Biliary Tract Disorders Research Articles

Hepatobiliary and pancreatic disorders in celiac disease

A variety of hepatic and biliary tract disorders may complicate the clinical course of celiac disease. Some of these have been hypothesized to share common genetic factors or have a common immunopathogenesis, such as primary biliary cirrhosis, primary sclerosing cholangitis and autoimmune forms of hepatitis or cholangitis. Other hepatic changes in celiac disease may be associated with malnutrition resulting from impaired nutrient absorption, including hepatic steatosis. In addition, celiac disease may be associated with rare hepatic complications, such as hepatic T-cell lymphoma. Finally, pancreatic exocrine function may be impaired in celiac disease and represent a cause of treatment failure.

Effect of maintenance therapy for childhood with acute lymphoblastic leukaemia by combination of methotrexate and 6–mercaptopurine on the liver.

Seven of 30 children with acute lymphoblastic leukaemia (ALL) receiving maintenance therapy (MT) consisting of daily oral 6–mercaptopurine (6MP) and weekly methotrexate (MTX) developed both hepatocellular destruction and intrahepatic cholestasis (with abnormally elevated levels of serum aminotransferases enzymes GOT, GPT that mainly indicate liver cell destruction, and alkaline phosphatase, gammaglutamyl transferase enzymes, as well as total serum bilirubin that mainly indicate biliary tract disorder). In the remaining 23 patients, the serum levels of alkaline phosphatase (ALP), gammaglutamyl transferase (GGT) enzymes, and total serum bilirubin (TSB) . were within the normal reference ranges for these parameters of the liver function tests while 13 patients. have abnormally elevated serum glutamic oxaloacetate transaminase (GOT) and glutamic pyruvate transamiase (GPT). The long–term use of MTX (20 mg/m2/week) and 6MP (75 mg/m2/day) during the MT for childhood ALL may lead to the development of hepatocellular destruction mainly induced by MTX, and intrahepatic mainly induced by 6MP.

Cholangitis: A histologic classification based on patterns of injury in liver biopsies

Inflammatory disorders of the biliary tract present difficult diagnostic problems in liver needle biopsies. The aim of this study was to perform a detailed histologic analysis of liver biopsies from patients with biliary tract disorders, classify them by pattern of inflammation, and determine the accuracy of the histologic classification by clinical follow-up. Percutaneous liver needle biopsies from the surgical pathology files of UmassMemorial Healthcare (UMMHC) from 2000 to 2003 with a diagnosis suggesting a biliary tract process ( n = 32 ) and four biopsies from cases with systemic non-biliary tract disorders were analyzed for multiple histologic features and classified as one of five patterns: acute cholangitis/pericholangitis (ACP), lymphocytic cholangitis (LC), granulomatous (G), ductopenia (D), or non-specific (NS). When compared to the “gold standard” diagnosis based on all clinical data, the concordance between the histologic classification and the clinical diagnosis was: 50% for ACP and bile duct obstruction; 77% for LC and immune-mediated cholangitis NOS; 100% for G and G cholangitis; 100% for D and idiopathic adulthood D; and 50% for NS and non-biliary tract disorders. Our findings suggest that classifying biopsies by pattern of injury is helpful in guiding the subsequent clinical work-up. ACP pattern correlates with bile duct obstruction, infection, and ischemia. LC correlates with serologic studies supporting immune-mediated processes. G pattern suggests further work-up for PBC, drug, tuberculosis, or sarcoidosis. D pattern establishes the clinical diagnosis. NS pattern includes cases of primary sclerosing cholangitis, which cannot be diagnosed by biopsy alone.

Liver and biliary tract disorders

Department of Veterans Affairs Medical Center and University of Michigan School of Medicine, Ann Arbor, Michigan, USA Correspondence to Richard H. Moseley, MD, Chief, Medical Service (111), Veterans Affairs Medical Center, 2215 Fuller Rd, Ann Arbor, MI 48105, USA E-mail: [email protected]

Pediatric hepatobiliary disease

This review summarizes recent advancements occurring over the past year in the field of pediatric hepatology. They have helped in the understanding and treatment of several liver and biliary tract disorders of childhood. Recent advancements in the areas of childhood primary sclerosing cholangitis, nonalcoholic fatty liver disease, acute liver failure, liver transplantation, neonatal hemochromatosis, and the Biliary Atresia Research Consortium have been summarized. Developments and continued research in these areas have the potential to bring significant benefits to children affected by these disorders.

