View clinical trials related to Colorectal Polyps.
Filter by:Recent studies have shown that narrow-band imaging (NBI) is a powerful diagnostic tool for the differentiation between neoplastic and non-neoplastic colorectal polyps. The aim of the present study is to develop and evaluate a computer-based method for automated classification of small colorectal polyps on the basis of vascularization features.In a prospective study 207 polyps with a size of 10mm or smaller should be detected by a zoom NBI colonoscopy. These polyps were imaged and subsequently removed for histological analysis. the polyp images were analyzed by a computer algorithm. The proposed computer-based method consists of several steps: preprocessing, vessel segmentation, feature extraction and classification. The results of the automatic classification (sensitivity, specificity, negative predictive value, positive predictive value and accuracy)were compared to those of human observers, who were blinded to the histological gold standard.
Standard white light endoscopy involves the passage of a thin, flexible camera into the colon from the anus. Although standard white light endoscopy can detect most polyps and precancerous areas in the gastrointestinal tract and colon, many studies have shown that even the most experienced doctors, under optimal conditions, can miss up to 15-25% of precancerous areas. Thus, there remains a clear need to develop new methods of improving standard white light endoscopy. We are investigating whether indocyanine green (ICG) can serve to highlight areas which are precancerous when the colon is visualized with a special cameral which shines fluorescent light. Information from other studies suggests that this ICG agent may help to visualize blood vessels flowing to precancerous areas in the colon. We are looking at the ability of ICG, in combination with an endoscope which shines fluorescent light, to visualize precancerous areas in the colon.
Colonoscopy is not a perfect test. It misses a substantial number of neoplastic lesions and has some risk of missing cancer. Nearly all work on detection during colonoscopy has focused on the withdrawal phase of the examination. This randomized, controlled trial will compare the additional effect on the rate of adenoma detection of mucosal inspection during colonoscope insertion, with inspection during instrument withdrawal, in patients undergoing colonoscopy for colorectal cancer screening or surveillance.
High quality bowel cleaning preparation was most important prerequisites of a accurate colonoscopy, because even a small amount of residual fecal matter can obscure small polyps and increase unnecessary procedure time. Until now, several studies evaluated the impact of bowel preparation on the quality of colonoscopy using comparison of the polyp detection rate in patients with adequate bowel preparation status to that in patients with inadequate bowel preparation status during colonoscopy. However, there was no direct measurement the effect bowel preparation status on the polyp missing rate, the quality of colonoscopy, using tandem colonoscopic evaluation in prospective setting.
Prospective study of accuracy of colonic polyp characterisation in vivo using high resolution white light endoscopy, narrow band imaging and chromoendoscopy.
The purpose of this study is to evaluate the efficacy of the new RJ4 compare with the standard RJ3 biopsy forceps for performing polypectomy for small colorectal polyps.
The purpose of this study is to evaluate prospectively the usefulness of IC-CO2(intraoperative colonoscopy (IC) using carbon dioxide (CO2)) in colon and rectal surgical practice, coincident with laparoscopic surgery, and assess whether it provides useful information that influences the type of surgical therapy intended. Investigators will further define the safety and extent of bowel distension when using IC-CO2.
A database has been established to track the outcomes of all cases performed in the University Hospitals Department of Surgery in an effort to improve quality of surgical performance and case management. Specifically, the purpose of the database will be used as a quality improvement tool for analyzing process and outcome measures and to accurately track cases performed by surgeons.
The researchers are involved in a research program to understand how vitamin D and calcium in the diet or as supplements may lower the risk of colorectal polyps and cancer. To that end, the researchers are conducting a study of vitamin D supplementation in which volunteer subjects are provided a Western style diet for 2 separate 4 week periods at the Rockefeller University Hospital. During one of these 4 week inpatient periods, subjects receive calcium supplements and during the other 4 week inpatient period they receive a placebo tablet. The researchers determine changes within the colon as a result of supplementing the vitamin D in the presence of high and low calcium. A more detailed description of the study is provided below.
This study involves a primary VC screening for colorectal polyps. The research hypothesis is that VC screening, including surveillance of sub-cm polyps, is a safe and effective approach.