Endoscopists using the water-infusion method of screening colonoscopy found significantly more adenomas if they added indigo dye, compared with the water method alone, a new study has shown. "Indigo carmine enhances any surface irregularities" when used as part of screening colonoscopies, Dr. Joseph W. Leung said in a late-breaking abstract session at the annual meeting of the American College of Gastroenterology.
Indigo carmine is used to enhance adenoma (polyp) detection in chromo-endoscopy, which is a more cumbersome process than the water method, Dr. Leung said. He and his colleagues at the Sacramento VA Medical Center in Mather, California conducted a randomized, controlled trial to assess the value of adding indigo carmine to the water method. The colonoscopies were performed by two endoscopists who had experience with both methods. Patients were blinded as to which procedure they had, and all patients underwent intravenous conscious sedation. In both groups, air was suctioned out of the rectum to remove any fecal material and stool or cloudiness was suctioned out, followed by another infusion of clear water. Apparently colon preparation and surface enhancing play an important role in adenoma detection.
Early detection of a polyp is critical because polyps evolve to cancer over time, and if not resected can metastasize and result in death. Colonoscopy evaluations have a low but significant false negative rate, and repeat colonoscopies may sometimes detect undiagnosed but pre-existing adenomas. In high risk patients or symptomatic patients, however, a single colonoscopy may be the only chance to detect an adenoma before it becomes cancerous. Therefore, when doing a colonoscopy it is important to utilize the best available technique to detect these potentially lethal abnormalities. A patient can ask the physicians performing the study how they plan to do the study and how that method enhances detection. Failure to detect may be based on failure to adhere to available guidelines or using outmoded techniques.
Stein, Mitchell, and Muse, LLP has successfully handled numerous cases of undiagnosed cancer following failed colonoscopy procedures. Our experienced medical malpractice team is available at (202) 737-7777 for a free, no obligation consultation.