P0820 ENDOSCOPIC THERAPY OF BILIARY AND PANCREATIC DISORDERS IN CHILDREN

Introduction: Endoscopic Retrograde Cholangiopancreatography (ERCP) is widely applied in adult patients for diagnostic and therapeutic management of biliary tract and pancreatic disorders. The use of therapeutic ERCP in children has been limited. In this abstract we document our therapeutic experience with 58 ERCPs performed in 51 children during the last 10 years and 14 therapeutic procedure rapported. Methods: During a 10 year period from 1990 to 2000, 58 ERCP’s were performed in 51 children (18 girls and 33 boys, aged 6 months to 15 years). All ERCP was performed by the same endoscopist under general anesthesia. The study was retrospective. The patients were classified as having biliary or pancreatic or pancreatic-biliary disease who indicated a ERCP. The results were noted as well as eventual therapy and correlated with the outcome. Results: ERCP was successful in 53 attempts and therapeutic management was proposed in 17 cases and realised in 14 cases. Many of the procedure were combinated and complications were rare: 1 mild pancreatitis and 1 duodenal fissuration with favorable outcome.Pancreatic disease was the most frequent indication (28 children), a therapeutic intervention was proposed in 6 cases but done in 4 cases. Those 2 failures of catheterisation of pancreatic duct in patients with a pancreatic trauma. The therapeutic intervention done in the 4 cases were:pancreatic sphincterotomy (n=3), wirsung balloon dilatation (n=1), stent placement in wirsung (n=4), stent extraction (n=2), stone extraction (n=2).Biliary tract disorders was the second most frequent indication (15 children).A therapeutic intervention was proposed in 6 cases and realised in 5 cases (1 failure of cannulation of the common bile duct):biliary sphincterotomy (n=4), papillary balloon dilatation (n=1), stone extraction (n=2). Pancreaticobiliary disease was the last frequent indication (8 children).A therapeutic intervention was realised in 3 cases: biliary sphincterotomy (n=3), papillary balloon dilatation (n=1), stone extraction (n=1). Conclusion: Our study inclued a great number of diagnostic ERCP in children but a few number of therapeutic ERCP(14/53). The most common intervention are sphincterotomy and stone extraction. The outcome (with only 2 years) was favorable in 75% cases those avoiding surgery. Few data are avalable in the use of therapeutic ERCP in children an our result confirmed that it is a safe procedure in selected children. The long term complications of sphincterotomy or use of stents in children are unknown and must be established.

Editorial overview: Liver and biliary tract disorders

Editorial overview: Liver and biliary tract disorders

Oxysterols induce cyclooxygenase-2 expression in cholangiocytes: implications for biliary tract carcinogenesis.

Cyclooxygenase-2 (COX-2), which is expressed by cholangiocytes in biliary tract disorders, has recently been implicated in biliary tract carcinogenesis. The mechanisms responsible for this COX-2 expression remain unclear. In human diseases, bile contains oxygenated derivatives of cholesterol (oxysterols) which possess diverse biological properties. Therefore, we determined if oxysterols modulate COX-2 expression. The effect of an oxysterol (22(R)-hydroxycholesterol, 22-HC) on COX-2 expression in KMBC cells, a human cholangiocarcinoma cell line, was examined. 22-HC enhanced COX-2 protein expression. This oxysterol activated p42/44 and p38 MAPK, but not JNK 1/2. A p42/44 MAPK inhibitor did not block COX-2 induction, while p38 MAPK inhibitor effectively attenuated COX-2 induction. Although COX-2 mRNA levels were increased by 22-HC, this increase was not transcriptionally regulated, as 22-OH did not increase activity in a COX-2 promoter gene assay. In contrast, COX-2 mRNA stability was augmented by 22-HC treatment, and this effect was reversed by a p38 MAPK inhibitor. In conclusion, the results demonstrate that the oxysterol 22-HC stabilizes COX-2 mRNA via a p38 MAPK-dependent mechanism. This enhanced COX-2 protein expression by oxysterols may participate in the genesis and progression of cholangiocarcinoma.

