Useful predictors of bile duct stones in patients undergoing laparoscopic cholecystectomy. McGill Gallstone Treatment Group

Biochemical predictors for absence of common bile duct stones in patients undergoing laparoscopic cholecystectomy

BACKGROUND

To provide optimal selection of patients for preoperative endoscopic retrograde cholangiopancreatography or intraoperative cholangiography, we evaluated simple, noninvasive biochemical parameters as screening tests to predict the absence of common bile duct stones prior to laparoscopic cholecystectomy.

METHODS

A total of 1002 patients underwent laparoscopic cholecystectomy. Five biochemical parameters were measured preoperatively: gamma glutamyl transferase (GGT), alkaline phosphatase, total bilirubin, alanine aminotransferase, and aspartate aminotransferase. Conventional diagnostic tests, including ultrasound imaging, computed tomography, magnetic resonance imaging, common bile duct diameter, endoscopic retrograde cholangiopancreatography, and serum amylase were performed. Along with the five biochemical tests above, these diagnostic tests were scrutinized and compared as potential predictors for common bile duct stones.

RESULTS

Eighty-eight (8.8%) patients with gallstone disease who underwent laparoscopic cholecystectomy had concurrent common bile duct stones. Among all diagnostic tests, endoscopic retrograde cholangiopancreatography had the highest sensitivity (96.0%), specificity (99.1%), probability ratio (107.3), accuracy (98.0%), and positive predictive value (98.8%) in detecting common bile duct stones. At least one abnormal elevation among the five biochemical parameters had the highest sensitivity (87.5%). Total bilirubin had the highest specificity (87.5%), highest probability ratio (3.9), highest accuracy (84.1%), and highest positive predictive value (27.4%). All five biochemical predictors had high negative predictive values; gamma glutamyl transferase was highest (97.9%), while the lowest was total bilirubin (94.7%). Multivariate analysis showed only gamma glutamyl transferase, alkaline phosphatase, and total bilirubin to be independent predictors; gamma glutamyl transferase appeared to be the most powerful predictor (odds ratio 3.20).

CONCLUSION

Biochemical tests, especially gamma glutamyl transferase with 97.9% negative predictive value, are ideal noninvasive predictors for the absence of common bile duct stones in patients undergoing laparoscopic cholecystectomy. We suggest that unnecessary, costly, or risky procedures such as endoscopic retrograde cholangiopancreatography can be omitted prior to laparoscopic cholecystectomy in patients without abnormal elevation of these biochemical values.

An Economic Analysis of Hospital Charges for Choledocholithiasis by Different Treatment Strategies

The ideal management of presumed choledocholithiasis is controversial. We hypothesized that patients admitted with presumed choledocholithiasis would be better served financially to undergo laparoscopic cholecystectomy (LC) with possible intraoperative intervention versus preoperative endoscopic retrograde cholangiopancreatography followed by LC. A chart review was performed from September 1, 2000 to August 31, 2003. One hundred seventy-one consecutive patients identified with presumed choledocholithiasis were reviewed. Six patients were excluded because of missing charge data. Professional and technical fees from the total hospital charges were used for comparison. Three groups of patients were compared for charge analysis. Group 1 underwent LC with laparoscopic common bile duct exploration. Group 2 underwent LC with preoperative or postoperative endoscopic retrograde cholangiopancreatography. Group 3 was a control group of LC only. Student's t test was used for statistical analysis with a P value of <0.05 defined as statistically significant. P values reflect comparisons with Group 1. Group 1 charges were $13,026, Group 2 charges were $15,303, and Group 3 charges were $9,122. For suspected choledocholithiasis, LC with intraoperative intervention is the most economically advantageous approach.

Choledocholithiasis: Evolving standards for diagnosis and management

Cholelithiasis, one of the most common medical conditions leading to surgical intervention, affects approximately 10 % of the adult population in the United States. Choledocholithiasis develops in about 10%-20% of patients with gallbladder stones and the literature suggests that at least 3%-10% of patients undergoing cholecystectomy will have common bile duct (CBD) stones.

CBD stones may be discovered preoperatively, intraoperatively or postoperatively Multiple modalities are available for assessing patients for choledocholithiasis including laboratory tests, ultrasound, computed tomography scans (CT), and magnetic resonance cholangiopancreatography (MRCP). Intraoperative cholangiography during cholecystectomy can be used routinely or selectively to diagnose CBD stones.

The most common intervention for CBD stones is ERCP. Other commonly used interventions include intraoperative bile duct exploration, either laparoscopic or open. Percutaneous, transhepatic stone removal other novel techniques of biliary clearance have been devised. The availability of equipment and skilled practitioners who are facile with these techniques varies among institutions. The timing of the intervention is often dictated by the clinical situation.

Nonoperative imaging techniques in suspected biliary tract obstruction

Evaluation of suspected biliary tract obstruction is a common clinical problem. Clinical data such as history, physical examination, and laboratory tests can accurately identify up to 90% of patients whose jaundice is caused by extrahepatic obstruction. However, complete assessment of extrahepatic obstruction often requires the use of various imaging modalities to confirm the presence, level, and cause of obstruction, and to aid in treatment plan. In the present summary, the literature on competing technologies including endoscopic retrograde cholangiopancreatography (ERCP), percutaneous transhepatic cholangiopancreatography (PTC), endoscopic ultrasound (EUS), intraductal ultrasonography (IDUS), magnetic resonance cholangiopancreatography (MRCP), helical CT (hCT) and helical CT cholangiography (hCTC) with regards to diagnostic performance characteristics, technical success, safety, and cost-effectiveness is reviewed. Patients with obstructive jaundice secondary to choledocholithiasis or pancreaticobiliary malignancies are the primary focus of this review. Algorithms for the management of suspected obstructive jaundice are put forward based on current evidence. Published data suggest an increasing role for EUS and other noninvasive imaging techniques such as MRCP, and hCT following an initial transabdominal ultrasound in the assessment of patients with suspected biliary obstruction to select candidates for surgery or therapeutic ERCP. The management of patients with a suspected pancreaticobiliary condition ultimately is dependent on local expertise, availability, cost, and the multidisciplinary collaboration between radiologists, surgeons, and gastroenterologists.

Gallstone disease: Symptoms, diagnosis and endoscopic management of common bile duct stones

Bile duct stones (BDS) are often suspected on history and clinical examination alone but symptoms may be variable ranging from asymptomatic to complications such as biliary colic, pancreatitis, jaundice or cholangitis. The majority of BDS can be diagnosed by transabdominal ultrasound, computed tomography, endoscopic ultrasound or magnetic resonance cholangiography prior to endoscopic or laparoscopic removal. Approximately 90% of BDS can be removed following endoscopic retrograde cholangiography (ERC)+sphincterotomy. Most of the remaining stones can be removed using mechanical lithotripsy. Patients with uncorrected coagulopathies may be treated with ERC+pneumatic dilatation of the sphincter of Oddi. Shockwave lithotripsy (intraductal and extracorporeal) and laser lithotripsy have also been used to fragment large bile duct stones prior to endoscopic removal. The role of medical therapy in treatment of BDS is currently uncertain. This review focuses on the clinical presentation, investigation and current management of BDS.

Role of liver function tests in predicting common bile duct stones in acute calculous cholecystitis

BACKGROUND

The role of liver function tests (LFTs) in evaluating common bile duct (CBD) stones in patients with cholelithiasis has been studied widely. However, it is not clear whether these predictive models are useful in inflammatory gallstone disease.

