Still elusive: Developments in the accurate diagnosis of indeterminate biliary strictures

Indeterminate biliary strictures pose a significant diagnostic dilemma for gastroenterologists.Despite advances in endoscopic techniques and instruments,it is difficult to differentiate between benign and malignant pathology.A positive histological diagnosis is always preferred prior to high risk hepatobiliary surgery,or to inform other types of therapy.Endoscopic retrograde cholangiopancreato-graphy with brushings has low sensitivity and despite significant improvements in instruments there is still an unacceptably high false negative rate.Other methods such as endoscopic ultrasound and cholangioscopy have improved diagnostic quality.In this review we explore the techniques available to aid accurate diagnosis of indeterminate biliary strictures and obtain accurate histology to facilitate clinical management.

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.

Clinical approach to indeterminate biliary strictures:Clinical presentation,diagnosis,and workup

Despite advances in cross-sectional imaging and endoscopic technology,bile duct strictures remain a challenging clinical entity.It is crucial to make an early determination of benign or malignant nature of biliary strictures.Early diagnosis not only helps with further management but also minimizes mortality and morbidity associated with delayed diagnosis.Conventional imaging and endoscopic techniques,particularly endoscopic retrograde cholangiopancreatography(ERCP)and tissue sampling techniques play a key in establishing a diagnosis.Indeterminate biliary strictures(IDBSs)have no definite mass on imaging or absolute histopathological diagnosis and often warrant utilization of multiple diagnostics to ascertain an etiology.In this review,we discuss possible etiologies,clinical presentation,diagnosis,and management of IDBSs.Based on available data and expert opinion,we depict an evidence based diagnostic algorithm for management of IDBSs.Areas of focus include use of traditional tissue sampling techniques such as ERCP with brush cytology,intraductal biopsies,fluorescence in situ hybridization and flow cytometry.We also describe the role of endoscopic ultrasound(EUS)-guided fine needle aspiration and biopsies,cholangioscopy,confocal laser endomicroscopy,and intraductal EUS in management of IDBSs.

Endoscopic management of benign biliary strictures:Looking for the best stent to place

Benign biliary strictures(BBS)might occur due to different pancreaticobiliary conditions.The etiology and location of biliary strictures are responsible of a wide array of clinical manifestations.The endoscopic approach endoscopic retrograde cholangiopancreatography represents the first-line treatment for BBS,considering interventional radiology and surgery when endoscopic treatment fails or it is not suitable.The purpose of this review is to provide an overview of possible endoscopic treatments for the optimal management of this subset of patients.

Minimally invasive surgery for post cholecystectomy biliary stricture:current evidence and future perspectives

Postcholecystectomy bile duct injury(BDI)remains a devastating iatrogenic complication that adversely impacts the quality of life with high healthcare costs.Despite a decrease in the incidence of laparoscopic cholecystectomy-related BDI,the absolute number remains high as cholecystectomy is a commonly performed surgical procedure.Open Roux-en-Y hepaticojejunostomy with meticulous surgical technique remains the gold standard surgical procedure with excellent longterm results in most patients.As with many hepatobiliary disorders,a minimally invasive approach has been recently explored to minimize access-related complications and improve postoperative recovery.Since patients with gallstone disease are often admitted for a minimally invasive cholecystectomy,laparoscopic and robotic approaches for repairing postcholecystectomy biliary stricture are attractive.While recent series have shown the feasibility and safety of minimally invasive post-cholecystectomy biliary stricture management,most are retrospective analyses with small sample sizes.Also,long-term follow-up is avail-able only in a limited number of studies.The principles and technique of minimally invasive repair resemble open repair except for the extent of adhesiolysis and the suturing technique with continuous sutures commonly used in minimally invasive approaches.The robotic approach overcomes key limitations of laparoscopic surgery and has the potential to become the preferred minimally invasive approach for the repair of postcholecystectomy biliary stricture.Despite increasing use,lack of prospective studies and selection bias with available evidence precludes definitive conclusions regarding minimally invasive surgery for managing postcholecystectomy biliary stricture.High-volume prospective studies are required to confirm the initial promising outcomes with minimally invasive surgery.