Acalculous biliary tract disorders: the value of fatty meal-cholescintigraphy

The management of patients with symptoms consistent with biliary tract disease but without evidence of cholelithiasis is difficult. This study was undertaken to test the value of cholescintigraphy in predicting the success of cholecystectomy in patients with acalculous biliary tract disorders. A prospective study was carried out on 73 patients presenting with recurrent upper quadrant pain without documented evidence of gallstones on ultrasound. Fatty meal-cholescintigraphy was performed on all patients and the gallbladder ejection fraction was calculated. Laparoscopic cholecystectomy was performed in patients with ejection fractions of <40%, followed by histopathological analysis and assessment of symptomatic improvement. There were 43 men and 30 women with a mean age of 33.4 years. Forty-one patients had abnormal ejection fractions. All except one patient had a laparoscopic cholecystectomy. The pathological diagnosis of chronic cholecystitis was made in 33 patients and acute on chronic cholecystitis documented in four patients. Five patients had cholesterolosis and two of these had associated chronic cholecystitis. All except three patients had complete relief of symptoms post-operatively with a mean follow-up of 10 months. Modified cholescintigraphy is a useful test for predicting which patients with acalculous biliary tract disease benefit from a cholecystectomy.

Direct Cholangioscopy

Since it was first advocated by Takada et al. in 1974 [1], percutaneous transhepatic cholangioscopy (PTCS) has been utilized to manage a variety of biliary tract disorders. Percutaneous lithotomy using PTCS has become one of the most important nonsurgical forms of treatment for hepatolithiasis. The diagnostic and therapeutic efficacy of PTCS has been widely accepted, and clinical applications for this procedure have expanded to provide more precise preoperative diagnosis of biliary malignancy and to treat difficult biliary stenoses or gallstones using improved and less invasive instruments. PTCS has also been used in the management of diverse biliary tract disorders, including biliary neoplasms, calculi, strictures (benign and malignant), and evaluation of biliary-enteric anastomoses. PTCS appears to be of particular benefit in managing poor surgical candidates with diffuse intrahepatic stones.

Pyogenic Liver Abscess.

Pyogenic liver abscess is an important and often life-threatening disorder. It is commonly caused by underlying disease of the biliary system, but more frequently, no predisposing disorder can be identified. Its diagnosis requires a high index of suspicion and imaging of the liver. The optimal treatment of pyogenic liver abscess is percutaneous drainage and intravenous broad-spectrum antibiotics with activity against enteric aerobic and anaerobic bacteria. Blood and abscess cultures should be obtained and amebic liver abscess carefully eliminated when the diagnosis is in doubt. Surgical drainage, preferably laparoscopic, is reserved for patients with complicated abscesses or after failure of response to initial medical therapy. Possible primary predisposing conditions to pyogenic liver abscess, such as biliary tract disorders, should be sought and managed accordingly. Intravenous antibiotics should be administered for a period of 2 weeks, followed by a more prolonged course of oral antibiotics. The choice and duration of antibiotic therapy, and the need for further intervention are determined by microbiologic data, the patient's clinical response, and repeated imaging studies.

Epidemiology and natural history of common bile duct stones and prediction of disease.

Gallstones are extremely common in Western societies. Approximately l5% of Americans have gallstones, and approximately 650,000 to 700,000 cholecystectomies are performed every year.1. More than 98% of all biliary tract disorders are in some way related to gallstones. Symptoms and complications related to gallstones are among the most costly digestive disorders, at an estimated annual cost of almost $6.5 billion, exceeding the combined total for chronic liver disease and cirrhosis ($1.6 billion), chronic hepatitis C ($0.8 billion) and diseases of the pancreas ($2.2 billion).2 Stones are most commonly found in the gallbladder, but gallstones can pass through the cystic duct to become intrahepatic or extrahepatic bile duct stones. Ten to fifteen percent of people with gallbladder stones will harbor concomitant common bile duct stones. In some situations, bile duct stones can develop as primary intrahepatic or extrahepatic stones without involving the gallbladder. Primary bile duct concretions are much more common in patients of Asian descent compared with those of European descent. In Western societies, gallstones are composed primarily of cholesterol. EPIDEMIOLOGY OF CHOLESTEROL GALLSTONES The epidemiology of cholesterol gallstones has been examined in multiple studies. Risk factors for gallstones include behavioral factors such as nutrition, obesity, weight loss, and physical activity as well as biologic factors such as increasing age, female sex, race, and serum lipid levels.