METHODS

A review was undertaken of 385 consecutive patients admitted as an emergency for acute calculous gallbladder disease. The diagnosis of calculous cholecystitis was confirmed by ultrasonography or histological confirmation of acute or chronic inflammation of the gallbladder. Patients with obvious jaundice, defined as a bilirubin level above 80 micromol/l, and gallstone pancreatitis were excluded.

RESULTS

Some 216 patients met the inclusion criteria, of whom 28 (13.0 per cent) were found to have CBD stones. LFT results were not significantly different in patients with chronic, acute or complicated acute cholecystitis. Using several cut-off levels, gamma-glutamyl transpeptidase (GGT) had the highest specificity, positive predictive value and negative predictive value, comparable to a scoring system that combined all LFTs. Bilirubin was the least specific and predictive. A cut-off point for GGT at 90 units/l produced a sensitivity of 86 per cent (24 of 28), specificity of 74.5 per cent (140 of 188), and positive and negative predictive values of 33 per cent (24 of 72) and 97.2 per cent (140 of 144) respectively. This represented a one in three chance of CBD stones when the GGT level was above 90 units/l and a one in 30 chance when the level was less than 90 units/l.

CONCLUSION

Selection criteria based on GGT can be used in acute calculous cholecystitis to identify high-risk patients who would benefit most from further imaging to exclude choledocholithiasis.

Low incidence of retained common bile duct stones using a selective policy of biliary imaging

AIM

Biliary imaging has decreased since the advent of laparoscopic cholecystectomy. This study aimed to examine the incidence of retained common bile duct (CBD) stones, using a selective policy of biliary imaging.

METHODS

A prospective computerised database was used to study patients who underwent laparoscopic cholecystectomy by one surgeon over 36 months. Two hundred and thirty-five patients (191 female, 44 male) were operated on. Ages ranged from 15 to 82 years (mean 47 years). Follow-up periods ranged from six to 39 months (mean 23.3 months). Selection for pre-operative endoscopic retrograde cholangiopacreatogram (ERCP), intraoperative cholangiography (IOC) or neither depended on liver function tests (LFTs) and CBD diameter on ultrasound prior to surgery. If LFTs were persistently raised and/or the CBD was dilated on ultrasound, patients underwent pre-operative ERCP. If LFTs were raised, and returned to normal promptly, IOC was performed.

RESULTS

Of 235 patients, 26 had pre-operative ERCP, 62 had IOC and 157 had neither. Ten patients had both ERCP and IOC. To date, one patient (0.43%) has radiologically-proven unsuspected retained CBD stones; these were successfully treated with ERCP.

CONCLUSION

Selective biliary imaging in patients undergoing laparoscopic cholecystectomy is safe. This process identifies the majority of patients with ductal calculi and minimises the need for unnecessary ERCP and peroperative cholangiography.

Natural history of asymptomatic bile duct stones at time of cholecystectomy

OBJECTIVES

There is little data on the natural history of asymptomatic bile duct stones and hence there is uncertainty on the management of asymptomatic bile duct stones discovered incidentally at the time of laparoscopic cholecystectomy. We retrospectively reviewed a group of patients who had previously underwent laparoscopic cholecystectomy, but who did not have a pre-operative suspicion of intra-ductal stones, to determine if any biliary complications had subsequently developed. A group of patients who had no pre-operative suspicion of intra-ductal stones, but routinely underwent intraoperative cholangiogram (IOC) at time of cholecystectomy, served as the control group.

METHODS

A telephone questionnaire was completed by each patient's family practitioner in 59 of 79 (75%) patients who underwent laparoscopic cholecystectomy. In the remaining 20 patients additional information was obtained from hospital records and from the central services agency (CSA). These patients had no pre-operative suspicion of bile duct stones and therefore did not undergo an IOC or ERCP. The control group (73 patients) had no pre-operative suspicion of bile duct stones but had a routine IOC performed to define the biliary anatomy.

RESULTS

59 patients were followed up for an average of 57 months (range 30-78 months) after laparoscopic cholecystectomy. None of these patients developed pancreatitis, jaundice, deranged liver function tests (LFT's), or required ERCP or other biliary intervention. In the additional 20 patients where no information was available from the family practitioner, 11 patients had follow up appointments with no documentation of biliary complications or abnormal LFT's. 19 of 20 patients were traceable through the CSA and were all alive. Only 1 patient was untraceable and therefore unknown if biliary complications had developed. In the control group, 4 of 73 (6%) patients had intraductal stones detected and extracted. Thus the prevalence of asymptomatic bile duct stones during the time of cholecystectomy in our population was 6%.

CONCLUSIONS

Asymptomatic bile duct stones discovered at the time of cholecystectomy do not appear to cause any biliary complications over a 5-year follow up. Incidental bile duct stones found in patients undergoing laparoscopic cholecystectomy may not need to be removed.

Preoperative evaluation of common bile duct stones in patients with gallstone disease

OBJECTIVE

Our objective was to suggest criteria for selection of a preoperative diagnostic technique for patients with gallstone disease.

CONCLUSION

Use of MR cholangiography preferentially before laparoscopic cholecystectomy, on patients who have a moderate or high risk of common bile duct stones, can significantly reduce purely diagnostic endoscopic retrograde cholangiography.

Diagnostic criteria in predicting a biliary origin of acute pancreatitis in the era of endoscopic ultrasound: multicentre prospective evaluation of 213 patients

BACKGROUND

No study on bioclinical criteria predicting a biliary origin for acute pancreatitis has included endosonography as a reference examination. Re-examination of bioclinical parameters deserves consideration in the era where other causes are known (e.g. hereditary, autoimmune).

AIM AND METHODS

To determine the performance of bioclinical markers in predicting a biliary origin of acute pancreatitis where the diagnosis of biliary lithiasis was established or ruled out using endosonography. Only patients with a first acute episode of pancreatitis were included.

RESULTS

213 patients (male: 55%; median age: 56 years) were prospectively included in 14 centres. Causes of acute pancreatitis were: biliary (62%), alcoholic (25%), other (13%). Delay between symptom-onset and admission was <48 h in 80%. Endosonography was the sole method establishing the diagnosis of biliary pancreatitis in 15% of patients. At univariate analysis, age, female sex, declared alcohol consumption, elevated aspartate and alanine transaminases on admission, gammaglutamyl transferase, alkaline phosphatase, total bilirubin, lipase, mean corpuscular volume were predictive of a biliary origin. Only age (p < 0.0001), sex (p < 0.0008) and alanine transaminase (p < 0.0004) remained significant at multivariate analysis. At age 50, the respective sensitivity and specificity were 73 and 65%. With an elevated alanine transaminase at 2 times the upper limit of normal range, the respective sensitivity and specificity were 74 and 84%. The probability of a biliary origin of acute pancreatitis could be estimated by the following formula: = 1/1 + exp(4.6967 - 0.0656 x age + 1.1208 x sex - 0.6909 x alanine transaminase).

CONCLUSION

When endosonography is performed to confirm or exclude a biliary origin of acute pancreatitis, age, sex and alanine transaminase at admission are the only factors predictive of a biliary cause.

Predictors of common bile duct lithiasis in laparoscopic era

AIM

To analyze retrospectively the records of 294 consecutive patients operated upon for gallbladder stones, to determine the predictive factors of synchronous common bile duct (CBD) stones and validate prospectively the generated model.

METHODS

The prognostic estimation of a biochemical test and ultrasonography alone to differentiate between the absence and presence of choledocholithiasis was assessed using receiver operating characteristics curve analysis. Multivariate analysis was employed using discriminant analysis for establishment of a best model. Prospective validation of the model was made.

