Meckel Diverticulum

  • Etiology: persistent remnant of omphalomesenteric (vitelline) duct which runs in umbilical cord connecting primitive midgut (terminal ileum) and extraembryonic sac that involutes by 6th week
  • Meckel scan: shows simultaneous appearance of radiotracer in stomach + diverticulum as ~ 50% contain ectopic gastric mucosa, negative Meckel scan does not rule out Meckel diverticulum
  • US: cystic lesion near distal ileum or in periumbilical location
  • CT: on antimesenteric border of small bowel
  • Complications: hemorrhage due to acid secretion / ulceration
  • Clinical: can present with lower gastrointestinal bleed or small bowel obstruction, rule of 2: in 2% of population / is 2 feet from ileocecal valve / 2% get complications / complications occur before 2 years old

Radiology Cases of Meckel Diverticulum

Meckel’s scan of Meckel's diverticulum
AP delayed image (left) from a Tc-99m pertechnetate scan (Meckel scan) shows a focal round concentration of radiotracer in the right lower quadrant superior and lateral to the midline bladder which is seen in the middle of the lower abdomen superior to the bladder on the lateral (right) delayed image.
CT of small bowel obstruction due to Meckel's diverticulum
AXR supine (upper left) and coronal CT with contrast of the abdomen (lower left) show multiple dilated loops of small bowel with thin walls throughout the abdomen. The lower axial CT (upper right) shows a small cystic structure in the midline with a thicker wall than the surrounding dilated bowel which is also seen on the midline sagittal CT (lower right) just beneath the umbilicus.

Surgery Cases of Meckel Diverticulum

Surgical image of Meckel diverticulum
Surgical image shows dilatation of almost the entire small bowel except for the decompressed terminal ileum in the left lower corner of the photograph. At this transition point, a diverticulum is noted on the anti-mesenteric border of the ileum.
Surgical image of Meckel's diverticulum
Surgical image shows shows multiple dilated loops of small bowel in the background with a sharp transition point seen in the center of the image in the terminal ileum where on its anti-mesenteric border a diverticulum is seen with an omphalomesenteric duct remnant coming off it. This remnant had been attached to the under surface of the umbilicus, serving as a fulcrum for a small bowel volvulus, resulting in a small bowel obstruction.