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Uwe Weickert

Publications and source records attributed to Uwe Weickert.

11 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

Diagnosis of obscure gastrointestinal bleeding by intra-operative enteroscopy in 81 consecutive patients.

AIM: To analyze the results and complications of intra-operative enteroscopy (IOE) by investigating a series of selected patients with bleeding suspected to originate from the small intestine. METHODS: Eighty-one patients (mean age: 65 years) including 40 males (49.4%) and 41 females (50.6%) with obscure gastrointestinal bleeding underwent IOE between 1990 and 2004. The patients were identified from a database and data were selected from the patients' charts retrospectively. All the patients had undergone at least one non-diagnostic esophagogastroduodenoscopy, colonoscopy, standard enteroscopy and a negative abdominal ultrasound scan before IOE. RESULTS: The median minimal hemoglobin level in the patients was 59 + 15 g/L and 72.8% of the patients required transfusion of packed erythrocytes previously. A bleeding source was detected in 68 (84%) of the patients during IOE. Angiodysplasiae were found in 44 patients (54.3%) and 9 patients (11.1%) were affected by ulcers in the small intestine. A tumor in the small intestine was detected in another 6 patients. The treatment consisted of argon-plasma-coagulation, surgical suture or limited resection in most of the patients. CONCLUSION: Intra-operative enteroscopy is still used for the diagnosis of suspected small bowel bleeding. Recent developments such as wireless capsule endoscopy and double balloon enteroscopy, may lead to the replacement of IOE in the future.

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↗
PubMed2006

Bacteremia after diagnostic conventional laparoscopy and minilaparoscopy: a prospective study in 100 patients.

BACKGROUND/GOALS: Diagnostic laparoscopy under sedoanalgesia is a valuable tool in the work-up of liver diseases and is helpful as a staging procedure. The rate of bacteremia caused by this procedure is unknown, in particular when performed as minilaparoscopy. STUDY: A 100 consecutive patients having undergone diagnostic laparoscopy carried out either conventionally (group I, n=50) or as minilaparoscopy (group II, n=50) were prospectively enrolled in this study. Blood cultures were drawn before and within 5 minutes after the procedure. Risk factors for bacteremia were evaluated. RESULTS: Bacterial growth occurred in 4 blood cultures drawn immediately after laparoscopy. No patient developed fever or other signs of infection in the follow-up. Risk factors predisposing to bacteremia could not be identified. CONCLUSIONS: Conventional diagnostic laparoscopy under sedoanalgesia and minilaparoscopy are associated with a low rate of bacteremia as in diagnostic upper endoscopy.

Adult↗
PubMed2006

Risk factors for symptomatic stone recurrence after transpapillary laser lithotripsy for difficult bile duct stones using a laser with a stone recognition system.

BACKGROUND: Laser-induced shock-wave lithotripsy (LISL) is successfully used for the treatment of difficult bile duct stones. The aim of this study was to assess the long-term risk for a symptomatic bile duct stone recurrence after LISL and to detect risk factors predicting recurrence. METHODS: Between 1993 and 2001, 80 patients with difficult bile duct stones were successfully treated by intracorporeal LISL through the papilla of Vater. Seventy-one of these patients [median age, 65.8 years; 51 women (71.8%)] were followed for a median (range) period of 58 (1-114) months. RESULTS: Eleven patients (15.5%) had a symptomatic stone recurrence. The median (range) period between laser lithotripsy and recurrence was 40 (5-85) months. The presence of a bile duct stenosis (P=0.032) and a body-mass index below 25 (P=0.025) were significantly associated with an increased risk for stone recurrence. A gallbladder in situ, the presence of gallbladder stones, dilation of the bile duct, or a peripapillary diverticulum was not associated with stone recurrence. CONCLUSIONS: The presence of a bile duct stenosis is significantly related to bile duct stone recurrence after treatment with LISL. The impact of the body mass index on stone recurrence is interesting. The gallbladder status did not predict stone recurrence in our study.

Aged↗
PubMed2005

Improved preoperative tumor staging by 5-aminolevulinic acid induced fluorescence laparoscopy.

BACKGROUND: We report our data in 35 patients who underwent preoperative conventional and fluorescence-based staging laparoscopy. We use the data to address the questions of whether fluorescence examination increases the yield of metastatic lesions and alters treatment intervention. METHODS: Fluorescence laparoscopy was successfully performed in 30 patients with GI malignancies. After sensitization with 5-aminolevulinic acid, conventional white-light mode and fluorescence-light laparoscopies were sequentially performed. A suspected malignancy was biopsied. OBSERVATIONS: In 5 patients, examinations were incomplete because of adhesions. In 9 of 10 patients, hepatic or peritoneal metastases were detected by white-light examination. In 4 of these 9, blue-light examination yielded more metastatic lesions. In one patient with no lesions by white- or blue-light examination, surgery revealed hepatic metastasis in a location not accessible to laparoscopic examination. In 18 patients, surgery confirmed the absence of metastatic lesions. CONCLUSIONS: A fluorescence, blue-light examination yielded more lesions than the conventional white-light examination but did not alter treatment intervention and did not enhance yield when metastatic lesion is in an inaccessible location. Continued research should focus on whether treatment intervention will be altered by the fluorescence examination.

Administration, Oral↗
PubMed2005

A prospective two-center study comparing wireless capsule endoscopy with intraoperative enteroscopy in patients with obscure GI bleeding.

