Endoskopische Antirefluxmethoden sind als alternative Behandlungmethode bei Patienten mit gastro-ösophagealer Refluxerkrankung eingeführt worden. Die endoskopische Antirefluxtherapie mit einer submukosalen Implantation von Hydrogelrothesen in die distale Speiseröhre (Gatekeeper-Methode) stellt ein neues.

BACKGROUND AND AIMS:Endoscopic assessment of the length and area of Barrett's esophagus (BE) has become crucial in assessing its spontaneous course as well as any effect of pharmacological or endoscopic treatment. Little, however, is known about the extent to which the endoscopic assessment of BE length and area correlates with the histopathological confirmation of BE epithelium.PATIENTS AND METHODS:75 consecutive patients (mean age 60 years; 58 men, 17 women) were included in a prospective study on the basis of the endoscopic suspicion of BE. BE was endoscopically defined as gastric-type epithelium between the proximal cardiac folds and the Z line, on moderate air insufflation. Stepwise four-quadrant biopsies (4QB) were then taken, beginning at the proximal cardiac folds and then every 2 cm up to the Z line.RESULTS:Among the 75 study patients, BE was histologically verified in 57 cases (group 1) and not confirmed in any of the endoscopic biopsy samples in 18 cases (group 2). In group 1, the mean difference between the endoscopic and histological assessment of BE length was + 1 cm (range 0 - 5 cm); when determining the BE area histologically from 4QB the mean difference to the endoscopic determination was + 36 % (range 0 - 93 %). These differences were independent of the presence and degree of hiatal hernia or the presence of long or short BE.CONCLUSIONS:In the majority of patients, there is only a moderate correlation between the endoscopic and the histological extent of BE. However, we also found a substantial individual variability in endoscopic-histological correlation; therefore studies on the effects of treatment on BE must consider both the endoscopic and histopathological BE lengths.

BACKGROUND AND AIMS:Endoscopic surveillance including stepwise four quadrant biopsies (4QB) is still regarded as the standard approach in patients with Barrett's oesophagus (BO). Several methods such as dye staining with methylene blue (MB) and tissue autofluorescence (AF) have been advocated to reduce the number of biopsies. We assessed their sensitivity and specificity compared with the standard approach-that is, endoscopy with 4QB-in the surveillance of a mixed BO population.PATIENTS AND METHODS:Thirty five consecutive BO patients (mean age 64.9 years; 30 men, five women) were included in the study. AF endoscopy was followed by high resolution video endoscopy (VE) plus tissue staining with 0.5% MB. Biopsies were taken from any suspicious area found on any of the above tests, in addition to 4QB every 2 cm. The results were classified as either positive or negative for the various tests used. Histopathological results were used as the reference standard.RESULTS:In the 35 study patients, a total of 345 biopsies showed low grade dysplasia (LGD) in 88 biopsies, high grade dysplasia (HGD) in 19 biopsies, and carcinoma in 12 biopsies. The sensitivity and specificity rates for AF and MB for the diagnosis of cancer or dysplasia versus BO mucosa without dysplasia were 21%/91% and 37%/91%, respectively. 4QB revealed five cancer/HGD areas and 76 LGD areas not detected by AF, MB, or VE. The additional yield of MB and AF over VE with 4QB concerned only one HGD area (in the vicinity of a cancer) and seven LGD areas.CONCLUSIONS:Due to their low sensitivity, AF and MB are not suitable techniques for reducing the high numbers of routine biopsies needed for finding additional foci of HGD or cancer. Careful endoscopic observation and stepwise four quadrant biopsy therefore still represent the gold standard for surveillance of Barrett's oesophagus.

