PAEA Surgery End Of Rotation (EOR) Practice Exam

Which congenital anomaly is a remnant of the embryonic vitelline/omphalomesenteric duct?

1. Meckel's diverticulum

2. Hirschsprung's disease

3. Gastroschisis

4. Intestinal malrotation

The correct answer is: Meckel's diverticulum

Meckel's diverticulum is a congenital anomaly that arises from the incomplete closure of the embryonic vitelline or omphalomesenteric duct. During fetal development, this duct connects the yolk sac to the midgut, allowing for nutrient absorption. In most cases, this duct completely obliterates by the 7th week of gestation. However, if it does not close properly, it can leave behind a diverticulum, which is typically located about 2 feet from the ileocecal junction of the small intestine. Meckel's diverticulum is generally asymptomatic but can occasionally lead to complications such as gastrointestinal bleeding, intestinal obstruction, or even inflammation mimicking appendicitis due to the presence of ectopic gastric or pancreatic tissue within the diverticulum. In contrast, Hirschsprung's disease is characterized by the absence of ganglion cells in a segment of the colon, leading to functional obstruction. Gastroschisis refers to a defect in the abdominal wall where the intestines protrude outside the body, and intestinal malrotation involves abnormal positioning of the intestines, which can lead to volvulus but is not directly related to the vitelline duct.