Opportunity costs of gastrointestinal endoscopic training in Canada.

BACKGROUND: No data exist to define the opportunity costs related to instruction in endoscopic procedures in Royal College of Physicians and Surgeons of Canada-accredited teaching centres. Academic and institutional administrators expect staff to achieve acceptable performance standards. There is a need to measure some of the effects of training activity in the establishment of such standards. OBJECTIVE: To measure the effect of resident training in colonoscopy on real procedure times and, as a secondary goal, to estimate procedural losses related to the process of training. METHODS: Real procedure times for ambulatory colonoscopy in a single academic, hospital-based endoscopy unit were documented. Times for certified endoscopy instructors functioning solo were compared with times for procedures involving trainees at several levels of colonoscopic experience. Procedural reductions associated with resident training were estimated based on the parameters derived from the results. The analysis was executed retrospectively using prospectively collected data. RESULTS: Resident training prolonged procedure times for ambulatory colonoscopy by 50%. The trainee effect was consistent, although variable in degree, among a variety of endoscopy instructors. Such increased procedure times have the potential to reduce case throughput and endoscopist remuneration. CONCLUSIONS: Resident training in colonoscopy in a Canadian certified training program has significant negative effects on case throughput and endoscopist billings. These factors should be considered in any assessment of performance in similar training environments.

Intraductal optical coherence tomography during endoscopic retrograde cholangiopancreatography for investigation of biliary strictures.

BACKGROUND AND STUDY AIMS: Optical coherence tomography (OCT) uses infrared light reflectance to produce high-resolution cross-sectional tissue images. The aim of this study was to demonstrate the feasibility of biliary intraductal OCT during endoscopic retrograde cholangiopancreatography (ERCP) and to assess the potential of the method to detect malignant biliary strictures. PATIENTS AND METHODS: Thirty-seven patients with biliary strictures were studied during therapeutic ERCP. Malignant strictures were defined as those that demonstrated malignant cells in brushing and/or biopsy specimens, and/or endoscopic ultrasound-guided fine-needle aspiration and/or surgery. Strictures that did not have malignant cells in resected specimens and were without clinical/radiological evidence of disease progression for at least a 12-month follow-up period were considered as benign. Two OCT criteria for malignancy were considered: unrecognizable layer architecture; and presence of large, nonreflective areas compatible with tumor vessels. Sensitivity and specificity for brushings/biopsies as well as OCT criteria were calculated. RESULTS: Nineteen patients had malignant and 16 had benign strictures. In two patients, OCT assessment could not be performed due to tight strictures. Malignancy was confirmed by biliary brushings/biopsies in 12/19 (63 %) patients. OCT revealed that two malignancy criteria were encountered in 10/19 (53 %) and at least one criterion in 15/19 (79 %) patients with malignant strictures. No patient with benign stricture met both criteria and 5/16 met one criterion (31 %). Combining brushings/biopsy with the observation of at least one OCT criterion resulted in the diagnosis of malignancy in 16/19 (84 %) patients. CONCLUSIONS: OCT may improve the sensitivity and diagnostic accuracy of biliary brushings/biopsies alone.

Liver biopsies for chronic hepatitis C: should nonultrasound-guided biopsies be abandoned?

