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Jürgen F Riemann

Publications and source records attributed to Jürgen F Riemann.

At least 19 recordsLinked to original sources
PubMed2006

Computer-assisted colonoscopy (the NeoGuide Endoscopy System): results of the first human clinical trial ("PACE study").

OBJECTIVES: Unsedated colonoscopy is an uncomfortable procedure for most patients. Discomfort during colonoscopy is largely related to looping of the colonoscope, which displaces the colon from its native configuration and stretches attachments to the mesentery. A novel computer-assisted colonoscope utilizes a fully articulated, computer-controlled insertion tube. On manual insertion of the colonoscope, the position and angle of the scope's tip are encoded into a computer algorithm. As the colonoscope is advanced, the computer directs each successive segment to take the same shape that the tip had at a given insertion depth. The insertion tube thus changes its shape at different insertion depths in a "follow-the-leader" manner. METHODS: This initial clinical trial with this novel colonoscopy system was designed as a prospective, nonrandomized, unblinded, feasibility study. Three physicians of varying levels of experience participated in the study. RESULTS: Eleven consecutive patients (seven men, four women, age range 19-80) meeting inclusion criteria for screening or diagnostic colonoscopy were enrolled in the study. The cecum was reached in 10 consecutive patients (100%). Findings included diverticular disease in two cases and multiple colonic polyps in two cases. Postprocedure assessment at discharge, 48 h, and 30 days revealed no complications or adverse effects. Physician satisfaction and patient acceptance of this new technique were high. CONCLUSIONS: In this limited, first of its kind feasibility study, the computer-assisted colonoscope was shown to perform colonoscopy safely and effectively. The colonoscope's unique design limited loop formation during colonoscopy. Large-scale clinical trials are indicated.

Adult↗
PubMed2006

Accuracy of high-resolution chromoendoscopy in prediction of histologic findings in diminutive lesions of the rectosigmoid.

BACKGROUND: The ability to differentiate adenomatous from nonadenomatous colonic polyps by using chromoendoscopy would obviate the need to remove hyperplastic lesions. The aim of this study was to define the accuracy of high-resolution chromoendoscopy for the determination of colonic polyp histology. METHODS: In 158 patients, 273 polyps (<5 mm) in the rectosigmoid were estimated for their histology. The endoscopists, in two steps, predicted the histopathology of each lesion on the basis of its surface characteristics by using high-resolution colonoscope without any staining and after indigo carmine dye according to the Kudo classification. RESULTS: The resected polyps included 48 adenomatous and 225 nonadenomatous polyps. When histologically confirmed hyperplastic polyps were compared with adenomatous polyps, the prediction of hyperplastic polyps based on endoscopic findings had a sensitivity of 93%, a specificity of 60%, and an overall accuracy of 81%. The corresponding sensitivity, specificity, and overall accuracy after indigo carmine dye were 94%, 64%, and 83%, respectively. CONCLUSIONS: The results suggest that the chromoendoscopy only marginally improves the determination between hyperplastic and adenomatous polyps when using high-resolution colonoscopes. The overall accuracy rate increased after dyeing, from 81% to 83%. The omission of histopathologic analysis cannot yet be achieved by chromoendoscopy.

Adenoma↗
PubMed2005

Colorectal polyps: detection with dark-lumen MR colonography versus conventional colonoscopy.

