Dirk Domagk

Single- vs. double-balloon enteroscopy in small-bowel diagnostics: a randomized multicenter trial

BACKGROUND AND STUDY AIMS Double-balloon enteroscopy (DBE) is the first choice endoscopic technique for small-bowel visualization. However, preparation and handling of the double-balloon enteroscope is complex. Recently, a single-balloon enteroscopy (SBE) system has been introduced as being a simplified, less-complex balloon-assisted enteroscopy system. PATIENTS AND METHODS This study was a randomized international multicenter trial comparing two balloon-assisted enteroscopy systems: DBE vs. SBE. Consecutive patients referred for balloon-assisted enteroscopy were randomized to either DBE or SBE. Patients were blinded with regard to the type of instrument used. The primary study outcome was oral insertion depth. Secondary outcomes included complete small-bowel visualization, anal insertion depth, patient discomfort, and adverse events. Patient discomfort during and after the procedure was scored using a visual analog scale. RESULTS A total of 130 patients were included over 12 months: 65 with DBE and 65 with the SBE technique. Patient and procedure characteristics were comparable between the two groups. Mean oral intubation depth was 253 cm with DBE and 258 cm with SBE, showing noninferiority of SBE vs. DBE. Complete visualization of the small bowel was achieved in 18 % and 11 % of procedures in the DBE and SBE groups, respectively. Mean anal intubation depth was 107 cm in the DBE group and 118 cm in the SBE group. Diagnostic yield and mean pain scores during and after the procedures were similar in the two groups. No adverse events were observed during or after the examinations. CONCLUSIONS This head-to-head comparison study shows that DBE and SBE have a comparable performance and diagnostic yield for evaluation of the small bowel.

Endoscopic Retrograde Cholangiopancreatography, Intraductal Ultrasonography, and Magnetic Resonance Cholangiopancreatography in Bile Duct Strictures: A Prospective Comparison of Imaging Diagnostics with Histopathological Correlation

OBJECTIVES:A variety of imaging techniques are available to diagnose bile duct strictures; the most effective imaging technique, however, has not been established yet. In the present study, we compared the impact of endoscopic retrograde cholangiopancreatography (ERCP), intraductal ultrasonography (IDUS), and magnetic resonance cholangiopancreatography (MRCP) with regard to diagnosing bile duct strictures.METHODS:We prospectively examined 33 patients with jaundice due to bile duct strictures by ERCP plus IDUS and MRCP. The objectives were to assess diagnostic quality of imaging, complete presentation of the bile duct, and differentiation of malignant from benign lesions. Surgical and histopathological correlations, which were used as the gold standard, were available in all cases since all included patients underwent laparotomy.RESULTS:Diagnostic image quality for ERCP was 88% and 76% for MRCP (p > 0.05). Comparing ERCP and MRCP, complete presentation of the biliary tract was achieved in 94% and 82%, respectively (p > 0.05). ERCP and MRCP allowed correct differentiation of malignant from benign lesions in 76% and 58% (p = 0.057), respectively. By supplementing ERCP with IDUS, the accuracy of correct differentiation of malignant from benign lesions increased significantly to 88% (p = 0.0047).CONCLUSIONS:Comparing ERCP with MRCP, we found adequate presentation of bile duct strictures in high imaging quality for both techniques. ERCP supplemented by IDUS gives more reliable and precise information about differentiation of malignant and benign lesions than MRCP alone without additional imaging sequences.

Endoscopic transpapillary biopsies and intraductal ultrasonography in the diagnostics of bile duct strictures: a prospective study.

Background: In bile duct strictures, examination of wall layers by intraductal ultrasonography (IDUS) performed during endoscopic retrograde cholangiopancreatography (ERCP) may be diagnostically useful. Methods: In the present study 60 patients with bile duct strictures of unknown aetiology were examined preoperatively by ERCP, including transpapillary biopsies and IDUS. Histopathological correlation was available for all patients undergoing these procedures. Results: Postoperative diagnosis revealed 30 pancreatic carcinomas, 17 bile duct cancers, three gall bladder cancers, and 10 benign bile duct strictures. Using endoscopic transpapillary forceps biopsies (ETP), a correct preoperative diagnosis was achieved in 36 of 60 patients (60% of cases). Among the 50 malignant tumours, preoperative diagnosis by ETP revealed a sensitivity of 52% and a specificity of 100%. ERCP supplemented by IDUS allowed for correct preoperative diagnosis in 83% of cases (50 of 60 patients), which was significantly higher than the accuracy of ETP (p=0.008). By combining ETP with IDUS, a correct preoperative diagnosis was made in 59 of 60 patients resulting in an accuracy rate of 98%. Conclusions: Because of its low accuracy, exclusive use of ETP is not a reliable diagnostic tool for a definitive preoperative diagnosis of bile duct strictures. By combining IDUS and ETP with ERCP however, preoperative diagnostic accuracy can be improved substantially.