BACKGROUND/OBJECTIVE: Liver biopsy has been the gold standard for grading and staging chronic hepatitis C virus (HCV)- mediated liver injury. Traditionally, this has been performed by trained practitioners using a nonimage-guided percutaneous technique at the bedside. Recent literature suggests an expanding role for radiologists in obtaining biopsies using an ultrasound (US)-guided technique. The present study was undertaken study to determine if the two techniques produced liver biopsy specimens of similar quality and hypothesized that at our institution, non-US-guided percutaneous liver biopsies for HCV would be of higher quality than US-guided specimens. METHODS: Liver biopsies from 100 patients with chronic HCV infection (50 consecutive US-guided and 50 consecutive non-US-guided), were retrospectively identified using a hospital histopathology database. All original biopsy slides were coded and prospectively reanalyzed by a single hepatopathologist who was blinded to the technique used in obtaining the biopsy. Additionally, all liver biopsies for chronic HCV infection completed at the centre from 1998 to 2007 were identified and the technique used was recorded. Biopsy quality was determined primarily by the number of complete portal tracts (CPTs) identifiable in the slides. The total length of specimen and the degree of fragmentation were secondary outcome measures. RESULTS: There was a slight difference observed between the US-guided and non-US-guided groups in mean age (46.3 years versus 42.5 years, respectively; P=0.018) but no differences in sex, presence of cirrhosis, bilirubin, creatinine, international normalized ratio, and grade or stage of disease. Biopsies obtained using the US-guided technique produced higher quality specimens than the non-US-guided technique based on our primary outcome of number of CPTs in the biopsy (11.8 versus 7.4; P<0.001). US-guided specimens also were longer (24.4 mm versus 19.7 mm; P=0.001), had less fragmentation (P=0.016), and a higher overall histopathological quality assessment (P=0.026) than the non-US-guided biopsies. However, there was no significant difference between the two groups in the ability to grade and stage the disease (96% US-guided versus 90% in non-US-guided (P=0.20). Over a 10-year period, 763 biopsies for chronic HCV infection were identified with an obvious trend toward the increased use of US-guided technique observed at 2% in 1998 to 85% in 2007. CONCLUSIONS: US-guided liver biopsies for chronic HCV are the most common method of obtaining specimens at the Kingston General Hospital, Kingston, Ontario, and are of higher quality than non-US-guided specimens. However, there is no significant difference in the two techniques in the ability to grade and stage chronic HCV.

A reliable and safe gastrotomy closure technique assessed in a porcine survival model pilot study: success of the Queen's closure.

BACKGROUND AND STUDY AIMS: The evolution of NOTES to clinical implementation has been hampered by lack of a reliable, safe, and easy-to-implement technique for closure of the opening created in accessing the peritoneum. The Queen's closure uses a combination of endoscopic clips and loop devices to seal such defects in the stomach wall. This study aimed to assess the Queen's closure in a porcine survival model. METHODS: Five 30-kg pigs underwent endoscopic transgastric surgery with exploration of the peritoneum. The endoscope was then withdrawn back into the stomach and the closure performed. The animals were recovered, monitored closely, and underwent endoscopy 1 week after surgery. They were then euthanized at 2 (n = 2) and 3 (n = 3) weeks after surgery with subsequent necropsy. RESULTS: The mean procedure time (from intubation of the esophagus to withdrawal of the endoscope) was 79 minutes (range 45-105 minutes) with a mean time of exploration of the peritoneum of 14 minutes (range 8-25 minutes). All animals recovered well with no apparent pain, distress, or signs of infection. Endoscopic examination 1 week after surgery revealed all the closures to be intact and only identifiable by a small ulcer. At necropsy, the gastrotomy site was identifiable only by minor serosal adhesions. Histological study demonstrated full-thickness closure with minimal inflammation. CONCLUSIONS: The Queen's closure is a reliable and safe technique that provides full-thickness gastrotomy closure without any observed complications. The technique has proven to be transferable knowledge that holds promise for clinical implementation.

The Queen's closure: a novel technique for closure of endoscopic gastrotomy for natural-orifice transluminal endoscopic surgery.

BACKGROUND AND AIMS: Finding a reliable, safe, adaptable method of closing gastrotomies for natural-orifice transluminal endoscopic surgery (NOTES) procedures has been a major challenge facing this new clinical area. The Queen's NOTES Group has designed a novel endoscopic method of closing gastrotomies which involved using PolyLoop polyp ligature devices and endoscopic clips. The current study describes the technique and a pilot study of leak testing it versus hand-sewn suture closure. METHODS: Ten fresh pig stomachs were used, five for each technique. A 16-mm endoscopic gastrotomy was performed on the anterior wall of each. Five stomachs were then closed using the Queen's closure technique, and five with a hand-sewn double-layer suture technique. The stomachs were then connected to a water infusion device with sensitive pressure monitoring and were filled until leakage was detected at the closure site. RESULTS: The closures were all technically successful. The mean time for each gastrotomy and closure using the Queen's closure technique was 1.2 hours. The mean leak pressure for the Queen's closure was 51.8 mmHg and for the hand-sewn suture technique it was 80.8 mmHg ( P < 0.001). CONCLUSIONS: The Queen's closure technique holds promise as a reliable transferable technique for closing gastrotomies. Further study is necessary to evaluate its effects in live models.