RESULTS

Discriminant forward stepwise analysis disclosed that high values (> or = 2 x normal) of SGOT, ALP, conjugated bilirubin and CBD diameter on ultrasound > or = 10 mm were all prognostic factors of CBD lithiasis in univariate and multivariate analysis, P< 0.01. History was not included in the model. Prospective validation of the model was performed by multivariate analysis using Visual General Stepwise Regression. Positive predictive value, when considering all these predictors, was 93.3%, while the negative predictive value was 88.8%. Sensitivity of the model was 96.5% and specificity 80%.

CONCLUSION

The above model can be objectively applied to predict the presence of CBD stones.

Predição da coledocolitíase pela associação de indicadores clínicos e laboratoriais em dois momentos do pré-operatório da colecistectomia

OBJETIVO: O propósito deste estudo foi determinar a probabilidade de ocorrência de coledocolitíase através do estudo da associação de indicadores clínicos e laboratoriais desta doença em dois momentos do pré-operatório de colecistectomia. MÉTODO: Entre março de 2001 e março de 2002, 48 pacientes consecutivos com colelitíase foram submetidos a colecistectomia e colangiografia intra-operatória (CIO). Os pacientes foram divididos em dois grupos, sendo o grupo A constituído por 13 pacientes com coledocolitíase e o grupo B por 35 pacientes sem esta doença. Os pacientes foram investigados quanto aos indicadores clínicos e laboratoriais da coledocolitíase, analisados em dois períodos, tomando como ponto de corte as 48 horas que precederam a cirurgia. Posteriormente, estes indicadores pré-operatórios foram associados na equação da regressão logística em diferentes combinações. RESULTADOS: Utilizando a equação da regressão logística, constatou-se que a associação de dois indicadores clínicos em ambos os períodos (icterícia e sinal de Murphy) e dois laboratoriais ( nível de corte da gama glutamil transpeptidase e bilirrubina direta 48 horas antes da cirurgia) foi a mais adequada para a predição da coledocolitíase. Os valores obtidos por esta equação mostraram concordância com os grupos A e B, de 95,6%, e discordância de 4,4% (p= 0,0000007 e k = 0,89). Esta equação mostrou sensibilidade de 92,3%, especificidade de 97,0%, valor preditivo positivo de 92,3% e valor preditivo negativo de 97%. Estes valores foram próximos aos obtidos pela CIO, que mostrou concordância com os grupos estudados de 95,8%, e discordância de 4,2% (k = 0,90). CONCLUSÃO: Considerando os resultados obtidos, recomenda-se a associação de indicadores da coledocolitíase na equação da regressão logística para estabelecer a probabilidade de ocorrer coledocolitíase associada à colelitíase. A utilização desta equação pode orientar melhor a conduta diagnóstica e terapêutica nesta doença.

Magnetic resonance cholangiography: applications in patients with calculus disease of the biliary tract

Magnetic resonance cholangiography (MRC) is a non-invasive imaging modality that has become widely available. In the short time since its introduction, MRC has been shown to possess excellent accuracy for the diagnosis of various biliary pathologies, including choledocholithiasis. Investigations of the clinical applications of MRC are ongoing. This review summarizes the diagnostic capabilities of MRC and discusses its application in the management of patients with gallstone diseases.

Diagnosis and management of cholecystitis and cholangitis

Cholelithiasis is a prevalent condition in Western populations. Most cases are asymptomatic but complications can occur. Acute cholangitis, cholecystitis, and gallstone pancreatitis are the most common biliary tract emergencies and are usually caused by biliary calculi. Whenever possible, acute cholecystitis should be treated with early LC. AAC is an uncommon condition usually affecting patients with significant comorbidities. Treatment is usually with percutaneous cholecystostomy, which often is also the only required therapy. Endoscopic drainage is the preferred form of biliary decompression in acute cholangitis and these patients should subsequently undergo elective LC unless unfit for surgery. Effective and optimal management of biliary tract emergencies relies on close cooperation between gastroenterologist, surgeon, and radiologist.

Acute biliary pancreatitis, endoscopy, and laparoscopy

Current practices for diagnosis and treatment of common bile duct stones are not evidence-based. Acute biliary pancreatitis (ABP) is a specific situation in which endoscopic procedures are either overused or misused. Pancreatitis is a poor marker for choledocholithiasis. Prognostic systems are accurate to discern those patients with ABP who do not need aggressive procedures. Patients with a benign ABP do not need an endoscopic approach. Laparoscopic common bile duct exploration is an underrated treatment for patients with choledocholithiasis. Laparoscopic approach to infected necrotic collections and pseudocysts warrant further investigations.

Mathematical model for predicting biliary therapeutic endoscopic retrograde pancreatography (ERCP)

INTRODUCTION

Magnetic resonance cholangiopancreatography is as sensitive as endoscopic retrograde pancreatography in the evaluation of biliary tract diseases but does not offer therapeutic options. The aim of the present study was to develop a mathematical model to predict 'therapeutic endoscopic retrograde pancreatography' using clinical variables so that patients with low probability could be more appropriately investigated by magnetic resonance cholangiopancreatography in future.

METHODS

Endoscopic retrograde pancreatography cases between January 1996 to December 1997 were retrospectively reviewed (before introduction of magnetic resonance cholangiopancreatography). Clinical, biochemical and radiological variables were analysed and a model was developed using multiple logistic regression.

RESULTS

Case notes for 573 patients were successfully reviewed. A total of 330 patients underwent therapeutic endoscopic retrograde pancreatography (sphincterotomy or stent insertion). Clinical indications of obstructive jaundice and cholangitis, ultrasonographic findings of dilated common bile duct, and raised liver function tests (two or more elevated parameters) were each found to be predictive for 'therapeutic' endoscopic retrograde pancreatography. Using these variables, the mathematical model in the present study has specificity of 77% and sensitivity of 75% at the probability level of 50% or higher. This model has been tested in a separate group of endoscopic retrograde pancreatography cases carried out in 1998 and was found to have sensitivity 77.6%, specificity 80.3%, positive predictive value 68.5% and negative predictive value 86.6%.

CONCLUSIONS

The model reported in the present study can help clinicians to identify cases for therapeutic endoscopic retrograde pancreatography and diagnostic magnetic resonance cholangiopancreatography.

Techniques and clinical outcomes of laparoscopic cholecystectomy in adult patients with beta-thalassemias

Beta-thalassemia, which results from a reduced production of beta-globin chain of hemoglobin, is a common single gene disorder with an extremely heterogeneous clinical picture. Its presentation may vary from mild anemia in beta-thalassemia minor to severe and life-threatening anemia in beta-thalassemia major. Recent advances in supportive treatment of beta-thalassemia major have resulted in substantial increase in survival in these patients, and an increasing number of these patients reach adolescence and adulthood. The incidence of cholelithiasis is reported to be increased in these patients. Although laparoscopic cholecystectomy (LC) has become the gold standard treatment of symptomatic gallstone disease, its experience in adult beta-thalassemic patients has been limited. From May 1992 through April 2000, 10 consecutive adult beta-thalassemic patients with symptomatic gallstone underwent LC at our institution. Data were obtained on the type of beta-thalassemia, presentation, preoperative laboratory findings, history of preoperative transfusion, postoperative complications, postoperative analgesic requirement, length of hospital stay, and follow-up. All operations were completed laparoscopically. The mean operative time was 98.5 minutes. The postoperative analgesic requirement was minimal. There was no mortality. One patient developed fever postoperatively due to lung atelectasis that was managed conservatively. The mean hospital stay was 3 days. Laparoscopic cholecystectomy is feasible, safe, and effective in the treatment of adult beta-thalassemic patients with symptomatic gallstone disease. Technical adjustments are required when operating on patients with beta-thalassemia major.