Double Balloon Enteroscopy: A Useful Tool for Diagnostic and Therapeutic Procedures in the Pancreaticobiliary System

OBJECTIVES:Diagnostic and therapeutic interventions in the biliary and pancreatic system in the previously operated patient by conventional endoscopic retrograde cholangiopancreaticography (ERCP) are difficult and, depending on the surgical procedure, in many cases unsuccessful. We describe our experience of ERCP performed with a double balloon enteroscope (DBE) as an alternative examination technique for these patients.METHODS:In a retrospective analysis of all DBE procedures at our department between November 2004 and June 2007, 11 patients were identified with various anatomic variations in whom ERCP was performed using a DBE.RESULTS:In 72% of the patients, previous conventional ERCP examinations failed (8/11). In these patients, DBE-ERCP was successful in 63%. The overall success rate of DBE-ERCP in all patients was 64% (7/11 patients). In those patients, interventions such as papillotomy, calculus extractions, as well as stent placement could be performed even though tools for DBE-ERCP are still very limited. Despite most of the DBE-ERCPs having included therapeutic interventions, no major complications occurred in our case series and minor side effects were restricted to meteorism and mild to moderate abdominal pain.CONCLUSIONS:DBE-ERCP is an alternative method for diagnostic as well as therapeutic interventions in the biliary as well pancreatic system in the operated patient. However, it should be limited to selected patients, e.g., with contraindications for PTC, as it is a time-consuming as well as a cost-intensive procedure.

Performance measures for lower gastrointestinal endoscopy: a European Society of Gastrointestinal Endoscopy (ESGE) Quality Improvement Initiative

The European Society of Gastrointestinal Endoscopy (ESGE) and United European Gastroenterology (UEG) have identified quality of endoscopy as a major priority and we described our rationale for this in a first manuscript that also addressed the methodology of the quality initiative process.1 The identification of upper gastrointestinal (UGI) performance measures presents a considerable challenge, in contrast to the situation with colonoscopy for instance, where several performance measures (inspection time, adenoma detection rate, and interval cancers, among others) have been identified over the last decade.2,3 Following the Quality in UGI Endoscopy meeting held in Lisbon in 2013, it was clear that there was a need to identify performance measures for the UGI tract, and that quality standards could be identified although there is a paucity of evidence. This lack of evidence helps however to identify research priorities for the development of clinical trials that will further validate and substantiate the implementation of performance measures. The aim therefore of the UGI working group was twofold: (a) to identify performance measures for UGI endoscopy; (b) to identify the evidence or absence of evidence that would develop the research priorities in this field. We used an innovative methodology to facilitate the quality initiative process, which combined a thorough search and standardized evaluation of the available evidence for each clinical question, followed by a Delphi process (http://is.njit.edu/pubs/delphibook/delphibook.pdf) using an online platform.4,5 This online platform permitted iterative rounds of modification and comment by all members of the UGI working group until agreement was reached on the performance measure. We now report these newly identified performance measures.

Quantitative Stain-Free and Continuous Multimodal Monitoring of Wound Healing In Vitro with Digital Holographic Microscopy

Impaired epithelial wound healing has significant pathophysiological implications in several conditions including gastrointestinal ulcers, anastomotic leakage and venous or diabetic skin ulcers. Promising drug candidates for accelerating wound closure are commonly evaluated in in vitro wound assays. However, staining procedures and discontinuous monitoring are major drawbacks hampering accurate assessment of wound assays. We therefore investigated digital holographic microscopy (DHM) to appropriately monitor wound healing in vitro and secondly, to provide multimodal quantitative information on morphological and functional cell alterations as well as on motility changes upon cytokine stimulation. Wound closure as reflected by proliferation and migration of Caco-2 cells in wound healing assays was studied and assessed in time-lapse series for 40 h in the presence of stimulating epidermal growth factor (EGF) and inhibiting mitomycin c. Therefore, digital holograms were recorded continuously every thirty minutes. Morphological changes including cell thickness, dry mass and tissue density were analyzed by data from quantitative digital holographic phase microscopy. Stimulation of Caco-2 cells with EGF or mitomycin c resulted in significant morphological changes during wound healing compared to control cells. In conclusion, DHM allows accurate, stain-free and continuous multimodal quantitative monitoring of wound healing in vitro and could be a promising new technique for assessment of wound healing.

Teaching ultrasound in a curricular course according to certified EFSUMB standards during undergraduate medical education: a prospective study

