Incidence and risk factors for biliary and pancreatic stent migration

Endoprostheses are commonly used in the treatment of biliary and pancreatic disorders. The frequency of and potential risk factors for stent migration, however, remain largely unknown. From January 1986 to June 1990, 807 biliary and pancreatic stents were placed at our institution. Our study analyzed the occurrence of stent migration among the 589 stents for which follow-up data were available. Results demonstrated incidence rates of 4.9 and 5.9% for proximal (into the duct) and distal (out of the duct) biliary stent migration, respectively. Likewise, incidence rates of 5.2 and 7.5% were observed for proximal and distal pancreatic stent migration, respectively. Malignant strictures, larger diameter stents, and shorter stents were significantly associated with proximal biliary stent migration. Sphincter of Oddi dysfunction and longer stents were associated with proximal pancreatic stent migration. Migration of stents out of the common bile duct occurred more frequently in papillary stenosis. No other significant risk factors for distal migration were found. These results indicate that stent migration is an important complication. Multiple risk factors were associated with stent migration and need to be considered in the development of new stent types.

Treatment of pancreatic pseudocysts with ductal communication by transpapillary pancreatic duct endoprosthesis

BACKGROUND

Endoscopic treatment of pancreatic pseudocysts via cystenterostomy has been recognized as a successful treatment option in carefully selected patients. Pancreatic transpapillary stenting as an alternative treatment option in patients with pancreatic pseudocysts directly communicating with the main duct has received little consideration. The aim of the current study was to assess the safety and utility of transpapillary pancreatic endoprosthesis in the treatment of communicating pseudocysts.

METHODS

Twenty-one patients underwent placement of 33 transpapillary endoprostheses for the treatment of symptomatic pancreatic pseudocysts. All pseudocysts communicated with the main pancreatic duct and ranged in size from 3 to 9 cm (mean 6 cm). Eight patients had associated pancreatic duct strictures.

RESULTS

Stent placement was successful in all cases: 13 directly into the pseudocyst, 8 beyond the stricture but not into the pseudocyst. Initial resolution of pseudocysts was seen in 17 patients, with 16 patients free of pseudocyst recurrence at mean follow-up of 37 months. All patients with associated strictures were treated successfully. Factors predictive of success included presence of strictures, size of pseudocyst greater than or equal to 6 cm, location in the body of the pancreas, and duration of pseudocyst less than 6 months. Complications included one episode of mild pancreatitis.

CONCLUSIONS

Endoscopic treatment of symptomatic pancreatic pseudocysts with ductal communication by transpapillary pancreatic duct stenting is a safe, effective modality and should be considered a first line therapy.

Endoscopic retrograde brush cytology. A new technique

Endoscopic retrograde cholangiopancreatography has been shown to be a very valuable adjunct in the diagnosis of malignancy involving the biliary and/or pancreatic ductal system. However, characteristic endoscopic retrograde cholangiopancreatography radiographic findings associated with malignant strictures are frequently not specific and cytological confirmation becomes essential for the diagnosis. Unfortunately, the current overall diagnostic yield of positive cytology in such circumstances ranges from 18%-56% depending on the technique. A new brush device has been designed which is uniquely adapted to pancreaticobiliary strictures of varying anatomical configurations. This study shows results using this new cytology brush in a series of 53 patients with pancreaticobiliary malignancy. A significant improvement in the cytological yield of tumor confirmation was obtained with a diagnostic sensitivity of 70% and specificity of 100% using the new brush technique.

Endoscopic treatment of biliary tract strictures in sclerosing cholangitis: a larger series and recommendations for treatment

We report a group of 35 patients with primary sclerosing cholangitis who had long-term follow-up after endoscopic treatment of major ductal strictures in the primary or secondary biliary ducts. Our patients were all symptomatic with ascending cholangitis or jaundice. There was significant improvement as measured by clinical parameters of hospitalization rates and laboratory data and comparable radiography. Long-term follow-up averaged 24 (+/- 2.8 months). We believe endoscopic treatment of sclerosing cholangitis should be attempted in selected symptomatic cases with major ductal strictures before liver transplantation.

Endoscopic retrieval of proximally migrated biliary and pancreatic stents: experience of a large referral center

BACKGROUND

Proximal migration of a biliary or pancreatic stent is an infrequent event but its management can be technically challenging.

METHODS

Review of all cases of proximally migrated biliary and pancreatic stents over a 10-year period at a referral pancreatic-biliary center. Data abstracted from patient records included indication for stenting, method of presentation, success of attempt, and method used. Successful methods were determined by reviewing procedure reports. Follow-up was attempted in all patients in whom stent retrieval had failed.

