Jeffrey L. Tokar

Temporary placement of covered self-expandable metal stents in benign biliary strictures: a new paradigm? (with video)

BACKGROUND Benign biliary strictures (BBS) are usually managed with plastic stents, whereas placement of uncovered metallic stents has been associated with failure related to mucosal hyperplasia. OBJECTIVE We analyzed the efficacy and safety of temporary placement of a covered self-expanding metal stent (CSEMS) in BBS. DESIGN Patients with BBS received temporary placement of CSEMSs until adequate drainage was achieved; confirmed by resolution of symptoms, normalization of liver function tests, and imaging. SETTING Tertiary-care center with long-standing experience with CSEMSs. PATIENTS Seventy-nine patients with BBS secondary to chronic pancreatitis (32), calculi (24), liver transplant (16), postoperative biliary repair (3), autoimmune pancreatitis (3), and primary sclerosing cholangitis (1). INTERVENTION ERCP with temporary CSEMS placement. Removal of CSEMSs was performed with a snare or a rat-tooth forceps. MAIN OUTCOME MEASUREMENTS End points were efficacy, morbidity, and clinical response. RESULTS CSEMSs were removed from 65 patients. Resolution of the BBS was confirmed in 59 of 65 patients (90%) after a median follow-up of 12 months after removal (range 3-26 months). If patients who were lost to follow-up, developed cancer, or expired were considered failures, then an intent-to-treat global success rate of 59 of 79 (75%) was obtained. Complications associated with placement included 3 post-ERCP pancreatitis (4%), 1 postsphincterotomy bleed (1%), and 2 pain that required CSEMS removal (2%). In 11 patients (14%), the CSEMS migrated. In 1 patient, CSEMS removal was complicated by a bile leak that was successfully managed with plastic stents. LIMITATION Pilot study from a single center. CONCLUSIONS Temporary CSEMS placement in patients with BBS offers a potential alternative to surgery.

Efficacy and complications of covered wallstents in malignant distal biliary obstruction

BACKGROUND This study evaluated the efficacy and the complications associated with the use of the covered Wallstent in the setting of unresectable malignant biliary obstruction. METHODS Between March 2001 and January 2003, all patients with distal malignant biliary obstruction that required drainage were treated with a covered Wallstent. Every 2 months, the patients were evaluated clinically and biochemical tests of liver function were obtained. Data were recorded for the following variables: early complications (within 30 days of stent placement), early and late stent occlusion, duration of stent patency, need for subsequent biliary intervention, and patient survival. RESULTS A total of 88 covered Wallstents were inserted in 80 patients. Stent patency rates at 3, 6, and 12 months were 90%, 82%, and 78%, respectively. Complications included stent migration (5), stent occlusion (12), episodes of cholecystitis (3), and episodes of post-ERCP pancreatitis (5). Biliary intervention was required in 9 patients subsequent to placement of the initial covered Wallstent. CONCLUSIONS Deployment of a covered Wallstent is safe and relatively easy. It achieves biliary drainage with an acceptable risk to benefit ratio in the majority of patients with distal malignant biliary obstruction.

Wireless capsule endoscopy

Over the last decade, WCE has established itself as a valuable test for imaging the small intestine. It is a safe and relatively easy procedure to perform that can provide valuable information in the diagnosis of small-bowel conditions. Its applications still remain limited within the esophagus and colon. Future developments may include improving visualization within the esophagus and developing technologies that may allow manipulation of the capsule within the GI tract and biopsy capabilities.

Use of an over-the-scope clipping device: multicenter retrospective results of the first U.S. experience (with videos)

y t w f O c p t Through-the-scope (TTS) clipping devices have been available for nearly 20 years, and applications include the treatment of GI bleeding, closure of perforations and fistulae, and anchoring of feeding tubes. Although these evices are relatively inexpensive and easy to use, they ave limited opening widths and closing strengths and are sually ineffective in the setting of fibrotic tissue. Recently, publications emerged demonstrating the feaibility and use of a novel over-the-scope clip (OTSC) evice.5 Experimental studies have demonstrated the abilty of the OTSC to close perforations6-8 and control arterial leeding.9 Comparative animal trials have shown the sueriority of OTSCs relative to TTS clips for closure of erforations10,11 and natural orifice transluminal endoscopic surgery (NOTES) access points.12-14 Subsequent case reports and small case series in humans have shown great promise of the device for the treatment of arterial bleeding and for the closure of endoscopic perforations and fistulae.15,16 The largest series published to date comrises 50 patients.17 All of these studies have emanated

Complications associated with double balloon enteroscopy at nine US centers.