Current diagnosis and treatment of benign biliary stricturesafter living donor liver transplantation

Despite advances in surgical techniques, benign biliary strictures after living donor liver transplantation(LDLT) remain a significant biliary complication and play an important role in graft and patient survival. Benign biliary strictures after transplantation are classified into anastomotic or non-anastomotic strictures. These two types differ in presentation, outcome, and response to therapy. The leading causes of biliary strictures include impaired blood supply, technical errors during surgery, and biliary anomalies. Because patients usually have non-specific symptoms, a high index of suspicion should be maintained. Magnetic resonance cholangiography has gained widespread acceptance as a reliable noninvasive tool for detecting biliary complications. Endoscopy has played an increasingly prominent role in the diagnosis and treatment of biliary strictures after LDLT. Endoscopic management in LDLT recipients may be more challenging than in deceased donor liver transplantation patients because of the complex nature of the duct-to-duct reconstruction. Repeated aggressive endoscopic treatment with dilation and the placement of multiple plastic stents is considered the first-line treatment for biliary strictures. Percutaneous and surgical treatments are now reserved for patients for whom endoscopic management fails and for those with multiple, inaccessible intrahepatic strictures or Roux-en-Y anastomoses. Recent advances in enteroscopy enable treatment, even in these latter cases. Direct cholangioscopy, another advanced form of endoscopy, allows direct visualization of the inner wall of the biliary tree and is expected to facilitate stenting or stone extraction. Rendezvous techniques can be a good option when the endoscopic approach to the biliary stricture is unfeasible. These developments have resulted in almost all patients being managed by the endoscopic approach.

Biliary strictures complicating living donor liver transplantation:Problems,novel insights and solutions

Biliary stricture complicating living donor liver transplantation(LDLT) is a relatively common complication, occurring in most transplant centres across the world. Cases of biliary strictures are more common in LDLT than in deceased donor liver transplantation. Endoscopic management is the mainstay for biliary strictures complicating LDLT and includes endoscopic retrograde cholangiography, sphincterotomy and stent placement(with or without balloon dilatation). The efficacy and safety profiles as well as outcomes of endoscopic management of biliary strictures complicating LDLT is an area that needs to be viewed in isolation, owing to its unique set of problems and attending complications; as such, it merits a tailored approach, which is yet to be well established. The diagnostic criteria applied to these strictures are not uniform and are over-reliant on imaging studies showing an anastomotic narrowing. It has to be kept in mind that in the setting of LDLT, a subjective anastomotic narrowing is present in most cases due to a mismatch in ductal diameters. However, whether this narrowing results in a functionally significant narrowing is a question that needs further study. In addition, wide variation in the endotherapy protocols practised in most centres makes it difficult to interpret the results and hampers our understanding of this topic. The outcome definition for endotherapy is also heterogenous and needs to be standardised to allow for comparison of data in this regard and establish a clinical practice guideline. There have been multiple studies in this area in the last 2 years, with novel findings that have provided solutions to some of these issues. This review endeavours to incorporate these new findings into the wider understanding of endotherapy for biliary strictures complicating LDLT, with specific emphasis on diagnosis of strictures in the LDLT setting, endotherapy protocols and outcome definitions. An attempt is made to present the best management options currently available as well as directions for future research in the area.

Biliary drainage strategy of unresectable malignant hilar strictures by computed tomography volumetry

