Purpose: To determine the clinical, radiologic, and pathologic findings of inverted Meckel diverticulum by retrospectively reviewing a large series of cases.
Materials and methods: Among 84 cases of Meckel diverticulum, 18 (21%) were found at surgery to be inverted into the lumen of the bowel. Thirteen of these 18 (72%) cases were associated with small bowel intussusception and five (28%) were not.
Results: All 18 patients (median age at time of diagnosis, 32 years) were symptomatic, but the symptoms were subacute or chronic in 14 (78%). At barium examination in 15 cases, inverted diverticulum was depicted in 10 (67%) as a solitary, elongated, smoothly marginated, often club-shaped intraluminal mass in the distal ileum. At computed tomography (CT) in three cases, a central area of fat attenuation was surrounded by a thick collar of soft-tissue attenuation. At ultrasound (US) in two cases, a target-like mass contained a central area of increased echogenicity. At pathologic examination in all cases, the inverted sac contained mesenteric fat.
Conclusion: Inverted Meckel diverticulum occurs more commonly than previously recognized and is associated with characteristic findings at barium examination, CT, and US.