Nonsurgical management of severe esophageal and gastric injury following alkali ingestion.

The ingestion of caustic substances may result in significant gastrointestinal injury. Endoscopy can play a major role in the initial evaluation and subsequent therapy of such injuries. The case of a 50-year-old man who ingested an alkaline floor stripper is described, including the endoscopic management of esophageal and pyloric strictures, with good functional results. The role of endoscopy, steroids and acid suppression in the management of such patients is also explored.

Risk factors for pancreatitis after pancreatic sphincterotomy: a review of 572 cases.

BACKGROUND AND STUDY AIMS: Endoscopic pancreatic sphincterotomy is indispensable for many therapeutic endoscopic maneuvers, but is also associated with a higher risk of pancreatitis after endoscopic retrograde cholangiopancreatography (ERCP). In this study, this subgroup of patients was investigated in order to identify risk factors and protective factors. PATIENTS AND METHODS: A retrospective chart review identified 572 endoscopic pancreatic sphincterotomies that met the inclusion criteria. Charts were examined for indications, endoscopic technique, and outcomes, including pancreatitis. RESULTS: A total of 477 patients underwent 572 endoscopic pancreatic sphincterotomies during a 5-year period. Indications for sphincterotomy included chronic pancreatitis (n = 398), access for tissue sampling (n = 52), acute recurrent pancreatitis (n = 45), transpapillary drainage of a pancreatic pseudocyst (n = 32), precut access to the common bile duct (n = 29), and others (n = 16). Pancreatic duct drainage was performed in 69.1 % of the procedures (nasopancreatic catheter, n = 290, or pancreatic stent placement, n = 105). Post-ERCP pancreatitis occurred in 69 cases (12.1 %) and was severe in 10. The multivariate analysis identified female sex as being associated with a higher risk of pancreatitis, while an elevated C-reactive protein level, pancreatic ductal stones, sphincterotomy at only the major papilla, and pancreatic duct drainage with a nasopancreatic catheter or stent were associated with a lower risk. CONCLUSIONS: This large series of patients undergoing endoscopic pancreatic sphincterotomy provides further evidence that both patient characteristics and technical factors modify the risk profile for post-ERCP pancreatitis. In addition to providing further definition of which patients are at risk, it also suggests that pancreatic duct drainage is an independently significant protective maneuver.

Endoscopic ultrasound elastography: the first step towards virtual biopsy? Preliminary results in 49 patients.

BACKGROUND AND STUDY AIMS: It is well known that some diseases, such as cancer, lead to changes in the hardness of tissue. Sonoelastography, a technique that allows the elasticity of tissue to be assessed during ultrasound examination, provides the ultrasonographer with important additional information that can be used for diagnosis. The aim of this study was to evaluate the ability of endoscopic ultrasound elastography to differentiate between benign and malignant pancreatic masses and lymph nodes. PATIENTS AND METHODS: During a 12-month period, 49 patients underwent endoscopic ultrasound (EUS) examinations with elastography, conducted by a single endoscopist. Twenty-four patients underwent evaluation of a pancreatic mass (mean diameter 24.7 +/- 11.1 mm) and 25 underwent evaluation of 31 lymph nodes. The mean diameter of the lymph nodes was 19.7 +/- 8.6 mm, and they were found in the cervical area (n = 3), mediastinum (n = 17), celiac arterial trunk region (n = 5), and aortocaval region (n = 6). RESULTS: The sonoelastography images of pancreatic masses were interpreted as benign in four cases and malignant in 20. The sensitivity and specificity of sonoelastography in the diagnosis of malignant lesions were 100% and 67%, respectively. The sonoelastography images of the lymph nodes were interpreted as showing malignancy in 22 cases, benign conditions in seven, and indeterminate status in two. The sensitivity and specificity of sonoelastography for evaluating malignant lymph-node invasion were 100% and 50%, respectively. CONCLUSIONS: EUS elastography is potentially capable of further defining the tissue characteristics of benign and malignant lesions but specifity has to be improved. It can be used to guide biopsy sampling for diagnosis.

The treatment of patients with symptomatic common bile duct stenosis secondary to chronic pancreatitis using partially covered metal stents: a pilot study.

