The End

AO: appendiceal orifice; ICV: Ileocecal valve

AO: appendiceal orifice; ICV: Ileocecal valve

I must inform you that this is the end of the line.  To a gastroenterologist, seeing these images during a colonoscopy signifies that the end of the colon has been reached.  The more challenging portion of the procedure is over, and now the withdrawal phase begins, where the scope is slowly and methodically pulled back and every nook and cranny is explored for pathology.

The image to the left labeled AO refers to the appendiceal orifice, and this is usually a slit-like opening or a boomerang shape as seen above.  It is where the appendix is attached to the colon.  It can sometimes look a little flat if the patient had the appendix removed, but usually still remains visible.  The image to the right labeled ICV is the ileocecal valve, which is the attachment of the ileum (the last part of the small intestine) to the cecum (the end of the colon.)  Seeing both of these landmarks ensures with 100% certainty that the scope has reached the cecum, which is only one of two points during a colonoscopy where the endoscopist knows exactly where the tip of the scope is (the other area being the rectum, where the scope is inserted.)

It is like driving through the Midtown Tunnel to Manhattan…if you make the drive frequently you sort of know where you are at any given time, but you wouldn’t bet on declaring your exact location with 100% certainty.  Only when you see the light at the end of the tunnel are you truly sure you’ve reached the city.  Seeing the cecal landmarks is almost as exciting!

Expert endoscopists are able to reach the cecum and complete a colonoscopy >95% of the time in healthy patients presenting for screening colonoscopy.  Not only must the cecum be reached and intubated (the tip of the scope actually placed in the cecum), but this must be photographed similar to what you see above.  We need to prove that we reached the cecum and visualized the entire colon.  Don’t be afraid to ask to see pictures of your cecum after your next colonoscopy!

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Rex DK, Schoenfeld PS, Cohen J, et al. Quality indicators for colonoscopy. Am J Gastroenterol 2015;110:72-90.