U. Seitz
University of Hamburg
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Featured researches published by U. Seitz.
Gastroenterology | 2008
Wouter L. Curvers; Lubbertus Baak; Ralf Kiesslich; Arnoud H. Van Oijen; Thomas Rabenstein; Krish Ragunath; Jean–Francois Rey; Pieter Scholten; U. Seitz; Fiebo J. ten Kate; Paul Fockens; Jacques J. Bergman
BACKGROUND & AIMSnThe aim of this study was to compare magnified still images obtained with high-resolution white light endoscopy, indigo carmine chromoendoscopy, acetic acid chromoendoscopy, and narrow-band imaging to determine the best technique for use in Barretts esophagus.nnnMETHODSnWe obtained magnified images from 22 areas with the 4 aforementioned techniques. Seven endoscopists with no specific expertise in Barretts esophagus or advanced imaging techniques and 5 international experts in this field evaluated these 22 areas for overall image quality, mucosal image quality, and vascular image quality. In addition, the regularity of mucosal and vascular patterns and the presence of abnormal blood vessels were evaluated, and this was correlated with histology.nnnRESULTSnThe interobserver agreement for the 3 features of mucosal morphology with white light images ranged from kappa = 0.51 (95% confidence interval [CI]: 0.46-0.55) to kappa = 0.53 (95% CI: 0.50-0.57) for all observers, from kappa = 0.43 (95% CI: 0.33-0.54) to kappa = 0.53 (95% CI: 0.41-0.64) for experts, and from kappa = 0.51 (95% CI: 0.15-0.33) to kappa = 0.64 (95% CI: 0.58-0.70) for nonexperts. The interobserver agreement in these groups did not improve by adding one of the enhancement techniques. The yield for identifying early neoplasia with white light images was 86% for all observers, 90% for experts, and 84% for nonexperts. The addition of enhancement techniques did not improve the yield neoplasia.nnnCONCLUSIONSnThe addition of indigo carmine chromoendoscopy, acetic acid chromoendoscopy, or narrow-band imaging to white light images did not improve interobserver agreement or yield identifying early neoplasia in Barretts esophagus.
Gastrointestinal Endoscopy | 2008
Stefan Seewald; Tiing Leong Ang; Hiroo Imazu; Mazen Naga; Salem Omar; Stefan Groth; U. Seitz; Yan Zhong; Frank Thonke; Nib Soehendra
BACKGROUNDnN-butyl-2-cyanoacrylate has been successfully used for the treatment of bleeding from gastric fundal varices (FV). However, significant rebleeding rates and serious complications including embolism have been reported.nnnOBJECTIVEnOur purpose was to analyze the safety and efficacy of N-butyl-2-cyanoacrylate for FV bleeding by using a standardized injection technique and regimen.nnnDESIGNnRetrospective.nnnSETTINGnTwo tertiary referral centers.nnnPATIENTSnA total of 131 patients (91 men/40 women) with FV underwent obliteration with N-butyl-2-cyanoacrylate by a standardized technique and regimen.nnnINTERVENTIONSn(1) Dilution of 0.5 mL of N-butyl-2-cyanoacrylate with 0.8 mL of Lipiodol, (2) limiting the volume of mixture to 1.0 mL per injection to minimize the risk of embolism, (3) repeating intravariceal injections of 1.0 mL each until hemostasis was achieved, (4) obliteration of all tributaries of the FV, (5) repeat endoscopy 4 days after the initial treatment to confirm complete obliteration of all visible varices and repeat N-butyl-2-cyanoacrylate injection if necessary to accomplish complete obliteration.nnnMAIN OUTCOME MEASUREMENTSnImmediate hemostasis rate, early rebleeding rate, bleeding-related mortality rate, procedure-related complications, long-term cumulative rebleeding-free rate, and cumulative survival rate.nnnRESULTSnInitial hemostasis and variceal obliteration were achieved in all patients. The mean number of sessions was 1 (range 1-3). The mean total volume of glue mixture used was 4.0 mL (range 1-13 mL). There was no occurrence of early FV rebleeding, procedure-related complications, or bleeding-related death. The cumulative rebleeding-free rate at 1, 3, and 5 years was 94.5%, 89.3%, and 82.9%, respectively.nnnCONCLUSIONnObliteration of bleeding FV with N-butyl-2-cyanoacrylate is safe and effective with use of a standardized injection technique and regimen.