AIM:To identify criteria for predicting successful drainage of unresectable malignant hilar biliary strictures(UMHBS) because no ideal strategy currently exists.METHODS:We examined 78 patients with UMHBS who underwent biliary drainage.Drainage was considered effective when the serum bilirubin level decreased by ≥ 50% from the value before stent placement within 2 wk after drainage, without additional intervention.Complications that occurred within 7 d after stent placement were considered as early complications.Before drainage, the liver volume of each section(lateral and medial sections of the left liver and anterior and posterior sections of the right liver) was measured using computed tomography(CT) volumetry.Drained liver volume was calculated based on the volume of each liver section and the type of bile duct stricture(according to the Bismuth classification).Tumor volume, which was calculated by using CT volumetry, was excluded from the volume of each section.Receiver operating characteristic(ROC) analysis was performed to identify the optimal cutoff values for drained liver volume.In addition, factors associated with the effectiveness of drainage and early complications were evaluated.RESULTS:Multivariate analysis showed that drained liver volume [odds ratio(OR) = 2.92, 95%CI:1.648-5.197; P < 0.001] and impaired liver function(with decompensated liver cirrhosis)(OR = 0.06, 95%CI:0.009-0.426; P = 0.005) were independent factors contributing to the effectiveness of drainage.ROC analysis for effective drainage showed cutoff values of 33% of liver volume for patients with preserved liver function(with normal liver or compensated livercirrhosis)and 50%for patients with impaired liver function(with decompensated liver cirrhosis).The sensitivity and specificity of these cutoff values were82%and 80%for preserved liver function,and 100%and 67%for impaired liver function,respectively.Among patients who met these criteria,the rate of effective drainage among those with preserved liver function and impaired liver function was 90%and 80%,respectively.The rates of effective drainage in both groups were significantly higher than in those who did not fulfill these criteria(P<0.001 and P=0.02,respectively).Drainage-associated cholangitis occurred in 9 patients(12%).A smaller drained liver volume was associated with drainage-associated cholangitis(P<0.01).CONCLUSION:Liver volume drainage≥33%in patients with preserved liver function and≥50%in patients with impaired liver function correlates with effective biliary drainage in UMHBS.

Diagnosis of biliary strictures after liver transplantation:Which is the best tool?

AIM: To evaluate the diagnostic value of different indirect methods like biochemical parameters, ultrasound (US) analysis, CT-scan and MRI/MRCP in comparison with endoscopic retrograde cholangiography (ERC), for diagnosis of biliary complications after liver transplantation. METHODS: In 75 patients after liver transplantation, who received ERC due to suspected biliary complications, the result of the cholangiography was compared to the results of indirect imaging methods performed prior to ERC. The cholangiography showed no biliary stenosis (NoST) in 25 patients, AST in 27 and ITBL in 23 patients. RESULTS: Biliary congestion as a result of AST was detected with a sensitivity of 68.4% in US analysis (specificity 91%), of 71% in MRI (specificity 25%) and of 40% in CT (specificity 57.1%). In ITBL, biliary congestion was detected with a sensitivity of 58.8% in the US, 88.9%in MRI and of 83.3% in CT. However, as anastomotic or ischemic stenoses were the underlying cause of biliary congestion, the sensitivity of detection was very low. InMRI detected the dominant stenosis at a correct localization in 22% and CT in 10%, while US failed completely. The biochemical parameters, showed no significant difference in bilirubin (median 5.7; 4,1; 2.5 mg/dL), alkaline phosphatase (median 360; 339; 527 U/L) or gamma glutamyl transferase (median 277; 220; 239 U/L) levels between NoST, AST and ITBL.CONCLUSION: Our data confirm that indirect imaging methods to date cannot replace direct cholangiography for diagnosis of post transplant biliary stenoses. However MRI may have the potential to complement or precede imaging by cholangiography. Optimized MRCP-processing might further improve the diagnostic impact of this method.

Evaluation of fully covered self-expanding metal stents in benign biliary strictures and bile leaks

