Search results for "observer"
showing 10 items of 345 documents
Endoscopic assessment and grading of Barrett's esophagus using magnification endoscopy and narrow-band imaging: accuracy and interobserver agreement …
2010
Background: Three different classification systems for the evaluation of Barrett's esophagus (BE) using magnification endoscopy (ME) and narrow-band imaging (NBI) have been proposed. Until now, no comparative and external evaluation of these systems in a clinical-like situation has been performed. Objective: To compare and validate these 3 classification systems. Design: Prospective validation study. Setting: Tertiary-care referral center. Nine endoscopists with different levels of expertise from Europe and Japan participated as assessors. Patients: Thirty-two patients with long-segment BE. Interventions: From a group of 209 standardized prospective recordings collected on BE by using …
Interobserver variation in assessment of gastric premalignant lesions: higher agreement for intestinal metaplasia than for atrophy.
2013
Background Either atrophy or intestinal metaplasia of the gastric mucosa are considered premalignant lesions. The new operative link for gastritis assessment staging system is based on the detection of atrophy, and the operative link for assessment of intestinal metaplasia staging system is based on the detection of intestinal metaplasia. Good interobserver agreement is necessary for identification of any premalignant condition. Aims The aim of this study was to compare the agreement between findings of gastric atrophy and intestinal metaplasia by expert and general pathologists and to analyze the possible reasons behind any possible disagreement. Methods Patients with dyspeptic symptoms, a…
Dobutamine stress Doppler echocardiography: reproducibility and physiologic left ventricular filling patterns
1997
Qualitatively, dobutamine stress echocardiography has become an established procedure. Quantitative results are in great demand but this is still difficult due to limited endo- and epicardial border definition. Transmitral Doppler variables are strictly quantitative and less subjective. Furthermore, ischemic alterations precede systolic ones (ischemic cascade). There are preliminary reports of the utility of dobutamine stress Doppler echocardiography, but proof of reproducibility and left ventricular filling patterns are still lacking. Fourteen healthy volunteers (10 men, 4 women, median age 25.9 years, range 21-32 years) were investigated according to the usual dobutamine stress echocardio…
Analysis of myocardial perfusion or myocardial function for detection of regional myocardial abnormalities. An echocardiographic multicenter comparis…
2007
Background: Echocardiography based myocardial perfusion imaging and regional wall motion analysis are used for evaluation of coronary artery disease and regional myocardial abnormalities. Aim: This study sought to compare myocardial contrast echocardiography (MCE) and 2D echocardiography with regard to interobserver variability and detection of regional myocardial abnormalities. Methods: In 70 patients evenly distributed between three ejection fraction groups based on biplane cineventriculography (>55%, 35-55%, <35%), unenhanced and contrast enhanced 2D echocardiography and myocardial contrast echocardiography (MCE; SonoVue (R); Bracco) were performed. Regional watt motion and myocardial pe…
Prospective evaluation of the macroscopic types and location of early Barrett’s neoplasia in 380 lesions
2007
The macroscopic appearance of early gastric cancers, classified according to the Japanese criteria, has been shown to be an important prognostic factor for local endoscopic therapy. No prospective data about the distribution of macroscopic types and their location in early Barrett's neoplasia are available, however. The present study was conducted to evaluate the clinical applicability of this macroscopic classification and to analyze the relative proportions of the different gross types in early Barrett's neoplasms and the correlation between the macroscopic classification and the stage or grade of differentiation.A total of 344 patients with 380 Barrett's neoplastic lesions who were refer…
Chromoendoscopy and narrow-band imaging compared with high-resolution magnification endoscopy in Barrett's esophagus.
2008
Background & Aims: The 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 Barrett's esophagus. Methods: We obtained magnified images from 22 areas with the 4 aforementioned techniques. Seven endoscopists with no specific expertise in Barretes 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 abn…
On the number of measurement sites required to assess regional cerebral blood flow by laser-Doppler scanning during cerebral ischemia and reperfusion.
2001
The aim of this study was to determine whether the number of measurement sites affected the precision of regional cerebral blood flow (CBF) assessment by Laser-Doppler (LD). A simulation study was applied based on data obtained by scanning the cortex in 25 rats during baseline conditions, 15 min global cerebral ischemia and reperfusion. Random samples were repeatedly collected from 1 to 100 locations and deviations from the median of the entire CBF data pool (800 locations) were determined. Single location CBF measurements missed the true median by 24.8+/-2.2 LD-units (baseline conditions, n=100 simulations, mean+/-SEM), 2.7+/-0.6 LD-units (ischemia), and 31.9+/-2.4 LD-units (30th min reper…
Effect of observer experience in the differentiation between benign and malignant liver tumors after ultrasound contrast agent injection.
2009
OBJECTIVE: The purpose of this study was to assess the impact of the observer level of experience on the diagnostic performance of contrast-enhanced ultrasound imaging (CEUS) for differentiation between benign and malignant liver tumors. METHODS: From a computerized search, we retrospectively identified 286 biopsy-proven liver tumors (105 hepatocellular carcinomas, 48 metastases, 7 intra-hepatic cholangiocarcinomas, 33 liver hemangiomas, and 93 nonhemangiomatous benign lesions) in 235 patients (140 male and 95 female; mean age +/- SD, 56 +/- 11 years) who underwent CEUS after sulfur hexafluoride-filled microbubble injection. The digital cine clips recorded during the arterial (10-35 seconds…
Reproducible coronary plaque quantification by multislice computed tomography
2007
BACKGROUND: The aim of this study was to investigate reproducibility and accuracy of computer-assisted coronary plaque measurements by multislice computed tomography coronary angiography (QMSCT-CA). METHODS AND RESULTS: Forty-eight patients undergoing MSCT-CA and coronary arteriography for symptomatic coronary artery disease and quantitative intravascular ultrasound (IVUS, QCU) were examined. Two investigators performed the QMSCT-CA twice and a third investigator performed the QCU, all blinded for each other's results. There was no difference found for the matched region of interest (ROI) lengths (QCU 29.4 +/- 13 mm vs. QMSCT-CA 29.6 +/- 13 mm, P = 0.6; total length = 1,400 mm). The compari…
Idiopathic infantile asymmetry, proposal of a measurement scale
2004
Abstract To evaluate the development of idiopathic infantile asymmetry and the efficacy of therapeutic interventions, spinal scoliosis can be quantified on the basis of radiographs. For obvious reasons, use of this technique is limited. Here we present a clinical method to describe and quantify infantile asymmetry. For item selection, spontaneous movements (SMs), reactive movements (RMs) and length differences were video recorded in 30 infants (median age 10 weeks, range 6–16) with variable degrees of asymmetry. Within these three categories, reactive movements elicited by head turns to the right and left side in the prone and supine position emerged as reliable parameters reflecting trunk …