By the way, doctor: Does a colonoscopy reach the ileum?

Q. I am scheduled to have a colonoscopy soon. Does the examination reach the ileum?

A. The ileum is the last 12 feet or so of the small intestine. It connects to the cecum, the bulbous cul-de-sac that forms the beginning of the colon (the appendix hangs off the cecum). Space is at a premium in our abdomens, so the ileum and the rest of the small intestine are folded up and tucked inside the archway created by the colon's ascending, transverse, and descending sections.