BACKGROUND AND STUDY AIMS: Although surgery remains the gold standard for the treatment of symptomatic common bile duct stenosis associated with chronic pancreatitis, plastic and self-expandable open-mesh stents have been proposed as alternative treatments. These may dysfunction, however, mainly due to stent occlusion by clogging or by hyperplasia of inflammatory tissue. The aim of this study was to evaluate the safety and long-term results of using partially covered metal stents in this setting. PATIENTS AND METHODS: A total of 14 patients (12 men, 2 women; mean age 50 +/- 3 years) underwent partially covered metal stent insertion for common bile duct stenosis secondary to chronic pancreatitis (12 alcohol-related, two idiopathic). They had all been treated previously with plastic prostheses. RESULTS: Either a 40-mm (n = 13) or a 60-mm (n = 1) partially covered metal stent was placed, depending on the length of the common bile duct stenosis and the level of the cystic duct bifurcation. Stent placement was successful, with resolution of cholangitis and improvement in cholestasis, in all patients. During the median follow-up period of 22 months (range 12 - 33 months) seven patients developed dysfunction of the stent and required re-treatment. At 12, 24, and 30 months, the stent patency rates were 100 %, 40 %, and 37.5 % respectively. CONCLUSIONS: While partially covered metal stenting is safe and effective for the initial treatment of chronic pancreatitis-associated common bile duct stenosis and shows promising short-term results, long-term data show that dysfunction occurs in 50 % of cases. In light of the continued interest in nonsurgical treatment of this condition, further research is warranted to investigate new stent designs with improved long-term patency.

Long-term outcome after pancreatic stenting in severe chronic pancreatitis.

BACKGROUND AND STUDY AIMS: Although it has been proved that pancreatic stenting is effective in the symptomatic management of severe chronic pancreatitis, long-term outcomes after stent removal have not been fully evaluated. PATIENTS AND METHODS: A total of 100 patients (75 men, 25 women; median age 49) with severe chronic pancreatitis and pancreatic duct strictures were successfully treated for pancreatic pain using polyethylene pancreatic stents and were followed up for at least 1 year after stent removal. The stents were exchanged "on demand" (in cases of recurrence of pain) and a definitive stent removal was attempted on the basis of clinical and endoscopic findings. Clinical variables were retrospectively assessed as potential predictors of re-stenting. RESULTS: The etiology of the chronic pancreatitis was alcoholic (77 %), idiopathic (18 %), or hereditary (5 %). Patients were followed up for a median period of 69 months (range 14 - 163 months) after study entry, including a median period of 27 months (range 12 - 126 months) after stent removal. The median duration of pancreatic stenting before stent removal was 23 months (range 2 - 134 months). After attempted definitive stent removal, 30 patients (30 %) required re-stenting within the first year of follow-up, at a median time of 5.5 months after stent removal (range 1 - 12 months), while in 70 patients (70 %) pain control remained adequate during that period. By the end of the follow-up period a total of 38 patients had required re-stenting and four ultimately underwent pancreaticojejunostomy. Pancreas divisum was the only factor significantly associated with a higher risk of re-stenting (P = 0.002). CONCLUSIONS: The majority (70 %) of patients with severe chronic pancreatitis who respond to pancreatic stenting maintain this response after definitive stent removal. However, a significantly higher re-stenting rate was observed in patients with chronic pancreatitis and pancreas divisum.

6-mercaptopurine and inflammatory bowel disease: hidden ground for the cytomegalovirus.

6-mercaptopurine (6-MP) and azathioprine are important drugs for the treatment of inflammatory bowel disease (IBD) but their actions suppress host defense against infection. A challenging case of a 19-year-old female patient with quiescent Crohn's disease maintained with 6-MP presenting with dyspnea and a normal chest exam and x-ray is presented. She became ventilator-dependent and only after numerous investigations was diagnosed with cytomegalovirus (CMV) pneumonitis. A systematic literature review of CMV infections in IBD patients was performed. The present case is the first report of a patient with quiescent IBD maintained on 6-MP who developed CMV pneumonitis. Other reports have identified patients with active disease on multiple immunosuppressants who developed CMV pneumonitis and also highlight the risk of CMV colitis in refractory IBD. The authors review the approach to the diagnosis of CMV infections in IBD patients with atypical pneumonia and colitis and highlight the importance of considering CMV infection in these settings.