Intusussception is invagination one bowel segment into adjacent bowel
segment. Rare in adults.
Types - ileocolic, colocolic, enteroenteric, or jejunogastric.
Causes in adults are generally mechanical. Lead points involving colon are
usually malignant (carcinoma, lymphoma) and of small bowel tend to be benign
like lipoma, polyp, Meckel's diverticulum, sprue or from lymphoid hyperplasia
secondary to viral infection.
Gastrointestinal lipoma may be submucosal or subserosal. Intestinal
intussusception by lipoma is uncommon. Rare when lipoma located in small
intestine. Found in the ileum, duodenum and jejunum in decreasing order of
Adult intussusception is a rare disease and symptoms tend to be more chronic
or intermittent with vague abdominal pain, nausea and vomiting, abdominal
distension with partial obstruction, or palpable abdominal mass at physical
CT - Target like or sausage like mass, the inner central area represents the
invaginated intussusceptum surrounded by
its mesenteric fat and associated vasculature, all of which are surrounded by
the thick-walled intussuscipiens.If blood supply is compromised there
is thickening of bowel loops.
Ultrasonography- Multilayered appearance consisting of the alternating
hyperechoic and hypoechoic concentric rings that represent alternating layers of
mucosa, bowel wall, and mesenteric fat in cross section.