RESULTS

Thirty-three proximally migrated bile duct stents, and 26 proximally migrated pancreatic duct stents were identified. Most of the patients were without symptoms. Eighty-five percent of common bile duct stents and 80% of pancreatic duct stents were successfully extracted endoscopically. Seventy-one percent (34 of 48) were retrieved with a basket or balloon. Of the stents not retrieved, two patients did not return for repeat ERCP, three patients with malignant common bile duct strictures were managed with placement of a second stent, three patients with pancreatic duct stents have remained without symptoms with no further retrieval attempts, and three patients with proximally migrated pancreatic duct stents required surgery because of pain and failure of multiple endoscopic retrieval attempts.

CONCLUSION

Over 80% of proximally migrated bile duct and pancreatic duct stents may be extracted endoscopically. Few patients will require surgery.

Treatment of non-extractable common bile duct stones with combination ursodeoxycholic acid plus endoprostheses

Despite widely available technology for removal of bile duct stones, endoscopists currently encounter approximately 3% of patients with stones that defy extraction. After sphincterotomy and unsuccessful attempts at extraction of "defiant" stones, biliary stents were placed in 22 patients. Ten patients were treated with ursodeoxycholic acid, and 12 patients treated only with stent served as control subjects. Ductal strictures preventing stone extraction were present in eight control patients and in six patients treated with ursodeoxycholic acid. The number of total calculi in the ursodeoxycholic acid group was slightly higher (4.2 per patient) than the number in the control group (3.3 per patient). Stone and bile duct dimensions were similar in each group. Nine of 10 patients in the ursodeoxycholic acid group had complete stone clearance, and 41 of 42 stones were removed during a follow-up period of 9 +/- 2 months; in contrast, no patient in the control group had complete clearance and only 6 of 40 stones were removed after a follow-up period of 31 +/- 6 months. Oral ursodeoxycholic acid facilitates extraction of defiant bile duct stones. This treatment is an effective alternative to high-tech extraction methods for large biliary stones.

The role of surveillance endoscopic retrograde cholangiopancreatography in preventing episodic cholangitis in patients with recurrent common bile duct stones

BACKGROUND AND STUDY AIMS

Approximately 2-7% of patients who have undergone previous removal of bile duct stones have recurrence often presenting as ascending cholangitis. The aim of this study was to identify the incidence, clinical presentation, and objective findings in this group of patients. Additionally, the effect of surveillance endoscopic retrograde cholangiopancreatography (ERCP) in preventing cholangitis, was studied.

PATIENTS AND METHODS

Two thousand and ninety-six patients who underwent ERCP for cholelithiasis were studied with 45 of these patients being identified as having recurrent common bile duct stones. Of the 45, 13 had two or more recurrences without having any obvious predisposing factors. The mean age of the 13 patients was 57 years. The characteristics of 13 patients were reviewed, including sphincterotomy size, liver function tests, and contrast drainage time.

RESULTS

All 13 patients with recurrent stones presented with ascending cholangitis. Stones were found to be soft, brown and accompanied by a large amount of sludge. The common bile duct in all 13 patients was noted to be dilated and had notable, widely patent sphincterotomes. There was significant delayed drainage in 77% of these patients. Yearly surveillance ERCPs were performed in the 13 patients, the incidence of acute cholangitis episodes per patient decreased from 2 to 0.6 with a four-year follow-up.

CONCLUSION

In a subgroup of patients with multiple common bile duct stone recurrences, annual surveillance ERCP with stone removal decreases the incidence of recurrent episodes of ascending cholangitis as well as its associated morbidity and mortality.

Endoscopic treatment of problems encountered after laparoscopic cholecystectomy [corrected]

With the advent of laparoscopic cholecystectomy, a number of patients with various postprocedure problems have been referred for endoscopic management. Thirty-five patients were evaluated. The group included 26 women and 9 men, ages 24 to 90 years (mean, 50 years). Twenty-five patients with retained common bile duct stones were successfully treated with endoscopic sphincterotomy and balloon or basket removal. Three patients with bile duct strictures had balloon dilation and endoprosthesis placement and were free of signs of obstruction on 9-month follow-up. Bile leaks were treated successfully with endoscopic sphincterotomy and endoprosthesis placement. Two patients with bile duct leaks and biloma formation required percutaneous or surgical drainage in addition to endoscopic treatment. Three patients had more than one complication. Two patients had strictures with retained stones above the stricture; dilation of the stricture was performed and the stones were removed. One patient with the complication of biliary leak and a long, irregular stricture was treated temporarily by sphincterotomy and stent placement while awaiting surgery. Therapeutic biliary endoscopy is a valuable, minimally invasive alternative to surgery in patients with problems arising after laparoscopic cholecystectomy.