BACKGROUND & AIMS Double balloon enteroscopy (DBE) was introduced into the US in 2004. Potential complications include perforation, pancreatitis, and gastrointestinal bleeding. Prevalence and risk factors for complications have not been described in a US population. METHODS We conducted a retrospective study of DBE complications in 9 US centers. We obtained detailed information for each complication including patient history, maneuvers performed during the DBE, and presence of altered surgical anatomy. RESULTS We collected data from 2478 DBE examinations performed from 2004 to 2008. The dataset included 1691 (68%) anterograde DBE, 722 (29%) retrograde DBE (including 5 per-stomal DBEs), and 65 (3%) DBE-facilitated endoscopic retrograde cholangiopancreatography ERCP cases. There were a total of 22 (0.9%) major complications including perforation in 11 (0.4%), pancreatitis in 6 (0.2%), and bleeding in 4 (0.2%) patients. One of 6 cases of pancreatitis occurred post retrograde DBE. Perforations occurred in 3/1691 (0.2%) anterograde examinations and 8/719 (1.1%) retrograde DBEs (P = .004). Eight (73%) perforations occurred during diagnostic DBE examinations. Four of 8 retrograde DBE perforations occurred in patients with prior ileoanal or ileocolonic anastomoses. In the subset of 219 examinations performed in patients with surgically altered anatomy, perforations occurred in 7 (3%), including 1/159 (0.6%) anterograde DBE examinations, 6/60 (10%) retrograde DBEs, and 1 of 5 (20%) peristomal DBE examinations (P < .005 compared with patients without surgically altered anatomy). CONCLUSIONS DBE is associated with a higher complication rate compared with standard endoscopic procedures. The perforation rate was significantly elevated in patients with altered surgical anatomy undergoing diagnostic retrograde DBE examinations.

EUS-guided transhepatic cholangiography: report of 6 cases

BACKGROUND This report describes a novel application of EUS-guided cholangiography in which a transhepatic approach was used to alleviate perihilar and distal biliary obstructions when this could not be accomplished at ERCP. METHODS EUS-guided transhepatic cholangiography was used to alleviate symptoms of biliary obstruction in 6 patients. In 4 cases, after transgastric puncture of an intrahepatic branch of the obstructed bile duct with a 19- or a 22-gauge EUS needle, a guidewire was advanced antegrade across both the biliary stricture and the papilla. Subsequently, a rendezvous procedure was performed, allowing ERCP and stent placement. OBSERVATIONS EUS-guided transhepatic cholangiography was performed in 6 patients, with successful rendezvous ERCP and stent placement in 4, and transduodenal stent placement in another patient. Stent placement was unsuccessful in one patient, because of the inability to advance a guidewire into the common hepatic duct. There was no immediate complication of the procedures. CONCLUSIONS EUS-guided transhepatic cholangiography can be used to access and to drain bile ducts that are obstructed by proximal, as well as distal lesions when ERCP is unsuccessful.

Factors predictive of malignancy and Endoscopic resectability in ampullary neoplasia

OBJECTIVE:Endoscopic treatment of ampullary lesions has been well described, though it remains uncertain if specific features predict malignancy, and whether identifiable factors are associated with successful endoscopic resection of benign lesions.METHODS:Fifty-six consecutive patients undergoing endoscopic evaluation of ampullary neoplasia between March 2000 and May 2004 were included in the study. Clinical presentation, underlying medical conditions, endoscopic treatment, endoscopic ultrasound (EUS) to define extent of local involvement, pathology results, and outcome were documented. Data elements for analysis included EUS findings, lesion lifting with submucosal injection, age, gender, tumor size, and endoscopic intervention. Analyses were performed to determine the ability to predict malignancy and the ability to extirpate benign lesions.RESULTS:Thirty-one males and 25 females were included; mean age was 62 yr. Final diagnoses included 29 adenomas, 20 adenocarcinomas, 4 adenomyomas, 2 paragangliomas, and 1 neuroendocrine tumor. Thirty of 35 patients with benign lesions had extirpation with a mean of two endoscopic procedures. Complications of endoscopic resection included cholangitis (1), bleeding (2), and pancreatitis (4). The presence of malignancy was associated by multivariate analysis with the inability to obtain a cleavage plane with saline injection. Univariate analysis also identified EUS T stage as a predictor of malignancy. In benign lesions, none of the analyzed variables predicted successful endoscopic resection.CONCLUSION:In ampullary lesions, failure to achieve a cleavage plane with submucosal injection is the strongest predictor of malignancy followed by EUS T stage. Endoscopic treatment of benign ampullary neoplasia is effective; no factor was predictive of successful extirpation.

