Diverticula

Description

Prominent mucosal and submucosal outpouchings (diverticula) project through the colonic muscularis propria, creating multiple rounded sacs along the bowel wall. Several diverticular necks are positioned between adjacent taeniae coli, where the vasa recta penetrate the circular muscle layer, a typical site for acquired (false) diverticula. The colonic lumen remains central, while the serosal surface bulges outward at each pouch. Small openings. Obvious. Attention to these relationships matters because diverticulosis most often clusters in the sigmoid colon, where higher intraluminal pressures and the segmental arrangement of circular muscle promote herniation at vascular entry points. When a diverticulum becomes obstructed by inspissated stool (fecalith), microperforation and pericolic inflammation follow, producing diverticulitis with fat stranding on CT and the familiar left lower quadrant pain pattern. The same anatomy explains brisk lower gastrointestinal bleeding when a vasa recta is eroded at the dome of a diverticulum, often without concurrent diverticulitis, and it clarifies why perforation tracks toward the mesocolon and peritoneal reflections rather than back into the lumen. Use this illustration for GI and general surgery teaching on diverticular disease, for radiology-pathology correlation in CT or colonoscopy-based modules, and for patient education materials explaining why dietary fiber, antibiotics, drainage, or segmental colectomy are recommended in different scenarios. It also fits well in journal figures discussing complications such as abscess, fistula, and stricture, or operative landmarks during sigmoid colectomy and primary anastomosis. Anatomical accuracy verified by SciePro's Medical Advisory Board.