The value of magnetic resonance cholangiopancreatography in predicting common bile duct stones in patients with gallstone disease

BACKGROUND

The application of available predictive scoring systems for the detection of common bile duct (CBD) stones has not reduced the number of patients who undergo unnecessary endoscopic retrograde cholangiopancreatography. The aim of this study was to create a predictive model for CBD stones and to assess the value of magnetic resonance cholangiopancreatography (MRCP) in prediction.

METHODS

In 1998, 366 patients with gallstone disease (118 males, 248 females; mean age 57 (range 8-84) years) underwent cholecystectomy. Statistical analysis was performed on patient data obtained at the time of first presentation.

RESULTS

CBD stones were demonstrated in 43 (12 per cent) of 366 patients. The predictive model for common duct stones included ultrasonography showing CBD stones or bile duct dilatation, age greater than 60 years, fever, serum alkaline phosphatase level above 670 units/l and serum amylase level above 95 units/l. In patients with a predicted probability greater than 5 per cent, CBD stones were present in 11 per cent, compared with 1 per cent in patients with a probability of 5 per cent or less. MRCP had an observed sensitivity of 95 per cent, specificity of 100 per cent, positive predictive value of 100 per cent and negative predictive value of 98 per cent.

CONCLUSION

In patients with a predicted probability for CBD stones of more than 5 per cent, MRCP is recommended in order to confirm the presence or absence of stones and as guidance in further management.

Predicting which patients can undergo upper endoscopy comfortably without conscious sedation

BACKGROUND

Eliminating conscious sedation for diagnostic endoscopy may be advantageous for patient safety and cost containment. The aim of this study was to identify and validate independent predictors of a comfortable, technically adequate, unsedated diagnostic upper endoscopy in Canadian patients.

METHODS

Patients were consecutively enrolled in a prospective fashion. Data collected on an initial cohort of 268 patients included demographics, a validated anxiety questionnaire, use of sedatives/analgesics, upper endoscopy experience, pharyngeal sensitivity, technical adequacy, and patient assessment of comfort after the procedure. The main outcome measure was "satisfactory upper endoscopy," a composite of optimal scores for patient comfort and technical adequacy. Univariate and multivariate analyses were performed to identify the optimal predictive model of a satisfactory unsedated diagnostic upper endoscopy. Once identified, 68 additional patients were enrolled in a similar fashion from an independent prospective sample for purposes of outcome validation. Multivariate analysis was then repeated with the total cohort (N = 336). These results were then compared for concordance with those obtained from the initial cohort.

RESULTS

Among the initial 268 patients (54.3% women; mean age 51 +/- 17 years), 49% were anxious, 15% regularly used sedatives and analgesics, 28% experienced increased pharyngeal sensitivity, and 41% had previously undergone upper endoscopy. Endoscopy was completed in 94.7% of patients without sedation and was technically adequate in 97%, and 80.1% were willing to repeat the procedure under similar conditions. Satisfactory upper endoscopy was achieved in only 59% of the initial cohort. The only independent and significant predictors of a satisfactory upper endoscopy were advancing age (OR 1.2: 95% CI [1.1, 1.4]) and decreased pharyngeal sensitivity (OR 0.5: 95% CI [0.27, 0.93]). Concordance of results were noted after validation with the second cohort. Satisfactory endoscopy was achieved in only 59.5% of the total cohort (n = 336); only 61% reported a comfortable procedural experience.

CONCLUSIONS

The proportion of patients who can comfortably undergo technically adequate unsedated upper endoscopy is modest. Unsedated upper endoscopy is most likely to be successful under these procedural conditions in patients of advancing age with decreased pharyngeal sensitivity. The generalizability of these findings to an American population requires further study and may assist in identifying a subgroup of patients in whom it is cost-effective to perform upper endoscopy comfortably without sedation.

Endoscopic retrograde cholangiopancreatography should no longer be used as a diagnostic test: the case against

Endoscopic retrograde cholangiopancreatography has been used successfully in diagnosis of pancreatico-biliary diseases. Over the past decade, there have been tremendous developments in radiological technologies which have led to the emergence of new and less invasive modalities like endoscopic ultrasound and spiral computed tomography and magnetic resonance cholangiopancreatography. Understandably, the usefulness of diagnostic endoscopic retrograde cholangiopancreatography is being questioned primarily because of its potential attendant complications. Therefore, this controversial question needs to be debated in the gastroenterology community. In this article, we compare the efficacy of newer diagnostic tools with existing "gold standard" modality--endoscopic retrograde cholangiopancreatography, and put forward our arguments in favour of a continuing role for endoscopic retrograde cholangiopancreatography as a diagnostic tool in certain circumstances.

Do patients with recurrent choledocholithiasis after endoscopic sphincterotomy benefit from regular follow-up?

BACKGROUND

As many as 24% of patients who undergo endoscopic sphincterotomy for the removal of bile duct stones have recurrent biliary complications develop for which there is no effective method of prevention. The aim of this study was to determine whether patients who undergo routine clinical follow-up after endoscopic sphincterotomy for bile duct stones have a different outcome than those who do not.

METHODS

All patients who had endoscopic sphincterotomy for bile duct stones were scheduled for follow-up visits, liver function tests, and transabdominal US every 3 to 6 months. ERCP was performed whenever symptoms recurred, or abnormal liver function or US was noted. The patients themselves decided whether to adhere to the follow-up schedule; this was not a randomized trial.

RESULTS

Seven hundred sixty-seven patients underwent endoscopic sphincterotomy for bile duct stones from October 1990 to July 1999. Seventy-seven (10%) were found to have recurrent bile duct stones. Three patients who had undergone Billroth II gastrectomy were excluded. Among the remaining 74 patients (52 men, 22 women; mean age 65 years), 42 (57%) had a juxtapapillary diverticulum and 21 (28%) an intact gallbladder. The mean time to recurrence of bile duct stones was 19.7 months (range 5-72 months). Sixty-four patients (87%) had recurrent bile duct stones within 3 years. Fifty-one (69%) were followed regularly (Group A) and 23 (31%) were not (Group B). At the time of stone recurrence, 20 patients in Group A (39%) and 1 in Group B (4%) were asymptomatic (p = 0.002). Liver function tests were normal in 17 patients (13 Group A, 4 Group B). Endoscopic treatment for recurrent bile duct stones was successful in 46 patients (90%) in Group A and 16 (70%) in Group B (p = 0.04); surgical treatment was successful in all 5 patients in Group A and 4 of the 7 patients in Group B. Two patients in Group B were treated by nasobiliary drainage and biliary endoprosthesis insertion caused by extremely large stones and poor condition; both died (acute pancreatitis and sepsis).

CONCLUSION

Regular follow-up after endoscopic sphincterotomy detects recurrent bile duct stones early and thus avoids complications of bile duct stones.

ERCP's role in the management of acute biliary-pancreatic pathology in the laparoscopic era

OBJECTIVES

Laparoscopic cholecystectomy (LC) combined with endoscopic retrograde cholangiopancreatography (ERCP) has been widely used in the management of the acute biliopancreatic pathology. Nevertheless, controversy remains about the appropriate timing for retrograde cholangiopancreatography.

METHODS

A retrospective study was undertaken on a consecutive series of 117 patients with acute biliary-pancreatic pathology, who underwent laparoscopic cholecystectomy between April 1995 and April 1999. Criteria for preoperative endoscopic retrograde cholangiopancreatography were defined, and the patients were divided into 3 groups based on the presence or absence of a preoperative retrograde cholangiopancreatography indication: (1) ERCP+LC group: patients with retrograde cholangiopancreatography indicated and performed (n = 30); (2) LC group: patients without retrograde cholangiopancreatography criteria treated only by LC (n = 47); (3) LC-ERCP group: patients with retrograde cholangiopancreatography criteria but not performed (n = 40).