PURPOSE: To prospectively compare dark-lumen magnetic resonance (MR) colonography with conventional colonoscopy in the detection of colorectal polyps. MATERIALS AND METHODS: Local ethical committee approval and informed consent were obtained. One hundred consecutive patients (56 men, 44 women; mean age +/- standard deviation, 67.7 years +/- 14.7; range, 25-82 years) who were referred for conventional colonoscopy from January 2003 to January 2004 underwent MR colonography and conventional colonoscopy after standard precolonoscopic bowel cleansing. Colonoscopy was performed immediately after MR colonography. For MR colonography, the colon was filled with approximately 2000 mL of tap water. Imaging was performed with a 1.5-T MR unit with patients in the prone position. A T1-weighted three-dimensional volumetric interpolated breath-hold sequence was performed before and 75 seconds after intravenous administration of 0.2 mmol gadobenate dimeglumine per kilogram of body weight. Results of MR colonography were analyzed on a per-polyp and per-patient basis. Findings at colonoscopy were used as the reference for determining accuracy, sensitivity, specificity, and positive and negative predictive values of MR colonography. RESULTS: Of 100 patients recruited for study, 92 (52 men, 40 women; mean age, 61.5 years +/- 14.5; range, 25-82 years) underwent complete MR and conventional colonoscopy examinations. Forty-three of the 92 patients (47%) had normal findings at conventional colonoscopy. In the other 49 patients (53%), conventional colonoscopy depicted 107 polyps (82 adenomas, 25 hyperplastic polyps) and seven carcinomas. At per-polyp analysis, sensitivity of MR colonography in the detection of adenomatous polyps was 100% for polyps at least 10 mm in diameter and 84.2% for polyps 6-9 mm in diameter. At per-patient analysis, the accuracy of MR colonography was 93.1% (sensitivity, 89%; specificity, 96%) if detection of adenomatous polyps of all sizes was considered. CONCLUSION: Dark-lumen MR colonography is a promising modality with high accuracy for detecting colorectal polyps larger than 5 mm in diameter.

Adult↗
PubMed2005

[MRI in gastrointestinal diseases].

Magnetic resonance imaging (MRI) has been called the most important development in medical diagnosis since the discovery of the X-ray more than 100 years ago. The effectiveness of MRI has been expanded to a variety of gastrointestinal disorders. The gastroenterologist's attention is currently focused on biliopancreatic and bowel diseases. Magnetic resonance cholangiopancreatography (MRCP) has become a competitive replacement for diagnostic endoscopic retrograde cholangiopancreatography (ERCP) in a variety of hepatobiliary and pancreatic diseases. MR enteroscopy has the potential to become the preferred method for evaluating the entire small bowel, while on the other hand virtual colonoscopy is far from being promoted as a tool for general screening purposes in suspected colon diseases. In summary, whether or not the survival of endoscopy is under debate, MRI could mark a historic turning point in gastroenterology. So, MRI hardware might interdisciplinarily be used by, e. g., radiologists and gastroenterologists.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed2005

Endoluminal therapy of GERD with a new endoscopic suturing device.

BACKGROUND: Endoscopic, endoluminal therapy might be an alternative treatment option in light of the costs of proton pump inhibitor therapy and possible complications after laparoscopic surgery. The aim of the current study was to assess the efficacy and the safety of a new endoluminal suture device (ESD) in pig models and humans. Secondly, 3 and 6 months' follow-ups were performed, and possible complications and their management were evaluated. METHODS: In the preclinical phase of the study, suturing procedures were practiced and evaluated in 8 pig models (Erlanger Endo Trainer). In the clinical phase, 20 patients with mild esophagitis, small or no hiatal hernia, and signs of abnormal acid exposure (pH measurements) were enrolled. Therapeutic endoscopy (propofol sedation) was performed with the flexible suture and the Ti-Knot devices, which were introduced over an external accessory channel, fixed on the endoscope. One to 3 sutures were applied per patient at the gastroesophageal junction. A 3 months' follow-up included upper endoscopy, manometry, 24-hour pH study, and clinical questionnaires. RESULTS: Visibility with the new device was good, and, in all cases, sutures could be applied with only minor complications. In the animal model, the stitches reached the muscularis propria. However, the 3-month follow-up showed that only 12% of all plications persisted over this short period in humans. In addition, the clinical response was poor (no significant changes after the procedure: pH study, proton pump inhibitor intake, lower-esophageal sphincter pressure on manometry). In two patients, acute bleeding occurred, which was successfully controlled with endoscopic therapy. However, these patients were observed overnight in the hospital without further complications. The study was interrupted after 3 months because of the results of the interim analysis. CONCLUSIONS: The new endoscopic suturing device allows a feasible and safe technique for application of endoscopic sutures. The procedure could be performed on an outpatient basis by using sedation with propofol. However, the clinical outcome was very limited because of the high number of lost or failed plications. Thus, the ESD currently cannot be recommended in the treatment of patients with GERD.

