.4%).In 1 case,EBD was a technical failure because the guide-wire could not be passed through the stricture which showed severe adhesion and was a flexural lesion of the intestine.In 2 cases,unexpected perforations occurred immediately after balloon dilatation.Of the 47 treatments,complications occurred in 5(10.6%).All 5 patients had de novo strictures.One suffered bleeding,two high fever and there were colorectal perforations.One of the patients with a colorectal perforation was treated surgically,the other was managed conservatively.These 2 cases correspond to the two aforementioned EBD failures.Long-term outcomes were evaluated for the 44 successfully-treated strictures after a median follow-up of 26 mo(range,2-172 mo).During the observation period,re-strictures after EBDs occurred in 26 cases(60.5%).Fourteen of these 26 re-stricture cases underwent EBD again,but in two EBD failed and surgery was ultimately performed in both cases.Twelve of the 26 re-stricture cases were initially treated surgically when the re-strictures occurred.Finally,30 of the 47 strictures(63.8%) were successfully managed with EBD,allowing surgery to be avoided.Intervention-free survival evaluated by the Kaplan-Meier method was 75% at 12 mo,58% at 24 mo,and 43% at 36 mo.There was no significant difference between the anastomotic strictures(n = 16) and de novo strictures(n = 28) in the intervention-free survival as evaluated by the log-rank test.Surgery-free survival evaluated by the Kaplan-Meier method was 90% at 12 mo,75% at 24 mo,and 53% at 36 mo.The 16 anastomotic strictures were associated with significantly better surgery-free survivals than the 28 de novo strictures(log-rank test:P < 0.05).CONCLUSION:Anastomotic strictures were associated with better long-term outcomes than de novo strictures,indicating that stricture type might be useful for predicting the long-term outcomes of EBD.

Endoscopic therapy of benign biliary strictures

Benign biliary strictures are being increasingly treated with endoscopic techniques. The benign nature of the stricture should be first confirmed in order to ensure appropriate therapy. Surgery has been the traditional treatment, but there is increasing desire for minimally invasive endoscopic therapy. At present, endoscopy has become the first line approach for the therapy of post- liver transplant anastomotic strictures and distal (Bismuth Ⅰand Ⅱ) post-operative strictures. Strictures related to chronic pancreatitis have proven more difficult to treat, and endoscopic therapy is reserved for patients who are not surgical candidates. The preferred endoscopic approach is aggressive treatment with gradual dilation of the stricture and insertion of multiple plastic stents. The use of uncovered self expandable metal stents should be discouraged due to poor long-term results. Treatment with covered metal stents or bioabsorbable stents warrants further evaluation. This area of therapeutic endoscopy provides an ongoing opportunity for fresh research and innovation.

Endoscopic management of biliary strictures after liver transplantation

Bile duct strictures remain a major source of morbidity after orthotopic liver transplantation (OLT). Biliary strictures are classifi ed as anastomotic or non-anastomotic strictures according to location and are defi ned by distinct clinical behaviors. Anastomotic strictures are localized and short. The outcome of endoscopic treatment for anastomotic strictures is excellent. Nonanastomotic strictures often result from ischemic and immunological events, occur earlier and are usually multiple and longer. They are characterized by a far less favorable response to endoscopic management, higher recurrence rates, graft loss and need for retransplantation. Living donor OLT patients present a unique set of challenges arising from technical factors, and stricture risk for both recipients and donors. Endoscopic treatment of living donor OLT patients is less promising. Current endoscopic strategies for biliary strictures after OLT include repeated balloon dilations and placement of multiple side-by-side plastic stents. Lifelong surveillance is required in all types of strictures. Despite improvements in incidence and long term outcomes with endoscopic management, and a reduced need for surgical treatment, the impact of strictures on patients after OLT is signifi cant. Future considerations include new endoscopic technologies and improved stents, which could potentially allow for a decreased number of interventions, increased intervals before retreatment, and decreased reliance on percutaneous and surgical modalities. This review focuses on the role of endoscopy in biliary strictures, one of the most common biliary complications after OLT.