AIM: To investigate the use of fully covered metal stents in benign biliary strictures (BBS) and bile leaks. METHODS: We studied 17 patients, at Harbor-UCLA Medical center (Los Angeles), with BBS (n=12) and bile leaks (n=5) from July 2007 to February 2012 that had received placement of fully covered self-expanding metal stents (FCSEMs). Fourteen patients had endoscopic placement of VIABIL (Conmed, Utica, New York, United States) stents and three had Wallflex (Boston Scientific, Mass) stents. FCSEMS were 8 mm or 10 mm in diameter and 4 cm to 10 cm in length. Patients were followed at regular intervals to evaluate for symptoms and liver function tests. FCSEMS were removed after 4 or more weeks. Resolution of BBS and leak was documented cholangiographically following stent removal. Stent patency can be defined as adequate bile and contrast flow from the stent and into the ampulla during endoscopic retrograde cholangiopancreatography (ERCP) without clinical signs and/or symptoms of biliary obstruction. Criterion for bile leak resolution at ERCP is defined as absence of contrast extravasation from the common bile duct, cystic duct remanent, or gall blad-der fossa. Rate of complications such as migration, and instent occlusion were recorded. Failure of endoscopic therapy was defined as persistent biliary stenosis or continuous biliary leakage after 12 mo of stent placement. RESULTS: All 17 patients underwent successful FC- SEMS placement and removal. Etiologies of BBS included: cholecystectomies (n=8), cholelithiasis (n=2), hepatic artery compression (n=1), pancreatitis (n=2), and Whipple procedure (n=1). All bile leaks occurred following cholecystectomy. The anatomic location of BBS varied: distal common bile duct (n=7), common hepatic duct (n=1), hepaticojejunal anastomosis (n=2), right intrahepatic duct (n=1), and choledochoduo-denal anastomatic junction (n=1). All bile leaks were found to be at the cystic duct. Twelve of 17 patients had failed prior stent placement or exchange. Resolution of the biliary strictures and bile leaks was achieved in 16 of 17 patients (94%). The overall median stent time was 63 d (range 27-251 d). The median stent time for the BBS group and bile leak group was 62 ± 58 d (range 27-199 d) and 92 ± 81 d (range 48-251 d), respectively. All 17 patients underwent successful FCSEMS removal. Long term follow-up was obtained for a median of 575 d (range 28-1435 d). Complications occurred in 5 of 17 patients (29%) and included: migration (n=2), stent clogging (n=1), cholangitis (n=1), and sepsis with hepatic abscess (n=1). CONCLUSION: Placement of fully covered self-expanding metal stents may be used in the management of benign biliary strictures and bile leaks with a low rate of complications.

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 ! and I） 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.

Bilateral vs unilateral placement of metal stents for inoperable highgrade hilar biliary strictures: A systemic review and meta-analysis

BACKGROUND Bilateral vs unilateral biliary stenting is used for palliation in malignant biliary obstruction.No clear data is available to compare the efficacy and safety of bilateral biliary stenting over unilateral stenting.AIM To assess the efficacy and safety of bilateral vs unilateral biliary drainage in inoperable malignant hilar obstruction.METHODS PubMed,Embase,Scopus,and Cochrane databases,as well as secondary sources(bibliographic review of selected articles and major GI proceedings),were searched through January 2019.The primary outcome was the re-intervention rate.Secondary outcomes were a technical success,early and late complications,and stent malfunction rate.Pooled odds ratio(OR)and 95%confidence interval(CI)were calculated for each outcome.RESULTS A total of 9 studies were included(2 prospective Randomized Controlled Study,5 retrospective studies,and 2 abstracts),involving 782 patients with malignant hilar obstruction.Bilateral stenting had significantly lower re-intervention rate compared with unilateral drainage(OR=0.59,95%CI:0.40-0.87,P=0.009).There was no difference in the technical success rate(OR=0.7,CI:0.42-1.17,P=0.17),early complication rate(OR=1.56,CI:0.31-7.75,P=0.59),late complication rate(OR=0.91,CI:0.58-1.41,P=0.56)and stent malfunction(OR=0.69,CI:0.42-1.12,P=0.14)between bilateral and unilateral stenting for malignant hilar biliary strictures.CONCLUSION Bilateral biliary drainage had a lower re-intervention rate as compared to unilateral drainage for high grade inoperable malignant biliary strictures,with no significant difference in technical success,and early or late complication rates.