RESULTS

The groups were similar in age, sex, ASA, and clinical diagnosis. No statistical differences occurred in operative times (73.8 min, 68 min, 67 min), major complications (3.3%, 4.25%, 12.5%), and mean postoperative stay (3.7 +/- 4; 4.7 +/- 2; 5.7 +/- 2). Postoperative retrograde cholangiopancreatography had to be used, respectively, in 0%, 10.6%, and 7.5%. The best predictive criteria for common bile duct pathology were choledocholithiasis on an ultrasound scan and the presence of cholangitis. The other criteria tested had a low predictive value.

CONCLUSIONS

Preoperative endoscopic retrograde cholangiopancreatography followed by early laparoscopic cholecystectomy can be performed safely in acute biliary-pancreatic pathology, avoiding 2-stage treatment of these patients and minimizing hospital stay and inconvenience to the patients. Nevertheless, this therapeutic/diagnostic tool must be used selectively.

Practical recommendations for the prediction and management of common bile duct stones in patients with gallstones

BACKGROUND

Approximately 10% of patients with symptomatic gallstones may have associated common bile duct stones (CBDS). However, the predictive value of noninvasive tests as well as the preoperative diagnosis and management of CBDS have not been well defined. The aim of this study was to define an accurate and simple model for the prediction and management of CBDS.

METHODS

A prospective database containing 986 cholecystectomies performed from 1994 through 1999 was evaluated. Univariate analysis using the Pearson chi-square test was performed to determine the factors significantly related to the presence of CBDS. Then logistic regression analysis was performed for multivariate analysis to discover independent predictors.

RESULTS

Of the 986 patients in this study, 48 (5%) had CBDS. Of the 48 patients with choledocholithiasis, 22 (46%) were men and 26 (54%) were women. The mean age was 55.3 years (range, 16-87 years). As a result of multivariate analysis, abdominal ultrasonographic findings suggestive of CBDS (common bile duct diameter exceeding 8 mm or visible stones), total bilirubin, and gamma glutamyl transpeptidase levels above normal were the independent predictors of CBDS in patients age 70 or younger. On the other hand, an elevated bilirubin level was found to be the single independent factor related to CBDS in the elderly.

CONCLUSIONS

For patients with gallstones, suggestive ultrasonographic findings in those younger than 71 years and elevated direct or total bilirubin level in those older than 70 years are the most valuable and practical predictors of CBDS, and thus are the proper indications for preoperative endoscopic retrograde cholangiography.

A simple scoring system for predicting bile duct stones in patients with cholelithiasis

A means of accurately predicting the presence of stones in the bile duct in patients undergoing laparoscopic cholecystectomy for gallbladder stones is lacking. With the use of a three-stage analysis, a predictive score was developed from seven common parameters. Initially the score was formulated by using data from a retrospective series of patients undergoing laparoscopic cholecystectomy; the system was then tested prospectively over a 1-year period in patients undergoing laparoscopic cholecystectomy for gallbladder stones. This simple scoring system demonstrated an ability to predict bile duct stones with a sensitivity in excess of 70%. The use of such a score may allow the development of preoperative strategies for treating patients undergoing laparoscopic cholecystectomy.

Patient evaluation and management with selective use of magnetic resonance cholangiography and endoscopic retrograde cholangiopancreatography before laparoscopic cholecystectomy

OBJECTIVE

To assess the utility of triage guidelines for patients with cholelithiasis and suspected choledocholithiasis, incorporating selective use of magnetic resonance cholangiography (MRC) and endoscopic retrograde cholangiopancreatography (ERCP) before laparoscopic cholecystectomy (LC).

SUMMARY BACKGROUND DATA

ERCP is the most frequently used modality for the diagnosis and resolution of choledocholithiasis before LC. MRC has recently emerged as an accurate, noninvasive modality for the detection of choledocholithiasis. However, useful strategies for implementing this diagnostic modality for patient evaluation before LC have not been investigated.

METHODS

During a 16-month period, the authors prospectively evaluated all patients before LC using triage guidelines incorporating patient information obtained from clinical evaluation, serum chemistry analysis, and abdominal ultrasonography. Patients were then assigned to one of four groups based on the level of suspicion for choledocholithiasis (group I, extremely high; group 2, high; group 3, moderate; group 4, low). Group 1 patients underwent ERCP and clearance of common bile duct stones; group 2 patients underwent MRC; group 3 patients underwent LC with intraoperative cholangiography; and group 4 patients underwent LC without intraoperative cholangiography.

RESULTS

Choledocholithiasis was detected in 43 of 440 patients (9.8%). The occurrence of choledocholithiasis among patients in the four groups were 92.6% (25/27), 32.4% (12/37), 3.8% (2/52), and 0.9% (3/324) for groups 1, 2, 3, and 4, respectively (P <.001). MRC was used for 8.4% (37/440) of patients. Patient triage resulted in the identification of common bile duct stones during preoperative ERCP in 92.3% (36/39) of the patients. Unsuspected common bile duct stones occurred in six patients (1.4%).

CONCLUSIONS

The probability of choledocholithiasis can be accurately assessed based on information obtained during the initial noninvasive evaluation. Stratification of risks for choledocholithiasis facilitates patient management with the most appropriate diagnostic studies and interventions, thereby improving patient care and resource utilization.

Endoscopic management of bile duct stones

The advantages of endoscopic retrograde cholangiopancreatography (ERCP) over open surgery make it the predominant method of treating choledocholithiasis. Today, technologic advances such as magnetic resonance cholangiopancreatography and laparoscopic surgery are challenging ERCP's primacy in the management of common bile duct (CBD) stones. This article reviews the current status of endoscopic treatment of biliary stones and examines this in relation to laparoscopic management. The techniques and safety of endoscopic sphincterotomy and balloon sphincteroplasty are reviewed. Balloon sphincteroplasty should be limited to study protocols because of safety questions and inherent limitations. After sphincterotomy, 85% to 90% of CBD stones can be removed with a Dormia basket or balloon catheter. These techniques are described as having both advantages and disadvantages. Methods for managing "difficult stones" include mechanical lithotripsy, intraductal shock wave lithotripsy, extracorporeal shock wave lithotripsy, chemical dissolution, and biliary stenting. These approaches are presented along with data supporting their use in specific situations. Laparoscopic cholecystectomy has emerged as the preferred alternative to open cholecystectomy. Parallel advances in the endoscopic and laparoscopic management of CBD stones have made the issue regarding the optimal treatment strategy complex. Three approaches to the management of choledocholithiasis in the laparoscopic era are presented as follows: strict therapeutic splitting, flexible therapeutic splitting, and strict laparoscopic management. The optimal approach needs to be defined in prospective comparative trials. For now, preoperative endoscopic stone extraction should still be recommended as the approach of choice in patients suspected to have CBD stones based on clinical, biochemical, and imaging parameters. Primary laparoscopic evaluation and management is reasonable in patients who have a low-to-moderate probability of having CBD stones.

Prospective analysis of a scoring system to predict choledocholithiasis

BACKGROUND

The management of choledocholithiasis in the laparoscopic era remains debatable. A common policy is to perform preoperative endoscopic retrograde cholangiopancreatography (ERCP) on patients suspected of having common bile duct (CBD) stones, using standard risk criteria. The aim of this study was to evaluate prospectively a scoring system designed to improve the accuracy of CBD stone prediction before laparoscopic cholecystectomy.

