Multi-Level Visual Alphabets

A central debate in visual perception theory is the argument for indirect versus direct perception; i.e., the use of intermediate, abstract, and hierarchical representations versus direct semantic interpretation of images through interaction with the outside world. We present a content-based representation that combines both approaches. The previously developed Visual Alphabet method is extended with a hierarchy of representations, each level feeding into the next one, but based on features that are not abstract but directly relevant to the task at hand. Explorative benchmark experiments are carried out on face images to investigate and explain the impact of the key parameters such as pattern size, number of prototypes, and distance measures used. Results show that adding an additional middle layer improves results, by encoding the spatial co-occurrence of lower-level pattern prototypes

Residential mobility and local housing-market differences

The authors extend previous literature on variations in mobility rates across local housing markets by examining the linkage of mobility rates at the household level to the structure of local housing markets. The results suggest that residential mobility rates differ widely across local housing markets, substantiating the view that residential relocation is intimately intertwined with conditions at the local level. Local housing-market conditions also have different effects on mobility rates for renters and owner-occupiers. The results suggest that variation in residential mobility rates across housing markets can be in part explained by level of urbanization, the tenure structure, the degree of government intervention, and the size of the housing market. Remarkably, these differences in local housing markets cannot be seen to be related to housing-market features only. The results suggest that these differences can also be attributed to the behavior or attitude of households with respect to housing

Optimization of ERCP Technique to Improve the Sensitivity of Biliary Brushing: A Systematic Review and Meta-analysis

BACKGROUND AND AIMS: Endoscopic retrograde cholangiopancreatography (ERCP) with brush cytology is an important tool in the diagnosis of hepatobiliary malignancies. However, reported sensitivity of brush cytology is suboptimal and differs markedly per study. The aim of this study is to analyze the optimal technique of endobiliary brushing during ERCP. METHODS: A systematic review and meta-analysis according was performed using Pubmed, Embase and Cochrane library, and reported reported according to the PRISMA guidelines. The intervention reported should involve ERCP, performed by the endoscopist with a comparison of different brushing techniques. The primary outcome was sensitivity for malignancy. Studies published up to December 2022 were included. Percutaneous techniques and cytological or laboratory techniques for processing of material were excluded. Bias was assessed using the Quadas-2 tool. Pooled sensitivity rates and Forest plots were analyzed for the primary outcome. RESULTS: A total of 16 studies were included. Three studies reported on brushing before or after dilation of a biliary stricture. No improvement in sensitivity was found. Five studies reported on alternative brush designs. This did not lead to improved sensitivity. Seven studies reported on the aspiration and analysis of bile fluid, which resulted in a 16% increase in sensitivity (95% CI 4-29%). One study reported an increased in the number of brush passes to the stricture, providing an increase in sensitivity of 20%. Substantial heterogeneity between studies was found, both methodological and statistical. CONCLUSIONS: Increasing the number of brush-passes and sending bile fluid for cytology increases the sensitivity of biliary brushings during ERCP. Dilation before brushing or alternative brush designs did not increase sensitivity

Covered stents versus Bare-metal stents in chronic atherosclerotic Gastrointestinal Ischemia (CoBaGI): Study protocol for a randomized controlled trial

Background: Chronic mesenteric ischemia (CMI) is the result of insufficient blood supply to the gastrointestinal tract and is caused by atherosclerotic stenosis of one or more mesenteric arteries in > 90% of cases. Revascularization therapy is indicated in patients with a diagnosis of atherosclerotic CMI to relieve symptoms and to prevent acute-on-chronic mesenteric ischemia, which is associated with high morbidity and mortality. Endovascular therapy has rapidly evolved and has replaced surgery as the first choice of treatment in CMI. Bare-metal stents (BMS) are standard care currently, although retrospective studies suggested significantly highe

Multi-Level Visual Alphabets

A central debate in visual perception theory is the argument for indirect versus direct perception; i.e., the use of intermediate, abstract, and hierarchical representations versus direct semantic interpretation of images through interaction with the outside world. We present a content-based representation that combines both approaches. The previously developed Visual Alphabet method is extended with a hierarchy of representations, each level feeding into the next one, but based on features that are not abstract but directly relevant to the task at hand. Explorative benchmark experiments are carried out on face images to investigate and explain the impact of the key parameters such as pattern size, number of prototypes, and distance measures used. Results show that adding an additional middle layer improves results, by encoding the spatial co-occurrence of lower-level pattern prototypes

Validation study of automatically generated codes in colonoscopy using the endoscopic report system Endobase

OBJECTIVE: Gastrointestinal endoscopy databases are important for surveillance, epidemiology, quality control and research. A good quality of automatically generated databases to enable drawing justified conclusions based on the data is of key importance. The aim of this study is to validate the correctness of coding of a national automatically generated anonymous endoscopy database. MATERIAL AND METHODS: We evaluated a total of 500 colonoscopies performed in five larger hospitals of the TRANS.IT project focusing on endoscopy reporting. Randomly 500 examinations were selected from a total of 5,000 examinations and their generated endoscopic terminology codes as well as complete reports were analysed. Indications for the examination and described findings were scored for correctness and clinical relevance of the coding that would be exported to the anonymous database. RESULTS: Indications were correctly coded in 92% of all examinations (range 76-100%) per hospital. Correct coding of findings ranged from 42% to 93% per hospital (mean 77%). Different correct coding proportions were seen varying with the diagnosis, with the highest correct coding rates in polyps, carcinoma and diverticular disease. Incorrect coded examinations were scored for clinical relevance. Overall 11% of the investigated examinations were incorrectly coded with clinical relevance. CONCLUSIONS: Accuracy of clinically relevant endoscopy data recorded in the TRANS.IT anonymous central database is high. Further improvement is desirable, which may be achieved by education of individual endoscopists and enhancement of the progra

Continuous monitoring of colonoscopy performance in the Netherlands: First results of a nationwide registry

Background To optimize colonoscopy quality, several performance measures have been developed. These are usually assessed without distinction between the indications for colonoscopy. This study aimed to assess the feasibility of linking two national registries (one for colonoscopy and one for adverse events of gastrointestinal endoscopies in the Netherlands), and to describe the results of colonoscopy quality per indication. Methods This retrospective study was conducted with prospectively collected data of the Dutch Gastrointestinal Endoscopy Audit (DGEA) and the Dutch Registration of Complications in Endoscopy (DRCE). Data between 01-01-2016 and 01-01-2019 were analyzed. To calculate adverse event rates, data were linked at the level of endoscopy service. Results During the 3-year study period, 266 981 colonoscopies were recorded in DGEA. Of all indications, cecal intubation rate was highest in fecal immunochemical test (FIT)-positive screening colonoscopies (97.1%), followed by surveillance (93.2%), diagnostic (90.7%), and therapeutic colonoscopies (83.1%). The highest rate of adequate bowel preparation was observed in FIT-positive screening colonoscopies (97.1%). A total of 1540 colonoscopy-related adverse events occurred (0.58% of all colonoscopies). Bleeding and perforation and rates were highest for therapeutic (1.56% and 0.51%, respectively) and FIT-positive screening (0.72% and 0.06%, respectively) colonoscopies. The colonoscopy-related mortality was 0.006%. Conclusion This study describes the first results of the Dutch national colonoscopy registry, which was successfully linked to data from the national registry for adverse events of gastrointestinal endoscopies. In this large dataset, performance varied between indications. Our results emphasize the importance of defining benchmarks per indication in future guidelines