Mechanism of benign biliary stricture: A morphological and immunohistochemical study

AIM: To explore the mechanism of benign biliary stricture. METHODS: A model of trauma of bile duct was established in 28 dogs. The anastomosed tissues were resected and examined by light and electron microscopes on day 3, in wk 1, 3 and mo 3, 6 after operation. CD68, TGF-β1 and α-SMA were examined by immunohistochemical staining, respectively. RESULTS: The mucosal epithelium of the bile duct was slowly recovered, chronic inflammation lasted for a long time, fibroblasts proliferated actively, extracellular matrix was over-deposited. Myofibroblasts functioned actively and lasted through the whole process. The expression of macrophages in lamina propria under mucosa, TGF-β1 in granulation tissue, fibroblasts and endothelial cells of blood vessels, oc-SMA in myofiroblasts were rather strong from the 1st wk to the 6th mo after operation. CONCLUSION: The type of healing occurring in bile duct belongs to overhealing. Myofibroblasts are the main cause for scar contracture and stricture of bile duct. High expressions of CD68, TGF-β1 and a-SMA are closely related to the active proliferation of fibroblasts, extracellular matrix over-deposition and scar contracture of bile duct.

Role of endoscopic retrograde cholangiopancreatography inthe management of benign biliary strictures:What's new?

Benign biliary strictures comprise a heterogeneous group of diseases. The most common strictures amenable to endoscopic treatment are post-cholecystectomy, post-liver transplantation, related to primary sclerosing cholangitis and to chronic pancreatitis. Endoscopic treatment of benign biliary strictures is widely used as first line therapy, since it is effective, safe, noninvasive and repeatable. Endoscopic techniques currently used are dilation, multiple plastic stents insertion and fully covered self-expandable metal stents. The main indication for dilation alone is primary sclerosing cholangitis related strictures. In the vast majority of the remaining cases, temporary placement of multiple plastic stents with/without dilation is considered the treatment of choice. Although this approach is effective, it requires multiple endoscopic sessions due to the short duration of stent patency. Fully covered self-expandable metal stents appear as a good alternative to plastic stents, since they have an increased radial diameter, longer stent patency, easier insertion technique and similar efficacy. Recent advances in endoscopic technique and various devices have allowed successful treatment in most cases. The development of novel endoscopic techniques and devices is still ongoing.

Placement of removable metal biliary stent in post-orthotopic liver transplantation anastomotic stricture

Postoperative biliary strictures are the most common cause of benign biliary stricture in Western countries, secondary to either operative injury or bile duct anastomotic stricture following orthotopic liver transplantation(OLT).Surgery or endoscopic interventions are the mainstay of treatment for benign biliary strictures.We aim to report the outcome of 2 patients with refractory anastomotic biliary stricture post-OLT,who had successful temporary placement of a prototype removable covered self-expandable metal stent(RCSEMS).These 2 patients(both men,aged 44 and 53 years)were given temporary placement of a prototype RCSEMS (8.5 Fr gauge delivery system,8 mm×40 mm stent dimensions)in the common bile duct across the biliary stricture.There was no morbidity associated with stent placement and removal in these 2 cases.Clinical parameters improved after the RCSEMS placement.Longterm biliary patency was achieved in both the patients. No further biliary intervention was required within 14 and 18 mo follow-up after stent removal.

Endoscopic ultrasonography can diagnose distal biliary strictures without a mass on computed tomography