METHODS

Known clinical, biochemical and radiological risk factors for CBD stones were analysed retrospectively in 233 patients. The presence (n = 77) or absence (n = 156) of CBD stones was determined by preoperative ERCP and/or laparoscopic cholangiography. Using multivariate analysis, the significant risk factors for CBD stones were identified and a new preoperative scoring system was developed. A score of 3 or more was taken as the cut-off point to suggest CBD stones and the need for preoperative ERCP. This scoring system was then tested prospectively in 211 consecutive patients with symptomatic gallstones requiring surgery. Patients whose bile ducts could not be demonstrated by ERCP or operative cholangiography were excluded.

RESULTS

Fifty-five patients scored 3 or more (predicted ERCP rate of 29 per cent), of whom 23 (42 per cent) had proven CBD stones. Intraoperative cholangiography was successful in 87 per cent. Five patients (4 per cent) who scored less than 3 had small stones (less than 5 mm) demonstrated at operative cholangiography. The overall sensitivity and specificity of this scoring were 82 and 80 per cent respectively.

CONCLUSION

Formal risk assessment of the presence of CBD stones using this scoring system is simple and may be used for preoperative selection of patients for biliary tract imaging by magnetic resonance cholangiography or ERCP.

Management of Choledocholithiasis in the Era of Laparoscopic Surgery

Laparoscopic biliary surgery is changing the management of choledocholithiasis. Between November 1989 and December 1998, 2834 cholecystectomies were performed at two institutions. Choledocholithiasis was suspected in 420 patients on the basis of elevated preoperative laboratory and ultrasound criteria [bilirubin, alkaline phosphatase, serum glutamic-oxaloacetic transaminase, serum glutamate pyruvate transaminase, and common bile duct (CBD) size]. One hundred seventeen patients had preoperative endoscopic retrograde cholangiopancreatography (ERCP) because of persistent elevation in their enzymes beyond 24 to 48 hours or as an emergency. Laparoscopic intraoperative cholangiogram was attempted in 329 patients whose enzymes fell rapidly within the first 24 to 48 hours or had a failed ERCP. Eighty-one of the 329 were found to have stones. Seventy-three had laparoscopic attempt to clear the CBD, with success in 62 patients (85%). This included 41 transcystic duct and 21 direct CBD exploration. Eight patients had postoperative ERCP for retained stones. Six (0.25%) were in patients with normal preoperative enzymes. We conclude that choledocholithiasis can be suspected with preoperative laboratory and ultrasound criteria. By waiting 24 to 48 hours (except in an emergency), a good number of CBD stones will pass. With increases in laparoscopic experience, laparoscopic removal of CBD stones may replace preoperative ERCP. The small number of cases of retained or missed stones that occur with the use of selective cholangiography can be easily handled with postoperative ERCP.

Role of biliary scintiscan in predicting the need for cholangiography

BACKGROUND

Currently used predictors for bile duct calculi in patients undergoing cholecystectomy have low specificity resulting in unnecessary cholangiograms being performed. The role of biliary scintiscan in predicting the presence of bile duct calculi was assessed.

METHODS

Seventy-five patients with symptomatic gallstone disease were studied prospectively regard- ing the value of a history of jaundice or acute pancreatitis, raised serum bilirubin and serum alkaline phosphatase levels, and visualization of stones or presence of dilated bile ducts on ultrasonography (standard criteria) in detecting bile duct calculi. Results of biliary scintiscan were evaluated against a combination of standard criteria. The 'gold standard' for evaluation was endoscopic or peroperative cholangiography.

RESULTS

Biliary scintiscan had a higher sensitivity and specificity (93 and 94 per cent) than a combination of the above standard and modified predictors for biliary calculi (89 and 71 per cent). A combination of ultrasonography and selective use of scintiscan, in the absence of bile duct dilatation only, had higher values (96 and 98 per cent).

CONCLUSION

A combination of ultrasonography and biliary scintiscan can accurately predict bile duct calculi and could be used as a guide for selective cholangiography.

Choledocholithiasis: a prospective study of spontaneous common bile duct stone migration

BACKGROUND

The rate of spontaneous migration of bile duct stones through the duodenal papilla is not well known. Endoscopic retrograde cholangiography (ERC) has been the standard method to diagnose bile duct stones, but accumulating data show there is a good agreement between ERC and endoscopic ultrasonography (EUS). The aim of the study was to evaluate the incidence and time course of stone migration in patients with bile duct stones by analyzing discrepancies between EUS and ERC as a function of the elapsed time between these two procedures. Stone migration was considered as the absence of stones at time of ERC regardless of the number of stones seen at EUS.

METHODS

The main criterion for inclusion was the presence of bile duct stone as shown by EUS. Ninety-two consecutive patients were prospectively included in this study.

RESULTS

Choledocholithiasis was absent at ERC in 12 patients. In univariate analysis, presence of gallbladder was significantly associated with an increased rate of stone migration (correction for multiple testing would remove this statistical significance). The size of the stone was the only independent factor to predict migration.

CONCLUSION

Migration occurred in about 21% of cases within 1 month. Our study emphasizes the need to analyze carefully the results of comparative imaging studies of bile duct stones.

Preoperative evaluation to predict technical difficulties of laparoscopic cholecystectomy on the basis of histological inflammation findings on resected gallbladder

BACKGROUND

No papers have heretofore documented histological studies of cases involving the inflammation of resected gallbladder or examined surgical difficulties on the basis of pathological findings.

METHODS

On the basis of the histological inflammation findings on the resected gallbladders of 437 patients who underwent laparoscopic cholecystectomy (LC), the factors affecting the technical difficulty of the operation were examined through preoperative clinical findings (13 items), diagnostic imaging (22 items), and blood test findings (6 items), using multivariate analysis.

RESULTS

In accordance with the four-stage classification of inflammation findings for the resected gallbladder, the inflammation findings on the resected gallbladder indicated a higher correlation with the time required for gallbladder dissection (30.2 +/- 16.3 minutes) than with the operation time (77.6 +/- 32.7 minutes). Thus, the technical difficulty of the operation was judged according to the time required for gallbladder dissection. For the preoperative findings on 418 patients who underwent successful LC, the most influential factors on the time required for gallbladder dissection were the presence of abnormal findings on computed tomography, the degree of fever, obesity index, nonvisualized gallbladder cholangiography, and cystic duct length. According to the multiple regression equation of these five factors, the gallbladder dissection for the 19 patients who underwent conversion to open cholecystectomy (OC) due to extreme inflammation was calculated to require 61.9 +/- 12.3 minutes, and the patients who showed a gallbladder dissection time longer than 49.6 minutes were judged to have high technical difficulty predicted from the preoperative evaluation. In the preoperative evaluation, sensitivity was 79.6%, specificity was 97.6%, accuracy was 95.0%, positive predictive value was 85.0%, and negative predictive value was 96.6%. Next, each finding was scored on the basis of a multiple regression equation of five factors, and the technical difficulty of the operation was quantified using these scores. The score of the patients who underwent conversion to OC was 8.0 +/- 2.0, and the patients who showed a score higher than 6 were judged to have high technical difficulty. Almost the same results as in the aforementioned preoperative evaluation were obtained using these scores.

CONCLUSION

The judgment using the scores was satisfactory in terms of the simplicity of evaluating the technical difficulties associated with each patient and the ease of obtaining information for each factor. The quantification of technical difficulty using the scores is useful for preoperative prediction of which patients will have difficulties in gallbladder dissection and the conversion to OC in LC. Our results suggest that the consideration of technical difficulties is important for conducting safe operations with avoiding intraoperative complications.

Diagnostic accuracy of magnetic resonance cholangiopancreatography and ultrasound compared with direct cholangiography in the detection of choledocholithiasis

AIM

To determine the diagnostic accuracy of magnetic resonance cholangiopancreatography (MRCP) and trans-abdominal ultrasound in the detection of choledocholithiasis, and to compare bile duct stone characteristics using endoscopic retrograde cholangiopancreatography (ERCP), MRCP and ultrasound.

