[Gastrointestinal Emergencies in Neonates: What We Should Know]

Abstract

Newborn gastrointestinal tract emergency diseases include various disorders that occur anywhere along the digestive tract. Most of them are congenital malformations, not acquired diseases. Many of them cannot be confirmed on prenatal examination, and consequently, postnatal evaluation is required. Unlike adults, in newborn babies, detailed evaluations with computed tomography (CT) and magnetic resonance imaging (MRI) are often limited, so making the diagnosis based on early abdominal radiography is most important. Therefore, it is necessary to be familiar with the radiologic findings that may be seen on imaging studies. In addition, it is important to understand abdominal ultrasound and fluoroscopy findings, which can be used in addition to simple radiography and indications that can be used for further diagnosis and appropriate treatment. Therefore, this study describes and organizes the various imaging findings that may occur in neonatal gastrointestinal emergencies.

Fig. 1. Cases of 2-day-old male neonates with esophageal atresia: comparison between esophageal atresia with and without tracheoesophageal fistula.

A, B. Note kinking of the inserted orogastric tube within the proximal esophageal pouch in both (A) and (B). Note that the presence of stomach gas (arrow) defines the presence of the tracheoesophageal fistula (A). Non-delineable stomach gas defines the absence of the tracheoesophageal fistula (B).

Fig. 2. A 5-day-old male neonate with esophageal atresia: complained of repetitive aspiration and desaturation during feeding.

A. Repetitive pneumonic consolidation is noted in both the perihilar areas on a simple chest radiograph. B. During esophagography, there is an oblique fistulous tract (arrow) connecting the esophagus and trachea. It is diagnosed as a H-type tracheoesophageal fistula.

Fig. 3. Evaluation of the distal esophageal pouch level after gastrostomy in esophageal atresia patients.

A, B. Reflux of air (A) or contrast material (B) within the distal esophageal pouch (arrows) is noted during sucking of a pacifier.

Fig. 4. Postoperative complications of esophageal atresia.

A. Postoperative stenosis at the anastomosis level (arrow). B. Sliding hernia due to the stretched gastroesophageal junction above the diaphragm. C. Postoperative stenosis at the anastomosis level (arrow) with another stenosis at the distal esophagus (dot arrow) suggest the coexistence of esophageal stenosis.

Fig. 5. A 3-year-old boy with esophageal stenosis manifesting as vomiting after food ingestion.

A. During esophagography, there is stenosis at the distal esophagus with an impacted bean (arrow), which is noted as a filling defect. B. During follow-up esophagography after removal, there is linear outpouching staining (dot arrow) at the stenotic level (arrow) suggesting an underlying tracheobronchial remnant.

Fig. 6. A 10-month-old girl with malrotation, who has a mildly distended abdomen without vomiting.

A. There is a nonspecific bowel gas pattern. A relatively small bowel gas-like shadow is noted in the rightsided abdomen, and large bowel gas-like shadow is noted in the left-sided abdomen. B. Reversed SMA (A) and SMV (V) relations are noted on ultrasonography. C. Normal upper gastrointestinal series, for comparison. D. In the upper gastrointestinal series, the duodenal C-loop is noted at the normal location, on the right side to the right pedicle. However, the duodenojejunal junction (arrow) shows a medial location, and jejunum courses to the right upper quadrant abdomen area (dot arrow). SMA = superior mesenteric artery, SMV = superior mesenteric vein

Fig. 7. A 3-day-old male neonate with midgut volvulus manifesting as massive vomiting.

A. On a simple radiograph, the distended stomach and duodenal bulb show the “double bubble sign.” B. The typical “whirling sign” is noted on ultrasonography. The SMV (V), bowel, and bowel mesentery show whirling around the SMA (A), strongly suggesting volvulus. C. In the upper gastrointestinal series, the duodenum and jejunum show a spiral appearance in the right upper quadrant of the abdomen, which shows the “cock screw sign.” SMA = superior mesenteric artery, SMV = superior mesenteric vein

Fig. 8. A female neonate at birth with duodenal atresia.

A. The typical “double bubble sign” is noted on a simple radiograph. B. On ultrasonography, there is a distended duodenal bulb (D) with a non-delineable, collapsed 3rd portion of the duodenum. C. There is also wall thickening of the common bile duct (arrow), suggesting cholangitis.

Fig. 9. A 2-day-old female neonate with duodenal stenosis and a distended abdomen.

A. On a simple radiograph, a relatively distended stomach and duodenal bulb are noted. Gas passage to the distal small and large bowel loop is noted. B, C. In the upper gastrointestinal series and ultrasonography, the distended duodenum (D) and thin web-like structure (arrows) are delineated.

Fig. 10. A female neonate at birth with jejunal atresia.

A. The typical “triple bubble sign” is noted. B. On ultrasonography, there is a distended duodenum (D) and proximal jejunum (J) with non-delineable, collapsed other small bowel loops. Normal relations of superior mesenteric artery (A) and superior mesenteric vein (V) are also noted.