Epidemiology and natural history of common bile duct stones and prediction of disease

Gallstones are extremely common in Western societies. Approximately 15% of Americans have gallstones, and approximately 650,000 to 700,000 cholecystectomies are performed every year.1. More than 98% of all biliary tract disorders are in some way related to gallstones. Symptoms and complications related to gallstones are among the most costly digestive disorders, at an estimated annual cost of almost $6.5 billion, exceeding the combined total for chronic liver disease and cirrhosis ($1.6 billion), chronic hepatitis C ($0.8 billion) and diseases of the pancreas ($2.2 billion).

Pancreatic and biliary tract disorders in inflammatory bowel disease.

Hepatobiliary disorders occur frequently in patients with IBD, with PSC and cholangiocarcinoma being the most clinically significant for endoscopists. Endoscopic therapy for PSC is effective in improving symptoms, biochemical parameters, and radiographic abnormalities. Endoscopic therapy may also confer survival benefit, but this has yet to be confirmed in randomized, controlled trials. Treatment should be restricted to those individuals with a rapid decline in liver function testing or those with recurrent cholangitis. Cholangiocarcinoma is a serious complication of PSC and carries an extremely poor prognosis. ERCP with brush cytology has a relatively low sensitivity and the diagnosis is usually made after the disease has become metastatic. Malignant biliary obstruction can be palliated by endoscopic stenting. Photodynamic therapy is a promising experimental technique that may confer symptomatic and survival benefit in patients with nonresectable, advanced cholangiocarcinoma. IBD patients also have an elevated risk for developing acute and chronic pancreatitis as well as pancreatic insufficiency. The majority of cases of acute pancreatitis are likely due to medication side effects and local structural complications of IBD. The remainder may possibly represent true extraintestinal manifestations of IBD. Chronic pancreatitis is frequently subclinical, but may be accompanied by clinically relevant exocrine insufficiency. ERCP is the test of choice for the diagnosis of chronic pancreatitis, but the role of endoscopy in the therapeutic management of IBD-associated chronic pancreatitis remains to be defined.

Increased transforming growth factor beta in pure pancreatic juice in pancreatitis.

Cytokines play an important role in the regulation of inflammation and fibrosis in the development of chronic pancreatitis. In this study, transforming growth factor beta (TGFbeta), interleukin (IL)-6, IL-10, and tumor necrosis factor alpha (TNFalpha) were measured in pure pancreatic juice obtained through pancreatic duct cannulation. Twenty patients with chronic pancreatitis were compared with six patients thought to be free of pancreatic disease who were undergoing endoscopic retrograde cholangiopancreatography for biliary tract disorders. TGFbeta was detected in 17 of 20 patients with chronic pancreatitis tested (85%), compared with only one patient in the control group (17%). There was no measurable amount of IL-10, IL-6, or TNFalpha in any of the pure pancreatic juice samples from any of the patients. These data indicate that TGFbeta may play an active role in the advancement of pancreatitis by causing local inflammation and inducing fibroblasts to secrete collagen. This finding may be relevant in the future for identifying patients whose conditions may advance to chronic pancreatitis, and blocking the effects of TGFbeta could have therapeutic effects.

Effects of bile salts on cholestan-3β,5α,6β-triol-induced apoptosis in dog gallbladder epithelial cells

Oxysterols are cytotoxic agents. The gallbladder epithelium is exposed to high concentrations of oxysterols, and so elucidating the mechanisms of cytotoxicity in this organ may enhance our understanding of the pathogenesis of biliary tract disorders. We investigated the cytotoxic effects of the oxysterol cholestan-3β,5α,6β-triol (TriolC) on dog gallbladder epithelial cells. Apoptosis was the major form of cytotoxicity, as determined by analysis of nuclear morphologic changes and by multiparameter flow cytometry. Hydrophobic bile salts are known to have cytotoxic effects, whereas hydrophilic bile salts have cytoprotective effects. We therefore examined whether the hydrophobic bile acid taurodeoxycholic acid (TDC) and the hydrophilic bile acid tauroursodeoxycholic acid (TUDC) had modifying effects on oxysterol-induced cytotoxicity. TriolC caused an increase in the number of apoptotic cells from 14±11% (control) to 48±12% of total cells ( P<0.01). After combining TriolC with TDC, cell apoptosis increased to 63±16% ( P<0.05), whereas after addition of TUDC, the number of apoptotic cells decreased to 31±12% ( P<0.05) of total cells. In summary, oxysterols such as TriolC induce apoptosis. Hydrophobic bile salts enhance TriolC-induced apoptosis, whereas hydrophilic bile salts diminish TriolC-induced apoptosis. These results suggest that interactions between oxysterols and bile salts play a role in the pathophysiology of biliary tract disorders.

