Gray's Dev. of GI Flashcards
A 4 y/o male child is admitted to the hospital with severe vomitting. Radiologic examination and history taking reveals that the boy suffers from an annular pancreas. Which of the following structures is most typically obstructed by this condition?
dorsal + ventral bud of pancreas fuse and obstruct the 2nd part of the duodenum
rotation of the stomach during development results in movement of the left vagus nerve from its original position. Through approx. how many degrees of rotation does the nerve move and what is its final position?
Parts of the tube rotate 270 degrees, but the prox. foregut, specifically the portion that forms the esophagus, rotates only 90 degrees. This rotation is counterclockwise, which brings the left vagus nerve onto the anterior surface of the esophagus.
A 2 day-old newborn male is cyanotic after attempts to swallow milk result in collection of the milk in his mouth. After 2 days he develops aspiration pneumonia. A tracheoesophageal fistula is suspected. Which of the following structures has most likely failed to develop properly?
The tracheoesophageal septum is the downgrowth that separates the ventral wall of the foregut (esophagus) from the laryngotracheal tube. The presence of a fistula would result in passage of fluid from the esophagus into the trachea and could cause aspiration pneumonia.
A 1-month old infant with billous vomiting and feeding intolerance is examined by the pediatric team. Imaing reveals malrotation of the small intestine without fixation of the mesenteries. The vessels around the duodenojejunal junction are obstructed and the intestine is at risk of becoming gangrenous. Which of the following has occurred to cause the obstruction?
Midgut volvulus is a possible complication of malrotation of the midgut loop without fixed mesentery. The small intestines twist around the vasculature that is providing support for them.
A 5 day old male infant is diagnosed with Hirschspring disease. CT scan examination reveals an abnormally dilated colon. Which of the following is the most likely embryologic mechanism responsible for Hirschspring disease?
Congenital megacolon (Hirschsprung’s disease) results from the failure of neural crest cells to migrate into the walls of the colon.
A 1-day old female infant has a mass protruding through her umbilicus. Physical examination reveals an umbilical hernia. A CT scan revelas that part of another organ is attached to the inner surface of the hernia. What portion of the GI tract is most likely attached to the inner surface of the umbilical hernia?
The ileum is the most common site of Meckel’s diverticulum. This outpouching is a persistence of the vitelline duct and can be attached to the umbilicus.
A 5 year old boy is admitted to the hospital with failure to thrive, dysphagia, and history of recurrent chest infections. 2 days later the boy develops aspiration pneumonia. Esophagogastric examination shows webs and structures in the distal third of the thoracic esophagus. Which of the following development conditions will most likely explain the symptoms?
Esophageal stenosis results from a failure of esophageal recanalization in the eighth week of development, which may also cause esophageal atresia. Webs and strictures are found in an examination of the esophagus in cases of stenosis, but they are not noticed in cases of atresia.
The vomit of a 5-day old infant contains stomach contents and bile. The vomitting has continued for 2 days. Radiographic examinations reveal stenosis of the 4th part of the duodenum. Which of the following development conditions does the child have?
Duodenal stenosis is caused by incomplete recanalization of the duodenum. The vomit contains bile because of the location of the occlusion, which is distal to the hepatopancreatic ampulla (of Vater) where the common bile duct enters the small intestine.
A 4 day old infant vomits the contents of his stomach but the vomit does not appear to contain bile. Which of the following conditions does the baby have?
Hypertrophy of the pyloric sphincter and the narrowing of the pyloric canal causes projectile vomiting of the stomach contents without bile because the bile enters the duodenum distal to the pyloric constriction.
The vomit of a 5 day old female infant contains stomach content and bile. Radiographic examination reveals stenosis of the 3rd part of the duodenum. Which condition does the child have?
Incomplete recanalization of the duodenum is caused either by duodenal stenosis or partial occlusion of the lumen of the duodenum and usually occurs in the distal 3rd portion of the duodenum.
A 2 hour old male infant had been diagnosed in utero with polyhydramnios. Now he is vomiting stomach contents and bile. Radiographic examination reveals a “double bubble”. What does the child have?
Duodenal atresia is the result of a failed reformation of the lumen of the duodenum and is associated with vomiting withint he first few days of birth. Polyhydramnios is seen due to abnomral absorption of amniotic fluid. Radiographic or ultrasound examination would reveal the “double bubble” sign because of distended, gas-filled stomach
A 4 year old male child is admitted to the hospital with severe vomitting. The boy suffers from annular pancreas. Which of the condition will explain the symptoms?
The bifid ventral bud fused with the dorsal bud. Annular pancreas causes a duodenal obstruction in the 2nd part of the duodenum.
A surgeon noted a 5-cm long fingerlike pouch on the anterior border of the ileum. This pouch is a remnant of which of the following structures?
A remnant of the omphaloenteric duct (yolk stalk) presents as an ileal (Meckel’s) diverticulum.
A 3 month old boy is admitted to the hospital with an abrnomal mass of tissue protruding from his abdomen. An MRI examination reveals that the mass contains greater omentum and some small intestine. The abnormal mass protrudes when the infant cries, strains and coughs. What condition does the child have?
An umbilical hernia results when the body wall doesn’t close appropriately at the site of attachment of the umbilical cord. In umbilical hernia, the herniating structures are covered by subcutaneous tissue and skin
Ultrasound examinations of a male fetus in the seventh month of gestation indicate a defect where the viscera protrude into the amniotic cavity. What condition?
Gastroschisis results from an incomplete closure of the lateral folds. This results in an epigastric hernia, with viscera that protrude into the amniotic cavity without a peritoneal covering and are covered by amniotic fluid.