Proteomic Analyses of Pancreatic Cyst Fluids

Objectives: There are currently no diagnostic indicators that are consistently reliable, obtainable, and conclusive for diagnosing and risk-stratifying pancreatic cysts. Proteomic analyses were performed to explore pancreatic cyst fluids to yield effective diagnostic biomarkers. Methods: We have prospectively recruited 20 research participants and prepared their pancreatic cyst fluids specifically for proteomic analyses. Proteomic approaches applied were as follows: (1) matrix-assisted laser-desorption-ionization time-of-flight mass spectrometry peptidomics with LC/MS/MS (HPLC-tandem mass spectrometry) protein identification; (2) 2-dimensional gel electrophoresis; (3) GeLC/MS/MS (tryptic digestion of proteins fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and identified by LC/MS/MS). Results: Sequencing of more than 350 free peptides showed that exopeptidase activities rendered peptidomics of cyst fluids unreliable; protein nicking by proteases in the cyst fluids produced hundreds of protein spots from the major proteins, making 2-dimensional gel proteomics unmanageable; GeLC/MS/MS revealed a panel of potential biomarker proteins that correlated with carcinoembryonic antigen (CEA). Conclusions: Two homologs of amylase, solubilized molecules of 4 mucins, 4 solubilized CEA-related cell adhesion molecules (CEACAMs), and 4 S100 homologs may be candidate biomarkers to facilitate future pancreatic cyst diagnosis and risk-stratification. This approach required less than 40 &mgr;L of cyst fluid per sample, offering the possibility to analyze cysts smaller than 1 cm in diameter.

Tissue adhesives: cyanoacrylate glue and fibrin sealant

The ASGE Technology Committee provides reviews of existing, new, or emerging endoscopic technologies that have an impact on the practice of GI endoscopy. Evidence-based methodology is used, performing a MEDLINE literature search to identify pertinent clinical studies on the topic and a MAUDE (U.S. Food and Drug Administration Center for Devices and Radiological Health) database search to identify the reported adverse events of a given technology. Both are supplemented by accessing the “related articles” feature of PubMed and by scrutinizing pertinent references cited by the identified studies. Controlled clinical trials are emphasized, but in many cases, data from randomized, controlled trials are lacking. In such cases, large case series, preliminary clinical studies, and expert opinions are used. Technical data are gathered from traditional and Web-based publications, proprietary publications, and informal communications with pertinent vendors. Technology Status Evaluation Reports are drafted by 1 or 2 members of the ASGE Technology Committee, reviewed and edited by the Committee as a whole, and approved by the Governing Board of the ASGE. When financial guidance is indicated, the most recent coding data and list prices at the time of publication are provided. For this review, the MEDLINE database was searched through August 2012 for relevant articles by using the key words cyanoacrylate, cyanoacrylate glue, cyanoacrylate and gastroenterology, cyanoacrylate and endoscopy, fibrin glue, fibrin sealant, tissue glue and endoscopy. Technology Status Evaluation Reports are scientific reviews provided solely for educational and informational purposes. Technology Status Evaluation Reports are not rules and should not be construed as establishing a legal standard of care or as encouraging, advocating, requiring, or discouraging any particular treatment or payment for such treatment.

Prospective evaluation of pancreatic sphincterotomy as a precut technique for biliary cannulation

BACKGROUND & AIMS Pancreatic sphincterotomy has been described as an effective technique to obtain biliary access after standard methods fail. This prospective study evaluates its efficacy and compares its complication rate to conventional biliary sphincterotomy (BS). METHODS Between January 2001 and January 2004, patients in whom biliary cannulation failed underwent a pancreatic precut sphincterotomy (PPS) and were analyzed prospectively. Multivariate analysis was performed on the following variables with regard to their ability to predict successful biliary cannulation: age, gender, time to access bile duct after precut (< or =10 or >10 minutes), final diagnosis, and operator. Complications of PPS were then compared with those resulting from endoscopic retrograde cholangiopancreatography with BS in 120 patients examined during the same period of time and matched by sex, gender, and disease process. RESULTS One hundred sixteen patients (50 male), mean age 58 +/- 16 years, underwent PPS. Immediate biliary access was achieved after pancreatic precut in 99 cases (85%). Complications occurred in 14 patients (12%): 3 (2.6%) postsphincterotomy bleeding, 9 (8%) pancreatitis (8 mild, 1 moderate), and 2 (1.7%) retroperitoneal perforation managed conservatively. The factor statistically associated with successful biliary cannulation was the amount of elapsed time between completing the PPS and obtaining biliary access. No statistical difference was identified in the complication rate of pancreatitis between the PPS and BS groups. CONCLUSIONS PPS is an effective precut technique to facilitate biliary cannulation. Success is correlated to the speed of biliary access after precut. In expert hands, its rate of pancreatitis is similar to endoscopic retrograde cholangiopancreatography with BS.