Endoscopic therapy of chronic pancreatitis

Chronic pancreatitis is an inflammatory process characterized by destruction of pancreatic parenchyma and ductal structures with formation of fibrosis. Pain is the predominant symptom of chronic pancreatitis and its origin appears to be multifactorial. 1 Steer ML Waxman I Freedman S. Chronic pancreatitis. N Engl J Med. 1995; 332: 1482-1490 Crossref PubMed Scopus (585) Google Scholar , 2 Widdison AL Alvarez C Karanjia ND Reber HA. Experimental evidence of beneficial effects of ductal decompression in chronic pancreatitis. Endoscopy. 1991; 23: 151-154 Crossref PubMed Scopus (51) Google Scholar , 3 Karanjia ND Reber HA. The cause and management of the pain of chronic pancreatitis. Gastrointest Clin N Amer. 1990; 19: 895-904 PubMed Google Scholar , 4 Lo SK Lewis MPN Reber PU Patel A Sherman S Ashley SW Reber HA. In-vivo endoscopic trans-sphincteric measurement of pancreatic blood flow (PBF) in humans. Gastrointest Endosc. 1996; 43: 409A Abstract Full Text PDF Scopus (3) Google Scholar The multiplicity of causes of pain helps explain the mixed results achieved by current methods of therapy. Most therapeutic efforts in the treatment of chronic pancreatitis are directed toward control of symptoms. Medical therapies (dietary alterations, analgesics, nerve blocks, oral enzyme supplements, octreotide) are variably effective in relieving pain, 1 Steer ML Waxman I Freedman S. Chronic pancreatitis. N Engl J Med. 1995; 332: 1482-1490 Crossref PubMed Scopus (585) Google Scholar leaving surgical therapy as the main therapeutic option for patients who fail to improve with medical management. Early postoperative pain relief is seen in 80-90% of patients; however, pain recurs in 20-50% during long-term follow-up. 5 Bradley EL. Long-term results of pancreatojejunostomy in patients with chronic pancreatitis. Am J Surg. 1987; 153: 207-213 Abstract Full Text PDF PubMed Scopus (197) Google Scholar , 6 Malfertheiner P Buchler M. Indications for endoscopic or surgical therapy in chronic pancreatitis. Endoscopy. 1991; 23: 185-190 Crossref PubMed Scopus (26) Google Scholar Surgical drainage procedures are associated with a morbidity rate of 20-40% and an average mortality rate of 4%. 3 Karanjia ND Reber HA. The cause and management of the pain of chronic pancreatitis. Gastrointest Clin N Amer. 1990; 19: 895-904 PubMed Google Scholar While endoscopic therapy has revolutionized the approach to a variety of biliary tract disorders, it is only recently that the indications for therapeutic endoscopy have been expanded to include disorders of the pancreas. 7 Bedford RA Howerton DH Geenen JE. The current role of ERCP in the treatment of benign pancreatic disease. Endoscopy. 1994; 26: 113-119 Crossref PubMed Scopus (20) Google Scholar , 8 Kozarek RA Traverso LW. Endotherapy of chronic pancreatitis. Int J Pancreatol. 1996; 19: 93-102 PubMed Google Scholar , 9 Kaikaus RM Geenen JE. Current role of ERCP in the management of benign pancreatic disease. Endoscopy. 1996; 28: 131-137 Crossref Scopus (9) Google Scholar , 10 Sherman S Lehman GA. Endoscopic therapy of pancreatic disease. The Gastroenterologist. 1997; 5: 262-277 PubMed Google Scholar , 11 Kozarek RA Chronic pancreatitis in 1994: Is there a role for endoscopic treatment?. Endoscopy. 1994; 26: 625-628 Crossref PubMed Scopus (18) Google Scholar Although the endoscopic approach has not been compared directly to surgery, endoscopic drainage is appealing in that it may offer an alternative to surgical drainage procedures with generally less morbidity and mortality. Furthermore, endoscopic procedures do not preclude subsequent surgery, if necessary. Moreover, the outcome from reducing the intraductal pressure by endoscopic methods may be a predictor for the success of surgical drainage. 12 Huibregtse K Smits ME. Endoscopic management of diseases of the pancreas. Am J Gastroenterol. 1994; 89: S66-S77 PubMed Google Scholar