MATERIALS AND METHODS

Of 191 consecutive patients referred for diagnostic ERCP, choledocholithiasis was diagnosed in 34 patients using direct cholangiography. The latter took the form of ERCP (n = 29), intraoperative cholangiography (n = 3) or percutaneous transhepatic cholangiography (n = 2). All patients underwent MRCP and ultrasound examinations and their findings for choledocholitiasis were compared with those at direct cholangiography. Finally, in the 29 patients with choledocholithiasis diagnosed under ERCP, stone characteristics were compared across the three investigations of ERCP, MRCP and ultrasound.

RESULTS

Compared with direct cholangiography, MRCP showed a sensitivity, specificity and diagnostic accuracy of 91%, 98% and 97%, respectively, in the diagnosis of choledocholithiasis. MRCP resulted in three false-negative and three false-positive findings, four of which occurred due to confusion with lesions at the ampulla. Ultrasound showed a sensitivity, specificity and diagnostic accuracy of 38%, 100% and 89%, respectively, in the diagnosis of choledocholithiasis. ERCP revealed a greater number of stones and these were more proximally distributed within the bile ducts when compared to MRCP.

CONCLUSIONS

MRCP is highly accurate in the diagnosis of choloedocholithiasis and has the potential to replace diagnostic ERCP. MRCP underestimates the number of bile duct stones present.

The efficacy of preoperative endoscopic retrograde cholangiopancreatography in the detection and clearance of choledocholithiasis

BACKGROUND AND OBJECTIVES

Endoscopic retrograde cholangiopancreaticography has been reported to have a high success rate in the detection and treatment of choledocholithiasis. Although there is growing enthusiasm for laparoscopic common bile duct clearance, many patients who present with gallbladder disease and suspected choledocholithiasis have endoscopic retrograde cholangiopancreatography performed with choledocholithiasis cleared if detected. These patients are then referred for laparoscopic cholecystectomy. The purpose of this study is to determine the efficacy of preoperative endoscopic retrograde cholangiopancreatography in the diagnosis and clearance of bile duct stones at our institution.

METHODS

A retrospective review was performed of all patients at this institution who underwent preoperative endoscopic retrograde cholangiopancreatography for suspected choledocholithiasis followed by laparoscopic cholecystectomy from January 1997 through July 1998.

RESULTS

Common bile duct stones were detected endoscopically in 12 of 17 (71%) patients. We found serum bilirubin level to be the best predictor of choledocholithiasis. In 12 of 12 procedures, the endoscopist performed an endoscopic sphincterotomy with stone extraction and reported a fully cleared common bile duct. Intraoperative cholangiogram performed during subsequent cholecystectomy revealed choledocholithiasis in 4 of these 12 patients. Laparoscopic techniques successfully cleared the choledocholithiasis in 3 of these patients with open techniques necessary in the fourth.

CONCLUSIONS

Our data suggests that even after presumed successful endoscopic clearance of the bile duct stones, many patients (33% in our series) still have choledocholithiasis present at the time of cholecystectomy. We recommend intraoperative cholangiography at the time of cholecystectomy even after presumed successful endoscopic retrograde cholangiopancreatography with further intervention, preferably laparoscopic, to clear the choledocholithiasis as deemed necessary.

Helical computed tomographic cholangiography versus endosonography for suspected bile duct stones: a prospective blinded study in non-jaundiced patients

BACKGROUND

Helical computed tomography performed after intravenous administration of a cholangiographic contrast material (HCT-cholangiography) may be useful for detecting bile duct stones in non-jaundiced patients. However, this method has never been compared with other non-invasive biliary imaging tests.

AIMS

To compare prospectively HCT-cholangiography and endosonography (EUS) in a group of non-jaundiced patients with suspected bile duct stones.

METHODS

Fifty two subjects underwent both HCT-cholangiography and EUS. Endoscopic retrograde cholangiography (ERCP), with or without instrumental bile duct exploration, served as a reference method, and was successful in all but two patients.

RESULTS

Thirty four patients (68%) were found to have choledocholithiasis at ERCP. The sensitivity for HCT-cholangiography in stone detection was 85%, specificity 88%, and accuracy 86%. For EUS the sensitivity was 91%, specificity 100%, and accuracy 94%. The differences were not significant. No serious complications occurred with either method.

CONCLUSIONS

HCT-cholangiography and EUS are safe and comparably accurate methods for detecting bile duct stones in non-jaundiced patients.

The diagnostic accuracy of magnetic resonance cholangiopancreatography and ultrasound compared with direct cholangiography in the detection of choledocholithiasis

AIM

To determine the diagnostic accuracy of magnetic resonance cholangiopancreatography (MRCP) and ultrasound (US) in the diagnosis of choledocholithiasis in a large group of patients with bile duct stones confirmed at direct cholangiography. Also, to compare bile duct stones confirmed at direct cholangiography. Also, to compare bile duct stone characteristics using the three different investigations, endoscopic retrograde cholangiopancreatography (ERCP), MRCP and US.

MATERIALS AND METHODS

191 patients (M:F, 76:115; mean age, 66 years; range, 24-92 years) were investigated by direct cholangiography, MRCP and US. Their final diagnosis as determined at direct cholangiography were choledocholithiasis (n = 34), strictures (n = 47) and normal ducts (n = 110). The direct cholangiographic methods used for diagnosis of choledocholithiasis were ERCP (n = 29), intraoperative cholangiography (n = 3) and percutaneous transhepatic cholangiography (n = 2). The bile duct stone characteristics were compared using ERCP, MRCP and US in the 29 patients in whom stones were exclusively diagnosed by ERCP.

RESULTS

Compared with the final diagnosis, MRCP had a sensitivity, specificity and diagnostic accuracy of 91%, 98% and 97%, respectively, in the diagnosis of choledocholithiasis. MRCP resulted in three false-negative and three false-positive findings, four of which occurred due to confusion with lesions at the ampulla. US had a sensitivity, specificity and diagnostic accuracy of 38%, 100% and 89%, respectively, in the diagnosis of choledocholithiasis. ERCP diagnosed more stones and the stones were more proximally distributed within the bile duct at ERCP when compared with MRCP.

CONCLUSION

MRCP has a high diagnostic accuracy (97%), similar to that at direct cholangiography, in the diagnosis of choloedocholithiasis. It has the potential to replace diagnostic ERCP and select patients with choledocholithiasis for therapeutic ERCP.

Bile duct stones and laparoscopic cholecystectomy: a decision analysis to assess the roles of intraoperative cholangiography, EUS, and ERCP

BACKGROUND

The least costly management strategy for patients undergoing laparoscopic cholecystectomy is unclear.

METHODS

A decision model incorporating cost ratios, test accuracy, complication, and failure rates was used to determine the costs of 4 peri-laparoscopic cholecystectomy strategies: endoscopic retrograde cholangiopancreatography (ERCP), intraoperative cholangiography (IOCG), endoscopic ultrasound (EUS), and expectant management.

RESULTS

Expert IOCG is least costly for intermediate-risk patients when the risk of stones is between 17% and 34%. If expert EUS is available, 0% to 10% ("low" risk) merits expectant management; 11% to 55% ("intermediate" risk) merits EUS; and greater than 55% ("high" risk) merits ERCP. Thresholds were most sensitive to changes in the risks of symptoms and complications due to retained stones; and to procedural costs, sensitivity, and success rates. Neither IOCG nor EUS appears likely to reduce overall costs unless their accuracy and success rates are greater than 90% and their procedural cost is less than 60% to 70% that of ERCP. When neither are available, ERCP is preferable when the risk of stones is greater than 22%. Thresholds were relatively insensitive to changes in the risk and severity of ERCP-induced pancreatitis.