Human Pathology | 2009
Andreas Marx; Timo Wandrey; Philipp Simon; Agatha Wewer; Tobias Grob; Uta Reichelt; Sarah Minner; Ronald Simon; Martina E. Spehlmann; Wolfgang Tigges; Nib Soehendra; U. Seitz; Stefan Seewald; Jakob R. Izbicki; Emre F. Yekebas; Jussuf T. Kaifi; Martina Mirlacher; Luigi Terracciano; A. Fleischmann; Andreas Raedler; Guido Sauter
Identification of dysplasia in inflammatory bowel disease represents a major challenge for both clinicians and pathologists. Clear diagnosis of dysplasia in inflammatory bowel disease is sometimes not possible with biopsies remaining indefinite for dysplasia. Recent studies have identified molecular alterations in colitis-associated cancers, including increased protein levels of alpha-methylacyl coenzyme A racemase, p53, p16 and bcl-2. In order to analyze the potential diagnostic use of these parameters in biopsies from inflammatory bowel disease, a tissue microarray was manufactured from colons of 54 patients with inflammatory bowel disease composed of 622 samples with normal mucosa, 78 samples with inflammatory activity, 6 samples with low-grade dysplasia, 12 samples with high-grade dysplasia, and 66 samples with carcinoma. In addition, 69 colonoscopic biopsies from 36 patients with inflammatory bowel disease (28 low-grade dysplasia, 8 high-grade dysplasia, and 33 indefinite for dysplasia) were included in this study. Immunohistochemistry for alpha-methylacyl coenzyme A racemase, p53, p16 and bcl-2 was performed on both tissue microarray and biopsies. p53 and alpha-methylacyl coenzyme A racemase showed the most discriminating results, being positive in most cancers (77.3% and 80.3%) and dysplasias (94.4% and 94.4%) but only rarely in nonneoplastic epithelium (1.6% and 9.4%; P < .001). Through combining the best discriminators, p53 and alpha-methylacyl coenzyme A racemase, a stronger distinction between neoplastic tissues was possible. Of all neoplastic lesions, 75.8% showed a coexpression of alpha-methylacyl coenzyme A racemase and p53, whereas this was found in only 4 of 700 nonneoplastic samples (0.6%). alpha-methylacyl coenzyme A racemase/p53 coexpression was also found in 10 of 33 indefinite for dysplasia biopsies (30.3 %), suggesting a possible neoplastic transformation in these cases. Progression to dysplasia or carcinoma was observed in 3 of 10 p53/alpha-methylacyl coenzyme A racemase-positive, indefinite-for-dysplasia cases, including 1 of 7 cases without and 2 of 3 cases with p53 mutation. It is concluded that combined alpha-methylacyl coenzyme A racemase/p53 analysis may represent a helpful tool to confirm dysplasia in inflammatory bowel disease.
Gastrointestinal Endoscopy | 2006
Stefan Seewald; Frank Thonke; Tiing-Leong Ang; Salem Omar; U. Seitz; Stefan Groth; Yan Zhong; Emre F. Yekebas; Jakob R. Izbicki; Nib Soehendra
The American Journal of Gastroenterology | 1995
K.F. Binmoeller; U. Seitz; Hans Seifert; Frank Thonke; Sanjay Sikka; Nib Soehendra
Gastroenterology | 1998
M Porthun; Boris Brand; Frank Thonke; Sabine Bohnacker; U. Seitz; Kenneth F. Binmoeller; T v Schrenck; U Matsui; Nib Soehendra
Gastrointestinal Endoscopy | 1996
Sabine Bohnacker; K.F. Binmoeller; Hans Seifert; K. Kehlbeck; U. Seitz; Frank Thonke; Nib Soehendra
Gastrointestinal Endoscopy | 1997
K.F. Binmoeller; Roland Thul; Vipulroy Rathod; Boris Brand; U. Seitz; Sabine Bohnacker; Nib Soehendra
Colonoscopy: Principles and Practice | 2007
U. Seitz; Sabine Bohnacker; Stefan Seewald; Frank Thonke; Nib Soehendra; Jerome D. Waye
Archive | 2008
Wouter L. Curvers; Lubbertus C. Baak; Ralf Kiesslich; Arnoud H. Van Oijen; Thomas Rabenstein; Krish Ragunath; Pieter Scholten; U. Seitz; Fiebo J. ten Kate; Paul Fockens; Jacques Bergman