AIM:To assess the diagnostic ability of endoscopic ultrasonography(EUS)for evaluating causes of dista biliary strictures shown on endoscopic retrograde chol angiopancreatography(ERCP)or magnetic resonance cholangiopancreatography(MRCP),even without iden tifiable mass on computed tomography(CT). METHODS:The diagnostic ability of EUS was retro spectively analyzed and compared with that of routine cytology(RC)and tumor markers in 34 patients with distal biliary strictures detected by ERCP or MRCP a Dokkyo Medical School Hospital from December 2005 to December 2008,without any adjacent mass or ec centric thickening of the bile duct on CT that could cause biliary strictures.Findings considered as benign strictures on EUS included preservation of the normasonographic layers of the bile duct wall,irrespective of the presence of a mass lesion.Other strictures were considered malignant.Final diagnosis of underlying diseases was made by pathological examination in 18 cases after surgical removal of the samples,and by clinical follow-up for>10 mo in 16 cases. RESULTS:Seventeen patients(50%)were finally di- agnosed with benign conditions,including 6"normal" subjects,while 17 patients(50%)were diagnosed with malignant disease.In terms of diagnostic ability,EUS showed 94.1%sensitivity,82.3%specificity,84.2% positive predictive value,93.3%negative predictive value(NPV)and 88.2%accuracy for identifying ma- lignant and benign strictures.EUS was more sensi- tive than RC(94.1%vs 62.5%,P=0.039).NPV was also better for EUS than for RC(93.3%vs 57.5%,P= 0.035).In addition,EUS provided significantly higher sensitivity than tumor markers using 100 U/mL as the cutoff level of carbohydrate antigen 19-9(94.1%vs 53%,P=0.017).On EUS,biliary stricture that was fi- nally diagnosed as malignant showed as a hypoechoic, irregular mass,with obstruction of the biliary duct and invasion to surrounding tissues. CONCLUSION:EUS can diagnose biliary strictures caused by malignant tumors that are undetectable on CT.Earlier detection by EUS would provide more therapeutic options for patients with early-stage pancreaticobiliary cancer.

Role of transforming growth factor-beta signaling pathway in pathogenesis of benign biliary stricture

AIM: To characterize the expression of members of the transforming growth factor-beta (TGF-β)/Smad/ connective tissue growth factor (CTGF) signaling pathway in the tissue of benign biliary stricture, and to investigate the effect of TGF-β signaling pathway in the pathogenesis of benign biliary stricture. METHODS: Paraffin embedded materials from 23 cases of benign biliary stricture were analyzed for members of the TGF-β/Smad/CTGF signaling pathway. TGF-β_1, TβRⅠ, TβRⅡ, Smad4, Smad7 and CTGF protein were detected by immunohistochemical strepto-advidinbiotin complex method, and CTGF mRNA was evaluated by hybridization in situ, while 6 cases of normal bile duct served as controls. The percentages of positive cells were counted. The correlation between TGF-β_1, Smad4 and CTGF was analyzed. RESULTS: The positive expression ratios of TGF-β_1, TβRⅠ , TβRⅡ , Smad4, CTGF and CTGF mRNA in 23 cases with benign biliary stricture were 91.3%, 82.6%, 87.0%, 78.3%, 82.6% and 65.2%, respectively, signifi cantly higher than that in 6 cases of normal bile duct respectively (vs 33.3%, 16.7%, 50.0%, 33.3%, 50.0%, 16.7%, respectively, P < 0.05). The positiveexpression ratio of Smad7 in cases with benign biliary stricture was 70.0%, higher than that in normal bile duct, but this difference is not statistically signifi cant 70.0% vs 50%, P > 0.05). There was a positive correlation between positive expression of TGF-β_1, Smad4 and CTGF in cases with benign biliary stricture. CONCLUSION: The high expression of TGF-β/Smad/ CTGF signaling pathway plays an important role in the pathogenesis of benign biliary stricture.

Endoscopic palliation of malignant biliary stricture

Malignant biliary strictures often present late after the window for curative resection has elapsed. In such patients, the goal of therapy is typically focused on palliation. While historically, palliative measures were performed surgically, the advent of endoscopic intervention offers minimally invasive options to provide relief of symptoms, improve quality of life, and in some cases, increase survival of these patients. Some of these therapies, such as endoscopic biliary decompression, have become mainstays of treatment for decades, whereas newer modalities, including radiofrequency ablation, and photodynamic therapy offer additional options for patients with incurable biliary malignancies.

