Intussusception, Section of the Small Intestine

Description

Intussusception is illustrated in a sectioned segment of small intestine, where a proximal bowel loop (intussusceptum) telescopes into the lumen of the adjacent distal segment (intussuscipiens). The invaginated bowel wall forms concentric layers, with mucosa and submucosa folded centrally and the muscularis externa and serosa reflected around them, creating a collar-like cuff at the point of entry. Along the mesenteric border, the dragged mesentery is implied as a wedge of compressed tissue between the layers, a relationship that places mesenteric vessels medial to the receiving bowel wall and vulnerable to kinking. Lumen caliber narrows at the neck. Clinically, this configuration explains the classic obstructive pattern of intermittent pain and progressive vomiting, because luminal occlusion and venous congestion begin at the constricted neck before arterial compromise develops. The mesenteric entrapment is the key. Edema, hemorrhage into the wall, and eventual ischemia can follow, matching the risk of bloody stools and peritonitis when strangulation occurs; the illustration supports correlation with ultrasound “target” and “pseudokidney” appearances and with operative findings during manual reduction or bowel resection. For teaching, the fixed sectional perspective makes it easy to trace which layers belong to the entering segment versus the receiving segment, a frequent source of confusion when discussing lead points such as Meckel diverticulum, polyps, or lymphoid hyperplasia. Use this illustration in gastrointestinal pathology lectures, pediatric surgery teaching files, radiology-pathology correlation figures, and patient-education materials explaining intussusception reduction and ischemic risk in a concrete, layer-by-layer way. Anatomical accuracy verified by SciePro's Medical Advisory Board.