Adolescent↗
PubMed2005

Palliation of nonresectable bile duct cancer: improved survival after photodynamic therapy.

OBJECTIVES: Preliminary uncontrolled studies of photodynamic therapy (PDT) of bile duct cancer (BDC) have shown astonishingly good results in the reduction of cholestasis, improvement of life quality, and potential improvement of survival time. Therefore, we investigated the influence of PDT on survival time in advanced BDC in a randomized controlled study. METHODS: Thirty-two patients with nonresectable BDC were randomized. In the PDT group 48 h after intravenous application of 2 mg/kg body weight of Photosan-3((R)), light activation was performed. In the control group, patients were treated with endoprostheses but no PDT. RESULTS: PDT group and the control group were comparable due to age, gender, performance status, bilirubin level, and BDC stage (Bismuth classification). The median survival time after randomization was 7 months for the control group and 21 months for the PDT group (p= 0.0109). In half of the initially percutaneously treated patients, we could change from percutaneous to transpapillary drainage after PDT. Four patients showed infectious complications after PDT versus one patient in the control group. DISCUSSION: PDT is minimally invasive but shows a considerable postinterventional cholangitis rate. PDT has the potential to result in a changeover of current palliative treatment of BDC.

Aged↗
PubMed2004

Capsule endoscopy, technical impact, benefits and limitations.

BACKGROUND: The small bowel is the most difficult part of the bowel to examine owing to the distance from the mouth to anus. Conventional endoscopic techniques for examining the small bowel are limited by its length and its multiple, complex, looped configurations. However, for a wide variety of specific lesions, the diagnostic value of other tests for imaging the small bowel is low. For the first time wireless capsule endoscopy has made non-invasive imaging of the entire small bowel possible. A number of peer-reviewed studies has been published that compare the method with push-enteroscopy in patients with obscure gastrointestinal bleeding and have shown superior diagnostic results. CONCLUSION: Capsule endoscopy has opened up new horizons for the diagnosis of small-bowel disease. All published studies show a higher diagnostic yield of capsule endoscopy compared with push-enteroscopy and standard radiographic investigations.

Abdominal Pain↗
PubMed2004

Illness experience before and after an initiative to identify, treat, and prevent Helicobacter pylori-related diseases in the workplace.

Objective outcome measures are needed to confirm the merits of large-scale health initiatives in the workplace. We used aggregate medical claims data to evaluate the illness experience of 5160 employees during the 2 years after versus the 2 years before an intervention intended to identify, treat, and prevent Helicobacter pylori-related illnesses. Across all participants, a 2.1-fold reduction (95% confidence interval 1.4-3.1) in ulcer-related illness episodes and a marginal 1.1-fold reduction (95% confidence interval 0.9-1.4) in episodes due to other stomach and duodenal diseases were achieved. Improvement in claims experience was most notable among 250 employees with ulcer findings on the screening examination. This H. pylori health initiative appears to have contributed to a cost-effective reduction in subsequent illness episodes due to ulcer and possibly due to other stomach and duodenal disease.

Adult↗
PubMed2004

ERCP and MRCP in the differentiation of pancreatic tumors.

The introduction of endoscopic retrograde cholangiopancreatography (ERCP) in the early 1970s provided gastroenterologists with a number of diagnostic as well as therapeutic possibilities for examining biliopancreatic systems. In the meantime, magnetic resonance cholangiopancreatography presents a non-invasive alternative to diagnostic ECRP providing the advantage of a lower rate of possible complications. This article addresses the two methods presently available for differentiating pancreatic tumors. The objective of this article is to describe the advantages and disadvantages as well as the possibilities inherent in both methods.

Adenoma, Islet Cell↗
PubMed2003

[Optimized diabetes therapy in type 2 diabetics].

