AIM To evaluate the ability of PillCamColon2 to visualize colonic segments missed by incomplete optical colonoscopy(OC) and to assess the diagnostic yield.METHODS This prospective multicentre study included 81 patient...AIM To evaluate the ability of PillCamColon2 to visualize colonic segments missed by incomplete optical colonoscopy(OC) and to assess the diagnostic yield.METHODS This prospective multicentre study included 81 patients from nine centres who underwent second-generation colon capsule endoscopy(CCE) following incomplete OC performed by an experienced gastroenterologist(> 1000 colonoscopies). Patients with stenosis were excluded. According to patient preferences, CCE was performed the following day(protocol A) after staying on clear liquids and 0.75 L Moviprep in the morning or within 30 d after new split-dose Moviprep(protocol B). Boosts consisted of 0.75 L and 0.25 L Moviprep, and phospho-soda was given as a rescue if the capsule was not excreted after seven hours.RESULTS Seventy-four patients were analysed(51% of them in group A; 49% in group B). Bowel cleansing was adequate in 67% of cases, and CCE could visualize colonic segments missed by incomplete colonoscopy in 90% of patients under protocol A and 97% of patients under protocol B(P = 0.35, n.s.). Significant polyps including adenocarcinoma were detected in 24% of cases. Detection rates for all polyps and significant polyps per patient were similar in both protocols. Polyps were found predominantly in the right colon(86%) in segments that were not reached by OC. Extracolonic findings-such as reflux esophagitis, suspected Barrett esophagus, upper GI-bleeding, gastric polyps, gastric erosions and angiectasia-were detected in eight patients. Pill Cam Colon2 capsule was retained in the ileum of one patient(1.4%) without symptoms and removed during an uneventful resection for unknown Crohn's disease that was diagnosed as the cause of anemia, which was the indication for colonoscopy. CCE was well tolerated. One patient suffered from selflimiting vomiting after consuming the phospho-soda.CONCLUSION Second-generation CCE using a low-volume preparation is useful after incomplete OC, and it allows for the detection of additional relevant findings, but cleansing efficiency could be improved.展开更多
Floor field methods are one of the most popular medium-scale navigation concepts in microscopic pedestrian simulators.Recently introduced dynamic floor field methods have significantly increased the realism of such si...Floor field methods are one of the most popular medium-scale navigation concepts in microscopic pedestrian simulators.Recently introduced dynamic floor field methods have significantly increased the realism of such simulations,i.e.agreement of spatio-temporal patterns of pedestrian densities in simulations with real world observations.These methods update floor fields continuously taking other pedestrians into account.This implies that computational times are mainly determined by the calculation of floor fields.In this work,we propose a new computational approach for the construction of dynamic floor fields.The approach is based on the one hand on adaptive grid concepts and on the other hand on a directed calculation of floor fields,i.e.the calculation is restricted to the domain of interest.Combining both techniques the computational complexity can be reduced by a factor of 10 as demonstrated by several realistic scenarios.Thus on-line simulations,a requirement of many applications,are possible for moderate realistic scenarios.展开更多
文摘AIM To evaluate the ability of PillCamColon2 to visualize colonic segments missed by incomplete optical colonoscopy(OC) and to assess the diagnostic yield.METHODS This prospective multicentre study included 81 patients from nine centres who underwent second-generation colon capsule endoscopy(CCE) following incomplete OC performed by an experienced gastroenterologist(> 1000 colonoscopies). Patients with stenosis were excluded. According to patient preferences, CCE was performed the following day(protocol A) after staying on clear liquids and 0.75 L Moviprep in the morning or within 30 d after new split-dose Moviprep(protocol B). Boosts consisted of 0.75 L and 0.25 L Moviprep, and phospho-soda was given as a rescue if the capsule was not excreted after seven hours.RESULTS Seventy-four patients were analysed(51% of them in group A; 49% in group B). Bowel cleansing was adequate in 67% of cases, and CCE could visualize colonic segments missed by incomplete colonoscopy in 90% of patients under protocol A and 97% of patients under protocol B(P = 0.35, n.s.). Significant polyps including adenocarcinoma were detected in 24% of cases. Detection rates for all polyps and significant polyps per patient were similar in both protocols. Polyps were found predominantly in the right colon(86%) in segments that were not reached by OC. Extracolonic findings-such as reflux esophagitis, suspected Barrett esophagus, upper GI-bleeding, gastric polyps, gastric erosions and angiectasia-were detected in eight patients. Pill Cam Colon2 capsule was retained in the ileum of one patient(1.4%) without symptoms and removed during an uneventful resection for unknown Crohn's disease that was diagnosed as the cause of anemia, which was the indication for colonoscopy. CCE was well tolerated. One patient suffered from selflimiting vomiting after consuming the phospho-soda.CONCLUSION Second-generation CCE using a low-volume preparation is useful after incomplete OC, and it allows for the detection of additional relevant findings, but cleansing efficiency could be improved.
文摘Floor field methods are one of the most popular medium-scale navigation concepts in microscopic pedestrian simulators.Recently introduced dynamic floor field methods have significantly increased the realism of such simulations,i.e.agreement of spatio-temporal patterns of pedestrian densities in simulations with real world observations.These methods update floor fields continuously taking other pedestrians into account.This implies that computational times are mainly determined by the calculation of floor fields.In this work,we propose a new computational approach for the construction of dynamic floor fields.The approach is based on the one hand on adaptive grid concepts and on the other hand on a directed calculation of floor fields,i.e.the calculation is restricted to the domain of interest.Combining both techniques the computational complexity can be reduced by a factor of 10 as demonstrated by several realistic scenarios.Thus on-line simulations,a requirement of many applications,are possible for moderate realistic scenarios.