BACKGROUND: Capsule endoscopy enables noninvasive diagnostic examination of the entire small intestine. However, sensitivity and specificity of capsule endoscopy have not been adequately defined. We, therefore, compared capsule endoscopy by using intraoperative enteroscopy as a criterion standard in patients with obscure GI bleeding. METHODS: Forty-seven consecutive patients with obscure GI bleeding (11 with ongoing overt bleeding, 24 with previous overt bleeding, and 12 with obscure-occult bleeding) from two German gastroenterologic centers were included. All patients who had a prior nondiagnostic evaluation, including upper endoscopy, colonoscopy with a retrograde examination of the distal ileum, and push enteroscopy, underwent capsule endoscopy followed by intraoperative enteroscopy. RESULTS: Capsule endoscopy identified lesions in 100% of the patients with ongoing overt bleeding, 67% of the patients with previous overt bleeding, and 67% of the patients with obscure-occult bleeding. Angiectasias were the most common source of bleeding (n = 22). Capsule endoscopy showed the source of bleeding in 74.4% of all patients. The method was more effective in patients with ongoing bleeding. Compared with intraoperative enteroscopy sensitivity, specificity, and positive and negative predictive values of capsule endoscopy were 95%, 75%, 95%, and 86%, respectively. CONCLUSIONS: Capsule endoscopy has high sensitivity and specificity to detect a bleeding source in patients with obscure GI bleeding. Thus, wireless capsule endoscopy can be recommended as part of the routine work-up in patients with obscure GI bleeding.

Adolescent↗
PubMed2005

Diagnosis of liver cirrhosis: a comparison of modified ultrasound and laparoscopy in 100 consecutive patients.

BACKGROUND/GOALS: Liver cirrhosis, the final stage of chronic liver disease, is characterized by an unfavorable prognosis and an increased risk of hepatocellular carcinoma and also requires an appropriate management. Laparoscopy, the gold standard in the diagnosis of cirrhosis, is hampered by its invasiveness. Therefore, a noninvasive method for diagnosing liver cirrhosis would be of great benefit. STUDY: A consecutive series of 100 patients, sent to our gastroenterological unit for diagnostic laparoscopy, underwent a standardized ultrasonographic examination prior to laparoscopy. RESULTS: Conventional ultrasonographic examination revealed a sensitivity of 55% and a specificity of 86% in the diagnosis of cirrhosis. Considering the assessment of the transmission of heart pulsation on the liver surface, the corresponding values improved by increasing to 85% and 93%. CONCLUSION: Evaluating the transmission of heart pulsation on the liver surface improves the ability of ultrasound to diagnose liver cirrhosis; therefore, it should be an integral part of routine sonographic examination of the liver.

Adult↗
PubMed2004

High frequency of colorectal adenoma in patients with duodenal adenoma but without familial adenomatous polyposis.

BACKGROUND: Duodenal adenomas are extremely common in patients with familial adenomatous polyposis. However, it is uncertain whether patients with duodenal adenomas without familial adenomatous polyposis are at greater risk for colorectal neoplasia and, therefore, should routinely undergo surveillance colonoscopy. The aim of this study was to determine whether there is a correlation between non-papillary duodenal adenoma without familial adenomatous polyposis and colorectal adenoma. METHODS: Twenty-five patients with non-papillary duodenal adenomas without familial adenomatous polyposis, seen from January 1990 to April 2003, were retrospectively evaluated. RESULTS: Non-papillary duodenal polyps were diagnosed by endoscopy in the 25 patients. Of these, 21 underwent colonoscopy and one underwent proctoscopy. The mean age of these 22 patients (12 women, 10 men) was 69 years (range 50-83 years). Sixteen of the 22 patients (72.7%) with duodenal adenomas had associated colorectal adenomas. A total of 38 adenomas and one colorectal cancer were detected. The mean size of the polyps was 6.2 mm (range 3-15 mm). The adenomas were removed by snare excision or with a biopsy forceps. CONCLUSIONS: Based on the results of this uncontrolled, retrospective study, the frequency of colorectal adenomas in patients with duodenal polyps without familial adenomatous polyposis appears to be increased compared with the general population. All patients with duodenal polyps should undergo surveillance colonoscopy for colorectal adenomas. A prospective study to definitively establish the frequency of colorectal adenomas in these patients is warranted.

Adenoma, Villous↗
PubMedDate not supplied

Self-expanding metal stents versus plastic prostheses in the palliation of malignant dysphagia: long-term outcome of 153 consecutive patients.

BACKGROUND: Malignant dysphagia due to esophagogastric cancer is associated with poor overall prognosis. Placements of self-expandable metal stents or plastic tubes are established methods as palliative treatment options. As an alternative and/or complementary therapy, radiologic techniques (external beam radiation/brachytherapy) and locally endoscopic techniques (laser, APC-beamer, PDT) are often used. STUDY AND GOALS: Retrospective trial of 153 patients treated in our department between 1993 and 2001. Forty-five patients received a plastic tube (Group A) and 108 patients were treated with metal stents (Group B). Both groups were compared for improvement of dysphagia score, survival, recurrent dysphagia and complications. RESULTS: Stent placement was successful in 41 of 45 (93%) patients of Group A and 107 of 108 (99%) of Group B. The median dysphagia score improved significantly in Group A (from 3.03 to 1.55, P = 0.010) and Group B (from 2.77 to 1.44, P = 0.009). Recurrent dysphagia was noted in 12 of 45 (27%) patients of Group A and 27 of 108 (25%) patients of Group B. Median survival time after stent insertion was 78 days (Group A) and 113 days (Group B). Overall complications occurred in 15 of 45 (33%) patients of Group A and 28 of 108 (26%) patients of Group B. However, significantly (P = 0.05) more major complications were seen in Group A than in Group B (22% vs. 9%). CONCLUSIONS: Our results indicate a marginal clinical benefit for metal stents versus plastic tubes in malignant dysphagia in the long run. However, metal stents seem to be safer and associated with a prolonged improvement of dysphagia score.

Adenocarcinoma↗