BACKGROUND:In most European countries, training in GI endoscopy has largely been based on hands-on acquisition of experience in patients rather than on a structured training programme. With the development of training models systematic hands-on training in a variety of diagnostic and therapeutic endoscopy techniques was achieved. Little, however, is known about methods of objectively assessing trainees' performance. We therefore developed an assessment 'score card' for upper GI endoscopy and tested it in endoscopists with various levels of experience. The aim of the study was therefore to assess interobserver variations in the evaluation of trainees.METHODS:On the basis of textbook and expert opinions a consensus group of eight experienced endoscopists developed a score card for diagnostic upper GI endoscopy with biopsy. The score card includes an assessment of the single steps of the procedure as well as of the times needed to complete each step. This score card was then evaluated in a further conference including ten experts who blindly assessed videotapes of 15 endoscopists performing upper GI endoscopy in a training bio-simulation model (the 'Erlangen Endo-Trainer'). On the basis of their previous experience (i. e. the number of endoscopies performed) these 15 endoscopists were classified into four groups: very experienced, experienced, having some experience and inexperienced. Interobserver variability (IOV) was tested for the various score card parameters (Kendall's rank-correlation coefficient 0.0-0.5 poor, 0.5-1.0 good agreement). In addition, the correlation between the score card assessment and the examiners' experience levels was analysed.RESULTS:Despite poor IOV results for all the parameters tested (Kendall coefficient < 0.3), the assessment parameters correlated well when the examiners' different experience levels were taken into account (correlation coefficient 0.59-0.89, p < 0.05). The score card parameters were suitable for differentiating between the four groups of examiners with different levels of endoscopic experience.CONCLUSIONS:As expected with scores involving subjective assessment of performance, the variability between reviewers was substantial. Nevertheless, the assessment score was capable of distinguishing reliably between different experience levels in terms of a good individual observer consistency. The score card can therefore be used to document both training status and progress during endoscopy training courses using bio-simulation models, and this might be able to provide improved quality assurance in GI endoscopy training.

Background:Virtual colonoscopy has been advocated as a diagnostic method to replace diagnostic colponoscopy.Most previous studies used the CT technique.We wanted to evaluate the diagnostic reliability of virtual MR-colonoscopy (VC) in comparison to conventional colonoscopy.Patients and Methods: 117 patients (57 male, 60 female, median age 69 years, range

The 185 metre high Katse Dam in Lesotho completed in 1997 is the highest dam in Southern Africa. A geodetic monitoring system forms part of the dam safety surveillance system designed for the dam. The primary geodetic network beacons were constructed in 1991 before construction of the dam commenced in order to establish their long-term stability. Reduced geodetic measurements of the arch started in 1995 during construction of the dam but full-scale measurements could only commence in February 1998 after completion. The practical aspects of the geodetic measuring system, combined with pendulums are described in detail. The incorporation of this technique in the dam safety surveillance system is illustrated.

The multimedia teleconsultation service ENDOTEL launches in May 2000 with its asynchronous component. In the initial phase, three hospitals and four general practitioners use the service to consult a specialist in the domain of gastroenterology and endoscopy. By validation of the patient information, i.e. videos, voice clips, still images and text, the experts can decide the further proceeding, for example, whether a patient shall be transported to a specialized hospital or not (cost-saving). We report about the experiences during the initiation and the first months of operation.

AbstractThe solubility equilibrium of ε−Zn(OH)2 in 02M (K)NO3 has been investigated at 25°C with 65Zn as tracer. All data could be explained assuming the reaction with log *Ks0 = 11,72 ± 0,02 [25°C 0,2 M(K)NO3].

AbstractThe isotopic ion exchange between various forms of 59Fe labelled synthetic Fe3O4 and FeC12‐solution was investigated from 9 to 95°C, by measuring the activity of the solution after various reaction times. The observed exchange rate was compared with the theoretically calculated rate for a diffusion controlled reaction. The mathematics of the heterogeneous isotopic ion exchange is discussed. For short times a deviation from the y|√t relationship was observed and attributed to an initial process, superimposed on the diffusion reaction. This initial process probably consists of a rapid exchange of the solution with the first atomic layers of the solid. This problem will be treated mathematically in a subsequent paper. Diffusion coefficients (D8) can be estimated from the slope of the straight line in the y|√t plot. From the temperature dependence of the D8‐values the activation energy was calculated to be about 7 kcal/mole and the self diffusion coefficient (D0) of Fe in Fe3O4 was estimated to be 5 ± 3 · 10−6cm2s−1.

The oxidation of Fe3O4 has been investigated using the methods of differential thermoanalysis and thermogravimetry. Preparation with an average particle size ranging from ∼ 100–7500 A were used.