Efficacy of multiple biliary stenting for refractory benign biliary strictures due to chronic calcifying pancreatitis

AIMTo investigate endoscopic therapy efficacy for refractory benign biliary strictures (BBS) with multiple biliary stenting and clarify predictors. METHODSTen consecutive patients with stones in the pancreatic head and BBS due to chronic pancreatitis who underwent endoscopic therapy were evaluated. Endoscopic insertion of a single stent failed in all patients. We used plastic stents (7F, 8.5F, and 10F) and increased stents at intervals of 2 or 3 mo. Stents were removed approximately 1 year after initial stenting. BBS and common bile duct (CBD) diameter were evaluated using cholangiography. Patients were followed for &ge; 6 mo after therapy, interviewed for cholestasis symptoms, and underwent liver function testing every visit. Patients with complete and incomplete stricture dilations were compared. RESULTSEndoscopic therapy was completed in 8 (80%) patients, whereas 2 (20%) patients could not continue therapy because of severe acute cholangitis and abdominal abscess, respectively. The mean number of stents was 4.1 &plusmn; 1.2. In two (20%) patients, BBS did not improve; thus, a biliary stent was inserted. BBS improved in six (60%) patients. CBD diameter improved more significantly in the complete group than in the incomplete group (6.1 &plusmn; 1.8 mm vs 13.7 &plusmn; 2.2 mm, respectively, P = 0.010). Stricture length was significantly associated with complete stricture dilation (complete group; 20.5 &plusmn; 3.0 mm, incomplete group; 29.0 &plusmn; 5.1 mm, P = 0.011). Acute cholangitis did not recur during the mean follow-up period of 20.6 &plusmn; 7.3 mo. CONCLUSIONSequential endoscopic insertion of multiple stents is effective for refractory BBS caused by chronic calcifying pancreatitis. BBS length calculation can improve patient selection procedure for therapy.

Digital single-operator cholangioscopy for biliary stricture after cadaveric liver transplantation

BACKGROUND Biliary strictures after liver transplantation(LT)remain clinically arduous and challenging situations,and endoscopic retrograde cholangiopancreatography(ERCP)has been considered as the gold standard for the management of biliary strictures after LT.Nevertheless,in the treatment of biliary strictures after LT with ERCP,many studies show that there is a large variation in diagnostic accuracy and therapeutic success rate.Digital single-operator peroral cholangioscopy(DSOC)is considered a valuable diagnostic modality for indeterminate biliary strictures.AIM To evaluate DSOC in addition to ERCP for management of biliary strictures after LT.METHODS Nineteen patients with duct-to-duct biliary reconstruction who underwent ERCP for suspected biliary complications between March 2019 and March 2020 at Beijing Chaoyang Hospital,Capital Medical University,were consecutively enrolled in this observational study.After evaluating bile ducts using fluoroscopy,cholangioscopy using a modern digital single-operator cholangioscopy system(SpyGlass DS^(TM))was performed during the same procedure with patients under conscious sedation.All patients received peri-interventional antibiotic prophylaxis.Biliary strictures after LT were classified according to the manifestations of choledochoscopic strictures and the manifestations of transplanted hepatobiliary ducts.RESULTS Twenty-one biliary strictures were found in a total of 19 patients,among which anastomotic strictures were evident in 18(94.7%)patients,while non-anastomotic strictures in 2(10.5%),and space-occupying lesions in 1(5.3%).Stones were found in 11(57.9%)and loose sutures in 8(42.1%).A benefit of cholangioscopy was seen in 15(78.9%)patients.Cholangioscopy was crucial for selective guidewire placement prior to planned intervention in 4 patients.It was instrumental in identifying biliary stone and/or loose sutures in 9 patients in whom ERCP failed.It also provided a direct vision for laser lithotripsy.A spaceoccupying lesion in the bile duct was diagnosed by cholangioscopy in one patient.Patients with biliary stricture after LT displayed four types:(A)mild inflammatory change(n=9);(B)acute inflammatory change edema,ulceration,and sloughing(n=3);(C)chronic inflammatory change;and(D)acute suppurative change.Complications were seen in three patients with post-interventional cholangitis and another three with hyperamylasemia.CONCLUSION DSOC can provide important diagnostic information,helping plan and perform interventional procedures in LT-related biliary strictures.