Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content +++ 1. Melanosis ++ Graphic Jump LocationView Full Size||Download Slide (.ppt) Figure 1 Melanosis coli refers to the dark pigmentation of the colonic mucosa in patients taking anthracene-containing laxatives. While this pigmentation is harmless, it is a clue to the patient's chronic cathartic laxative use. +++ 2. Polyp in Setting of Melanosis Coli ++ Graphic Jump LocationView Full Size||Download Slide (.ppt) Figure 2 The melanosis pigment is not taken up by adenomatous tissue, so detection of adenomatous polyps in the background setting of melanosis coli can make polyp detection easier, as evidenced here. +++ 3. Hypertrophied Papilla (A) ++ Graphic Jump LocationView Full Size||Download Slide (.ppt) Figure 3 Fleshy white protuberances appearing at the anorectal junction, as often seen best on retroflexion view of the region, are benign post inflammatory lesions that are not clinically significant. These should not be confused with polyps, and do not require removal. +++ 4. Hypertrophied Papilla (B) ++ Graphic Jump LocationView Full Size||Download Slide (.ppt) Figure 4 Hypertrophied papillae, as seen here, are generally multiple, whiteish yellow in appearance, and irregular in shape, making them distinguishable from polyps. +++ 5. Volvulus below Obstruction ++ Graphic Jump LocationView Full Size||Download Slide (.ppt) Figure 5 A sigmoid volvulus presents as an acute colonic obstruction, most often in the sigmoid colon. Here, the colon has a “candy wrapper” twist, causing an obstruction, with colonic dilatation proximal to this region. With gentle pressure, the colonoscope can be advanced through this region in order to decompress the region more proximally. However, this generally provides only temporary relief of the obstruction, as opposed to a permanent solution preventing future occurrence of the volvulus. +++ 6. Volvulus above Obstruction ++ Graphic Jump LocationView Full Size||Download Slide (.ppt) Figure 6 It is generally easy to discern when the scope is above the region of the sigmoid volvulus. The colon is generally dilated from air and stool filled, causing the lighting of the region to be diminished, and an overall dim appearance. +++ 7. Acute Colitis of the Colon, Clostridium difficile ++ Graphic Jump LocationView Full Size||Download Slide (.ppt) Figure 7 An acute infection with Clostridium difficile will cause an acute colitis of the colon. The hallmark lesions are whitish yellow exudative lesions, which on histologic examination have a characteristic “volcano eruption” appearance. +++ 8. Acute Colitis of the Colon, Clostridium difficile, Typical Appearance ++ Graphic Jump LocationView Full Size||Download Slide (.ppt) Figure 8 Typical appearance of C. difficile colitis. Following antibiotic therapy, the colonic mucosa will appear normal. +++ 9. Diverticulosis ++ Graphic Jump ... Your Access profile is currently affiliated with [InstitutionA] and is in the process of switching affiliations to [InstitutionB]. Please select how you would like to proceed. Keep the current affiliation with [InstitutionA] and continue with the Access profile sign in process Switch affiliation to [InstitutionB] and continue with the Access profile sign in process Get Free Access Through Your Institution Learn how to see if your library subscribes to McGraw Hill Medical products. Subscribe: Institutional or Individual Sign In Error: Incorrect UserName or Password Username Error: Please enter User Name Password Error: Please enter Password Sign in Forgot Password? Forgot Username? Download the Access App: iOS | Android Sign in via OpenAthens Sign in via Shibboleth You already have access! Please proceed to your institution's subscription. Create a free profile for additional features.