BackgroundAs a non-invasive and readily available diagnostic tool, ultrasound is one of the most important imaging techniques in medicine. Ultrasound is usually trained during residency preferable according to German Society of Ultrasound in Medicine (DEGUM) standards. Our curriculum calls for undergraduate training in ultrasound of medical students in their 4th year of undergraduate education. An explorative pilot study evaluated the acceptance of this teaching method, and compared it to other practical activities in medical education at Muenster University.Methods240 medical students in their 4th year of undergraduate medical education participated in the training and completed a pre- and post-questionnaire for self-assessment of technical knowledge, self-assurance of the procedure, and motivation in performing ultrasound using a Likert scale. Moreover, students were asked about their interest in pursuing a career in internal medicine. To compare this training to other educational activities a standardized online evaluation tool was used. A direct observation of procedural skills assessment (DOPS) for the first time applied on ultrasound aimed to independently assess the success of our teaching method.ResultsThere was a significant increase in technical knowledge and self-assurance (p < 0.001) of the students’ self-assessments. The clinical relevance and self-motivation of the teaching were evaluated positively. The students’ DOPS results demonstrated proficiency in the understanding of anatomic structures shown in ultrasonographic images, including terminology, machine settings, and transducer frequencies.ConclusionsTraining ultrasound according to certified DEGUM standards was successful and should be offered in undergraduate medical education. The evaluation of the course affirmed the necessity, quality and clinical relevance of the course with a top ranking score of hands-on training courses within the educational activities of the Medical Faculty of Muenster.

Prevalence, associations, and trends of biliary-tract candidiasis: a prospective observational study

BACKGROUND Biliary obstruction and cholangitis are common problems in gastroenterology. Infections of the biliary tract with Candida and other fungal species have increasingly been seen in the last few years. OBJECTIVE To investigate the prevalence, associations, and trends of biliary-tract candidiasis. DESIGN A prospective, observational, diagnostic study. SETTING University Hospital, Muenster, Germany. PATIENTS Consecutive patients undergoing ERCP for various indications. RESULTS In 54 of 123 patients, we found Candida species in bile samples (44%). In only 7 patients, candidiasis was suspected on endoscopy before mycologic proof. Only 4 of these 7 patients were correctly diagnosed with biliary candidiasis by simple morphologic aspects. The fungus was mainly differentiated as Candida albicans or Candida glabrata and rarely as Candida parapsilosis, Candida tropicalis, or other subspecies. Immunosuppression for various reasons was significantly associated with bile-duct candidiasis (P < .02). No significant association was found between positive fungal cultures and prior endoscopic sphincterotomy (P = .0824) or prior ERCP (P = .1152). Biliary candidiasis was neither associated with positive fungal cultures of buccal smears (P = .0722) nor with positive findings in stool samples (P = .0860). LIMITATIONS Highly selected patient population. Buccal smears and stool samples were not obtained from all patients. Contamination artifacts cannot totally be excluded with the ERCP procedure. CONCLUSIONS Candida species very frequently can be detected in the bile. Positive fungal cultures of bile samples are not just contamination artifacts. This has to be taken into account when designing an anti-infectious treatment for recurrent cholangitis or even more cholangiosepsis. Especially in immunosuppressed patients or recipients of long-term antibiotic therapy, physicians should screen for biliary-tract candidiasis during endoscopic examination.

Pancreatic cystic lesions: The value of contrast-enhanced endoscopic ultrasound to influence the clinical pathway.

Background and Objectives: Cystic pancreatic lesions are a growing diagnostic challenge. The aim of this study was to proof a new diagnostic concept based on contrast-enhanced endoscopic ultrasound (CE-EUS) for differential diagnosis. Patients and Methods: A total of 125 patients with unclear cystic pancreatic lesions were included. The initial diagnostic was made by CE-EUS dividing the lesions in a group without contrast enhancing effect in the cystic wall, septae or nodule indicating pseudocysts or dysontogenetic cysts and a group with contrast enhancing effect in the described structures indicating cystic neoplasias. The investigations were performed using a Pentax echoendoscope and Hitachi Preirus ultrasound machine. The contrast enhancer used was 4.8 mL SonoVue® (Bracco, Italy). The group with suspected cystic neoplasia was referred for endoscopic fine-needle puncture for further diagnostic or treatment decisions. Results: The dividing of the groups by contrast-enhanced ultrasound was feasible because all (n = 56) suspected cystic neoplasias showed a contrast enhancing effect, whereas in only 4 from 69 pseudocystic or dysontogenetic cystic lesions a contrast enhancing effect in the wall could be observed. Endoscopic fine-needle puncture could diagnose all malignant neoplasias and relevant premalignant conditions. The long-term follow-up did not show any development of malignant cystic lesions. Conclusion: Using CE-EUS and endoscopic fine-needle puncture as diagnostic criteria seemed to be a feasible method to deal with different cystic lesions in daily practice.

Diagnostic and radiological management of cystic pancreatic lesions: Important features for radiologists

Cystic pancreatic neoplasms are often an incidental finding, the frequency of which is increasing. The understanding of such lesions has increased in recent years, but the numerous types of lesions involved can hinder differential diagnosis. They include, in particular, intraductal papillary mucinous neoplasms (IPMN), serous cystic neoplasms (SCN), and mucinous cystic neoplasms (MCN). Knowledge of their histological and radiological structure, as well as distribution in terms of localization, age, and sex, helps to differentiate such tumours from common pancreatic pseudocysts. Several types of cystic pancreatic neoplasms can undergo malignant transformation and, therefore, require differentiated radiological management. This review aims to develop a broader understanding of the pathological and radiological characteristics of cystic pancreatic neoplasms, and provide a guideline for everyday practice based on current concepts in the radiological management of the given lesions.