CONCLUSIONS

The least costly strategy for laparoscopic cholecystectomy patients depends primarily on the risk of stones and stone-related symptoms, but procedural costs and operator expertise are also critical.

Prediction of common bile duct stones by noninvasive tests

OBJECTIVE

To define accurate and useful predictors of common bile duct stones (CBDS).

SUMMARY BACKGROUND DATA

The ability to predict CBDS with noninvasive tests can avoid unnecessary, costly, or risky procedures.

METHODS

All patients referred for examination for CBDS by endoscopic ultrasonography (EUS) from 1993-1996 were prospectively entered in a database. In a first sample selected randomly from the whole population, predictors of CBDS were determined by univariate analysis and logistic regression. Predictors were subsequently tested in that sample and in the rest of the population. A separate analysis was done for patients planned for cholecystectomy.

RESULTS

Eight hundred and eighty patients (328 men, 552 women), aged 57.8 +/- 17 years (range 16-94), were included. The prevalence of CBDS was 18.8%. Age, serum levels of bilirubin, aspartate aminotransferase, alanine aminotransferase, gamma-glutamyl transferase (GGT), and alkaline phosphatase, and the existence of jaundice and fever, a dilated bile duct, and a pathologic gallbladder were found to be associated with CBDS. Logistic regression was undertaken separately for patients younger than 70 years (predictors: GGT >7 x normal; pathologic gallbladder; dilated bile duct) and older than 70 years (predictors: GGT >7 x normal; fever > 38 degrees C; dilated bile duct). Odds ratios were 3 to 6.7. The model was satisfactorily applicable to the second sample; age <70 years: chi2 = 3.3 (NS); age >70 years: chi2 = 3.8 (NS). In patients younger than age 70 and planned for cholecystectomy, the combination of the level of GGT and dilated bile duct predicted CBDS accurately.

CONCLUSIONS

A simple screening of patients at risk for CBDS can be achieved with three predictive criteria adapted for the patient's age.

Laparoscopic biliary surgery

Treatment of gallstones by laparoscopic cholecystectomy has become standard therapy over the past decade and has received wide patient acceptance. Problems are infrequent but those such as biliary injury may be serious and continue to be a cause of concern. Biliary injury is more likely when surgery is performed in the presence of acute inflammation. Laparoscopic bile duct exploration is becoming standardized and the results are good. The role of other laparoscopic biliary procedures such as biliary bypass is still uncertain.

The prediction of common bile duct stones using a neural network

BACKGROUND

The role of preoperative ERCP and endoscopic sphincterotomy (ES) in the diagnosis and treatment of suspected common bile duct stones (CBDS) in the laparoscopic age is controversial. The preoperative diagnosis of CBDS by ERCP and the removal of CBDS by ES are advantageous because of technical difficulties in performing laparoscopic exploration of the common bile duct. Approximately 50% of preoperative ERCP examinations are normal, however. The noninvasive diagnosis of CBDS has assumed new importance, but it has proved to be an elusive goal. Neural networks are a form of artificial computer intelligence that have been used successfully to interpret ECGs and to diagnose myocardial infarcts. The purpose of this study was to determine whether a neural network could be trained to predict CBDS accurately in patients at high risk of having duct stones.

STUDY DESIGN

We trained a back-propagation neural network to predict the presence of CBDS. Retrospective data from patients who had a cholecystectomy and either a preoperative ERCP or intraoperative cholangiogram were used to build the network, and it was tested using unseen data.

RESULTS

One hundred forty patients were used to train the network, and 16 patients were used to test it. The trained network was able to predict CBDS in 100% of the patients in both the training and test sets.

CONCLUSIONS

Screening of high-risk patients for CBDS by neural network analysis is highly accurate. This promising new, noninvasive, and inexpensive technique can potentially decrease the need for preoperative ERCP by 50%, but additional prospective evaluation is indicated.

Magnetic resonance cholangiopancreatography accurately predicts the presence or absence of choledocholithiasis

Accurate common bile duct (CBD) imaging in patients with biliary calculi is an important determinant of specific therapy. Noninvasive methods to evaluate calculi in the CBD have limited accuracy and rely mainly on ultrasonography and computed tomography. Magnetic resonance cholangiopancreatography (MRCP) is a new noninvasive modality available to evaluate the biliary system. This study was undertaken to assess the accuracy of MRCP in predicting the presence or absence of CBD stones in patients at increased risk for choledocholithiasis. The medical records of 48 patients with a final diagnosis of biliary calculous disease undergoing MRCP between November 1995 and April 1997 were retrospectively reviewed. Three groups were identified: choledocholithiasis (n = 19), gallstone pancreatitis (n 5 11), and uncomplicated cholelithiasis (n = 18). In all patients the presence or absence of CBD calculi, as determined by MRCP, was correlated with the final diagnosis obtained from endoscopic retrograde cholangiopancreatography (ERCP) (n = 19), intraoperative cholangiography (n = 6), CBD exploration (n = 13), or clinical follow-up (n = 10). Sensitivity, specificity, and accuracy of MRCP were determined. The major clinical indications for MRCP in the 48 patients ware abnormal liver function tests followed by hyperamylasemia. Twenty patients were diagnosed with CBD stones and 28 were not. MRCP correctly predicted the presence of CBD stones in 19 of 20 patients and failed to detect CBD stones in one patient with gallstone pancreatitis. MRCP incorrectly predicted the presence of CBD stones in 3 of 28 patients ultimately found to have gallstones and no CBD stones. MRCP correctly predicted the absence of CBD stones in the other 25 patients including 10 patients with gallstone pancreatitis. Overall, MRCP had a sensitivity of 95%, a specificity of 89%, and an accuracy of 92%. MRCP is an accurate, noninvasive test for evaluating the CBD duct for the presence or absence of calculi in patients suspected of having CBD stones. Our data support the use of MRCP in the preoperative evaluation of these patients as findings may influence therapeutic decisions.

Evolving management of mild-to-moderate gallstone pancreatitis

The objective of this study was to describe recent trends in the management of mild-to-moderate gallstone pancreatitis and assess patient outcomes. Acute gallstone pancreatitis has traditionally been managed with open cholecystectomy and intraoperative cholangiography during the initial hospitalization. The popularization of endoscopic retrograde cholangiopancreatography (ERCP) and laparoscopic cholecystectomy has made a reassessment necessary. Two consecutive time periods were retrospectively analyzed: prior to laparoscopic cholecystectomy (prelaparoscopic era [PLE]) and after the diffusion of laparoscopic cholecystectomy (laparoscopic cholectomy era [LCE]). There were 35 patients in the PLE group and 58 in the LCE group. LCE patients waited 37.1 +/- 63 days from admission until cholecystectomy, compared to 9.8 +/- 14.8 days in the PLE group (P = 0.04). Biliary-pancreatic complications occurred in 24% of LCE patients and only 6% of PLE patients (P = 0.05), nearly always while they were awaiting cholecystectomy (P = 0.009). Patients in either time period who underwent cholecystectomy with intraoperative cholangiography developed less pancreatic-biliary complications than those who underwent ERCP prior to cholecystectomy, with or without sphincterotomy. Delaying the interval from pancreatitis to laparoscopic cholecystectomy beyond historical values is associated with a greater risk of recurrent biliary-pancreatic complications, which are not prevented by the use of ERCP. Early cholecys tectomy with intraoperative ductal evaluation is still the approach of choice.