Fig. 11. A 2-day-old male neonate with ileal atresia.

A. On a simple radiograph, distended small bowel loops show the “multiple bubble sign.” A bulbous dilated segment (arrow) is noted at the lower abdomen. B. In the lateral view, rectal gas is not noted. At this point, Hirschsprung's disease is hard to differentiate. C. During enema, by using a water-soluble contrast material, decreased diameter of the colon loop is noted, which suggests an unused microcolon. D. Dilated fluid-filled small bowel loops with a collapsed unused microcolon (arrow) can also be noted on ultrasonography.

Fig. 12. female neonate at birth with healed-type meconium peritonitis who does not have specific symptoms.

A, B. Calcification (arrows) along the liver is noted on both simple radiograph and ultrasonography. Note the absence of a definite abnormal bowel gas pattern. These findings can be seen in healed-type meconium peritonitis.

Fig. 13. A male neonate at birth with meconium pseudocyst and a distended abdomen.

A. On a simple radiograph, a space occupying lesion (arrow) is noted in the lower abdominal area. B. A cystic lesion with a peripheral echogenic calcification and inner echogenic dirty debris are noted in the lower abdomen area on ultrasonography.

Fig. 14. A male neonate at birth with meconium peritonitis.

A. The distended abdomen with ascites is noted on a simple radiograph. A lucent area in the mid upper portion of the abdomen (arrows) suggests pneumoperitoneum. B, C. Echogenic debris within the ascites is noted in the whole abdominal area with bowel thickening (B), suggesting a “snowstorm appearance.” Ascites passage through the inguinal canal to the scrotal sac is also noted (C).

Fig. 15. A 2-day-old female preterm neonate with meconium obstruction of prematurity. She is a 28-week preterm neonate with a body weight of approximately 1.1 kg at the initial examination.

A. A simple radiograph on the 3rd day after birth shows distended bowel loops. B. On ultrasonography, a hypoechoic meconium within large bowel loops is revealed. C. On the 6th day after birth, water-soluble contrast enema was performed. A post-procedure simple radiograph shows contrast material filling of the distal small bowel loops with filling defects due to meconium.

Fig. 16. Ultrasonography of anorectal malformation cases with the transperineal approach.

A. A low-type anorectal malformation: a hypoechoic fistulous tract (arrow) at the skin to the anus (A) is noted. There is no connection between fistulous tract and bulbar urethra (U). B. An intermediate-type anorectal malformation: a hypoechoic fistulous tract (arrow) between the rectum (R) and the bulbar urethra (U) is noted. C. A high-type anorectal malformation: a hypoechoic fistulous tract (arrow) between the rectum (R) and the upper vagina (V) is noted.

Fig. 17. A male neonate with multiple anomalies (VACTERL association) associated with a high-type anorectal malformation.

A. Sacral deformity (arrow) is noted with distended bowel loops due to distal obstruction. B. A hypoechoic fistula (arrow) between the rectum (R) and the prostatic urethra (U) suggests a high-type anorectal malformation. C. Coarctation of the aorta is noted with a large PDA (arrow). D. Esophageal atresia is noted with kinking of the orogastric tube (arrow). E. A single right kidney is noted on MRI. F. Pre-axial polydactyly is noted (arrow). PDA = patent ductus arteriosus, VACTERL = vertebral, anorectal, cardiac, tracheoesophageal, renal, alimentary and limb defects

Fig. 18. A male neonate with Currarino syndrome.

A. Sacral deformity (arrow) is noted with a distended sigmoid colon (dot arrow). B. A solid and cystic presacral mass with intralesional fat suggests presacral teratoma (arrow). C. Rectal stenosis (arrow) is also noted on colon study.

Fig. 19. Variable simple radiographic findings of necrotizing enterocolitis.

A. Palisading patterned bowel distention is noted with pneumatosis intestinalis, which shows a lucent lining along the bowel wall. B. No significant interval changes of the bowel gas pattern since a previous study (A) suggests fixed bowel loops. C. A hypo-lucent line along the portal vein suggests portal vein gas (arrow). D. Development of a hypodense area above the liver is due to pneumoperitoneum. There is linear density above the hypodense area above the liver (arrow), which shows a shadow of the falciform ligament sandwiched between air. A relatively well delineable high density lining along the bowel wall in the left-sided abdomen suggests the double-wall sign (Rigler sign) (dot arrow). E. A cross table lateral view is useful to detect mild pneumoperitoneum (arrow).

Fig. 20. Variable ultrasonographic findings of necrotizing enterocolitis.

A. Diffuse bowel wall thickening with hyperemia can be noted. B. Pneumatosis intestinalis is noted with an echogenic air bubble (arrows) within the mural layer. C. Portal vein gas shows a linear echogenic lining along the portal vein branch. If Color doppler study is performed at the portal vein tract, there are multiple artifacts resulting from the passing air bubble when portal vein gas is present. D. Dirty ascites with debris (arrow) can be noted.