7022 One uniform endosonographic layer reflects a thin subserosal adipose tissue of the normal gallbladder wall.

Introduction and aim: Endoscopic ultrasonography (EUS) plays a major role in diagnosis of the gallbladder lesions. The normal gallbladder wall has been demonstrated to consist of 3 layers on EUS images. It is generally accepted that the 2nd and the 3rd layers include the muscularis propria and subserosal fibrous tissue, and the subserosal adipose tissue, respectively. However these 3 layers cannot be seen in some normal gallbladder by EUS images. Therefore this study was aimed to clarify the cause of these 2 different EUS images seen normal gallbladder by histological study of the gallbladder wall performed simultaneously. Materials and methods: Gallbladder specimens from 12 autopsy cases without biliary tract disorders, 6 with the three EUS layers (goup A) and 6 with one uniform layer (group B), were enrolled in this study. Two needles were stabbed into the gallbladder wall from the mucosa to perform EUS and histological study for the same area of the specimen. For this study an Olympus GFUMQ 240 with a frequency of 7.5MHz was used. Results: Histology of the specimens were summarized in the table. The thickness of the muscularis propria and fibrous layer showed no significant differences between group A and B. While the thickness of the adipose layer of group B was determined to be one half of group A. Conclusions: This study indicates that the one uniform layer seen in normal gallbladder on EUS images reflects a thin subserosal adipose layer.

Experience with percutaneous transhepatic cholangioscopy (PTCS) in the management of biliary tract disease

Biliary tract disorders often present significant management difficulties, particularly in patients who are poor surgical candidates. Percutaneous transhepatic cholangioscopy (PTCS) is an infrequently utilized alternative that might offer significant therapeutic benefit. We reviewed our experience with the use of this modality as a definitive therapy for biliary tract disorders. Patient records at the Atlanta VAMC and Emory University hospitals were reviewed. We identified 17 patients who had undergone 25 PTCS interventions between August 1994 and December 1998. The indications for PTCS included dilatation of biliary-enteric anastomoses in four patients, biliary stone removal (with or without lithotripsy) in eight patients, stricturoplasty in four patients, biopsy of suspected biliary neoplasms in seven patients, and removal of obstructing clot in one patient. Most procedures (n = 17) were performed through percutaneous transhepatic tracts (12-18 Fr) that were <1 week old. All tracts were dilated to operating size on the day of the procedure. All patients received periprocedural antibiotics. The interventions were successful in seven of eight stone removals, four of five stricturoplasties, three of four anastomotic dilatations, seven of seven biopsies, and the single clot removal. The only complication involved one episode of hemobilia, requiring angio-embolization of a small branch of the right hepatic artery. PTCS is a safe, useful, and well-tolerated adjunct to the more common endoscopic and surgical techniques for managing complicated biliary tract disorders. Our experience suggests that PTCS can be performed early, without prolonged sequential dilatation of the percutaneous transhepatic tract, and may allow avoidance of operation in high-risk surgical candidates.

The role of choledochoscopy in the diagnosis and management of biliary tract diseases

Background: The diagnosis and management of biliary tract disorders in certain cases may be incomplete without direct visualization of the bile ducts. Methods: We report our experience of 61 choledochoscopies (33 women, 27 men, mean age 44.6 years). Twenty patients had previously undergone orthotopic liver transplantation. All except two choledochoscopies were performed via the transpapillary route. Indications included suspected large bile duct stones in 18 patients, anastomotic strictures in 16, abnormal cholangiograms in 5, elevated liver function tests in 7, suspected cholangiocarcinoma in 4, occluded biliary metallic stent in 4, hemobilia in 4, primary sclerosing cholangitis in 2 and ischemic bile duct injury in 1 patient. Results: Choledochoscopy confirmed the anticipated diagnosis in 36 of 61 (59%) patients. Importantly, it provided additional unsuspected diagnostic information in 18 of the 61 (29.5%) patients. In addition, for patients in whom standard cholangiography was deemed abnormal, choledochoscopy demonstrated normal results in 7 (11.4%) patients. Fifty-two choledochoscopies were performed with therapeutic intentions, and the procedure was helpful in providing targeted treatment in 27 (44.2%) patients. Conclusions: Choledochoscopy is a safe and useful endoscopic modality that can provide specific diagnoses and direct treatment in various biliary tract diseases. The additional information provided by choledochoscopy may change overall patient management and outcome. (Gastrointest Endosc 1999;50:67-73.)