Intussusception (medical disorder)

An intussusception is a situation in which a part of the intestine has prolapsed into another section of intestine, similar to the way in which the parts of a collapsible telescope slide into one another. The part which prolapses into the other is called the intussusceptum, and the part which receives it is called the intussuscipiens. The most frequent type of intussusception is one in which the ileum enters the cecum, however other types are known to occur, such as when a part of the ileum or jejunum prolapses into itself. Almost all intussusceptions occur with the intussusceptum having been located proximally to the intussuscipiens. The reason for this is that peristaltic action of the intestine pulls the proximal segment into the distal segment. There are, however, rare reports of the opposite being true.
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