BACKGROUND: With the prevalence of type 2 diabetes mellitus having increased to approximately 8% during recent years and a further rise likely, type 2 diabetes will develop into a major health care problem in Europe. There are roughly 8 million diabetics in Germany, with another 4 million estimated unknown case. CLINICAL FEATURES: Diabetes is an accepted risk factor in the development of micro- and macrovascular complications. These complications generate enormous costs in our health care system. The optimal treatment of diabetic complications will minimize the cost to the health care system in the long run. Therefore, it is necessary to relay current therapeutic guidelines to medical personnel on a widespread basis. AIMS AND CONCLUSION: This publication summarizes current therapeutic options in glycemic control of type 2 diabetics which correspond to 95% of all diabetics. Recently, a national guideline has been developed by the "Arzneimittelkommission der deutschen Arzteschaft", the "Deutsche Diabetes- Gesellschaft", the "Fachkommission Diabetes Sachsen", the "Deutsche Gesellschaft für Innere Medizin e. V.", and the "Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften". In this guideline, treatment recommendations are made according to the criteria of evidence-based medicine. It is the basis of this review. In addition, the significance of the modern option of functional insulin therapy (FIT) in the treatment of type 2 diabetes will be explained. In closing, innovative alternatives of applying insulin will be discussed. Unquestionably, all other risk factors such as hypertension and/or hyperlipidemia also have to be treated optimally. These risk factors will not be discussed in this publication.

Adolescent↗
PubMed2003

Prospective, randomized, single-center trial comparing 3 different 10F plastic stents in malignant mid and distal bile duct strictures.

BACKGROUND: The aim of this study was to determine whether patency rates differ with respect to the material, design, and surface texture of 3 different plastic stents. METHODS: A total of 120 patients (median age 70.5 years; interquartile range 62-78 years) with malignant mid or distal bile duct strictures, seen between March 1996 and May 1999, were prospectively randomized to receive a 10F polyurethane stent, a Teflon Tannenbaum stent, or a hydrophilic hydromer-coated polyurethane stent. The primary study outcome measure was the interval between stent insertion and the first episode of clogging (or the presence of jaundice at death without stent exchange). All 3 types of stent were studied by scanning electron microscopy before insertion. RESULTS: A total of 19 patients were excluded from long-term follow-up. Median duration of stent patency was 76 days overall (interquartile range 29-150 days) and 76 (interquartile range 30-110) days for hydrophilic hydromer-coated polyurethane, 108 (interquartile range 33-186) days for 10F polyurethane, and 58 (interquartile range 21-188) days for Teflon Tannenbaum stents. There were no statistically significant differences among stent types. The hydrophilic hydromer-coated stent had the smoothest surface, as visualized by scanning electron microscopy. CONCLUSIONS: No significant differences in the patency of 3 types of stents were detected in this randomized trial. In particular, the hydrophilic hydromer-coated plastic stent did not provide clinical advantages despite its smooth surface.

Aged↗
PubMed2003

Endoscopic stenting for postoperative biliary strictures due to hepatic hydatid disease: effectiveness and long-term outcome.

BACKGROUND: Postoperative strictures due to hepatic hydatid disease caused by Echinococcus surgery is considered to be a rare cause of benign bile duct strictures, especially in the Western world. GOALS: The aim of this retrospective study is to demonstrate possible characteristics of the strictures as well as the effectiveness of long-term endoscopic stenting. STUDY: Between 1994 and 2001, we treated 10 of these cases in our clinic. All patients had surgery for hepatic Echinococcus disease one or more times. These types of benign biliary strictures, secondary to surgery of hepatic hydatid disease, were multiple and located in the proximal common bile duct. Endoscopic stent therapy was carried out in all cases containing transpapillary approach with plastic prostheses (7.5-11 French) or transhepatic approach with Yamakawa prostheses (16 French). Nine patients were available for follow-up. RESULTS: In 6 patients (66%), the stents were removed after a median period of 22.5 months with radiologic and clinical signs of improvement. Three patients required prolonged dilatation therapy because of stricture-recurrence. There was low overall morbidity and we recognized no therapy-associated mortality. CONCLUSIONS: Endoscopic stent therapy is a safe nonoperative method for the treatment of postoperative benign biliary strictures due to hepatic hydatid disease.

Aged↗