The incidence of post-sphincterotomy stenosis in group II patients with sphincter of Oddi dysfunction

Patients with group II sphincter of Oddi dysfunction documented by elevated sphincter of Oddi pressure improve after endoscopic sphincterotomy. A large group II population was studied to determine the incidence of post-endoscopic sphincterotomy stenosis. Eighty-five patients (82 women and 3 men), ages 21 to 88 years (mean, 50 years), fulfilled the clinical criteria for group II sphincter of Oddi dysfunction; each had an elevated basal sphincter of Oddi pressure (> or = 40 mm Hg), and received endoscopic sphincterotomy. These patients were observed for a mean of 7 +/- 3 years. Four patients re-presented with clinical findings suggestive of recurrent sphincter of Oddi dysfunction; all were found to have a basal sphincter of Oddi pressure greater than or equal to 40 mm Hg. Symptoms re-developed within 4 months after endoscopic sphincterotomy (mean, 3.3 months). Endoscopic sphincterotomy was repeated in all four patients with one endoscopically treated complication. On 25-month mean follow-up, none of the patients had further signs or symptoms of papillary stenosis. Endoscopic sphincterotomy in patients with group II sphincter of Oddi dysfunction is associated with a low incidence of restenosis (4.7%). Repeat endoscopic sphincterotomy was found to be effective management in patients with papillary restenosis.

Guidewire fracture during endoscopic sphincterotomy

Aberrant current conductance during an endoscopic sphincterotomy is a potential hazard. However, such complications have remained primarily theoretical. In this case report, we describe the fracture of a 0.018" Teflon-coated guidewire while performing a sphincterotomy with a 7 French, dual-chambered papillotome. The fractured guidewire was free and loose in the biliary tree, but was subsequently retrieved with endoscopic techniques. Inspection of the papillotome revealed charring of the plastic area adjacent to the cutting wire tip. The electrocautery unit was found to be in normal operating condition after formal testing. We speculate that the papillotome was defective, allowing current flow directly from the cutting wire to the guidewire. The small diameter guidewire then allowed a greater current density, resulting in heat which eventually contributed to fracture of the guidewire. Aberrant current can be conducted over a non-insulated guidewire. This potential hazard can be avoided with an insulated (coated) guidewire or removal of a non-insulated guidewire.

Therapeutic pancreatic endoscopy

Therapeutic endoscopic retrograde cholangiopancreatography (ERCP) has established itself as a valuable tool for the treatment of a variety of biliary tract disorders. Fueled by an ever-increasing demand for minimally invasive therapy, pancreatic endoscopy was the logical frontier for expansion of therapeutic ERCP. Endoscopic treatment of benign pancreatic disorders can be a cost-effective alternative to more invasive radiological or surgical methods. Conditions such as acute and chronic pancreatitis, pancreatic calculi, and pseudocysts can in many cases be managed endoscopically. This review summarizes the current state of the art in therapeutic pancreatic endoscopy.

Pain on common bile duct injection during ERCP: does it indicate sphincter of Oddi dysfunction?

The reproduction of a patient's biliary-type pain upon initial injection of contrast material into the common bile duct during diagnostic ERCP is a dramatic experience for both patient and physician. The significance of this phenomenon is not clear, but it is touted by some to be a provocative test for sphincter of Oddi dysfunction. Sphincter of Oddi manometry was performed on 224 consecutive patients referred over a 2-year period for evaluation of post-cholecystectomy syndrome and suspected sphincter of Oddi dysfunction. All patients received only intravenous diazepam as premedication for ERCP. Delayed drainage time (greater than 45 min), bile duct dilation (greater than or equal to 12 mm), and a basal sphincter of Oddi pressure of greater than 40 mm Hg (mean +/- 3 SD) were considered elevated. We observed a reproduction of pain in 15 of 224 patients (6.7%) immediately following contrast injection. There was no correlation between pain on contrast injection and elevated basal sphincter of Oddi pressure, delayed common bile duct drainage, bile duct dilation, or abnormal liver enzymes. Therefore, we feel that reproduction of the patient's biliary-type pain associated with contrast injection of ERCP is not a provocative test for sphincter of Oddi dysfunction.

Filling defects in the pancreatic duct on endoscopic retrograde pancreatography

Filling defects in the pancreatic duct are a frequent finding during endoscopic retrograde pancreatography (ERP) and have a variety of causes. Some filling defects may be artifactual or related to technical factors and, once their origin is recognized, can be disregarded. Others may be due to acute changes of pancreatitis and should prompt more careful injection of contrast material into the duct. Intraluminal masses may represent calculi or a neoplasm, either of which may require surgery or endoscopic intervention. The exact nature of these filling defects may not be apparent on radiographs, and other studies may be needed. This article reviews our approach to the evaluation of filling defects in the pancreatic duct.