| Abstrakt: |
In 1809, the German anatomist Johann Meckel the Younger described the structure that now bears his name and postulated its embryologic origin. The embryonic midgut is connected ventrally to the yolk sac via the vitelline duct, also known as the omphalomesenteric or omphaloenteric duct. Normally regressing between the fifth and seventh weeks of gestation, persistence of a portion of the vitelline duct on the antimesenteric side of the intestine results in one of several anomalous structures either alone or in combination. Meckel΄s diverticulum is probably the most common, but others include vitelline sinuses, cysts, fibrous cords from the intestine to umbilicus, and omphaloenteric fistulas. The right and left vitelline arteries originate from the primitive dorsal aorta and travel with the omphalomesenteric duct. The left involutes while the right becomes the superior mesenteric artery and provides a terminal branch to the diverticulum. Obliterated vitelline artery remnants can persist as fibrous bands from the mesentery to the abdominal wall, providing a potential focus of volvulus or obstruction. [ABSTRACT FROM AUTHOR] |
