Colonoscopy: Advanced and Emerging Techniques—A Review of Colonoscopic Approaches to Colorectal Conditions

Abstract

).A complete colonoscopy is key in the diagnostic and therapeutic approach to many, if not most, colorectal diseases. Its role in reducing incidence and mortality from colorectal cancer is well known. The American College of Gastroenterology (ACG) provides guidelines to achieving critical aspects of effective and complete colonoscopies. As colorectal surgeons who may also offer screening colonoscopy in our breadth of clinical services, we should hold ourselves accountable to the quality measures set by the ACG. Targets include cecal intubation rates of 95%, adenoma detection rates of 30% in men and 20% in women older than 50 years, and withdrawal time of at least 6 minutes.1 Higher completion rates correlate with a lower risk of interval colorectal cancer. Major challenges to colonoscopy are incomplete polyp removal and missed polyps, particularly in the setting of a difficult colonoscopy. This is especially true regarding serrated polyps that are quite often difficult to detect and therefore are missed or are incompletely removed.2 The missed adenoma rate for lesions 5 mm is 27%, 6 to 9 mm is 13%, 10 mm is 6%, and advanced adenoma is 11%.3 The rate of interval cancers, as defined by colorectal cancers diagnosed within 5 years of a negative colonoscopy, is related to the quality of the index colonoscopy. Missing polyps account for most of those cases, followed by incomplete removal. 2 A smaller percentage occurs in those patients who are genetically susceptible. 2,4There are a variety of well-established and newer techniques developed to optimize polyp detection, to perform complete polypectomy, and to endoscopically treat various complications and conditions, such as strictures and perforations. The objective of this article is to familiarize the colorectal surgeon with techniques utilized by both gastroenterologists and surgeons. The first part of this article will provide the colorectal surgeon who performs screening and diagnostic colonoscopies tips and tricks for cecal intubation and polyp detection. The second focus of this article will be on therapeutic and advanced endoscopic techniques, such as endomucosal resection (EMR), endoscopic submucosal dissection (ESD), and endoscopic options to treat colonic strictures and perforations. Maximizing Polyp Detection Rates Navigating the Difficult ColonBriefly, the elementary tips in colonoscopy include avoidance of pushing against resistance, recognizing and reducing loops, use of CO 2 insufflation when possible, and anticipation of the difficult case. Past medical history of substance abuse or previous high sedation requirements may provide insight on how to sedate the patient adequately for a successful exam. Useful maneuvers for patients with redundant, tortuous colons include stiffening the scope, use of abdominal AbstractA complete colonoscopy is key in the diagnostic and therapeutic approaches to a variety of colorectal diseases. Major challenges are incomplete polyp removal and missed polyps, particularly in the setting of a difficult colonoscopy. There ar...