Anal atresia and anorectal malformations I ntestinal obstructions are the most common surgical emergencies in the neonatal period. Early and accurate diagnosis of intestinal obstruction is paramount for proper patient management. For evaluation and diagnosis, intestinal obstruction in neonates can be divided into either high or low obstruction on the basis of the number of dilated bowel loops present on the initial abdominal radiographs. Although three or fewer dilated bowel loops are typically seen with high intestinal obstruction, more than three are generally seen with low intestinal obstruction in neonates. High intestinal obstructions are defined as occurring proximal to the ileum, resulting in various combinations of gastric, duodenal, and jejunal dilatation according to the level of obstruction (Table 1). In contrast, low intestinal obstructions involve the distal ileum or colon and typically result in diffuse dilatation of multiple small-bowel loops (Table 1). Although neonates with classic radiographic findings of high intestinal obstruction, such as duodenal atresia, may directly undergo surgery without any additional imaging, an upper gastrointestinal series is typically performed for further evaluation. Similarly, an enema examination is used for further investigation of low intestinal obstruction in neonates.