Imaging description

A 36-week gestational age male presented clinically with failure to pass meconium at birth. Radiographs of the abdomen demonstrated abdominal distension and findings of mid to distal bowel obstruction (Fig. 56.1a). The clinical presentation was not unexpected since a prenatal ultrasound (US) performed at 19 weeks gestational age identified echogenic bowel, prompting further evaluation with a prenatal MRI at 27 weeks. The MRI findings of dilated bowel and a small rectum suggested the presence of distal bowel obstruction (Fig. 56.1b, c). A water-soluble contrast enema at two days of age (performed with Cysto-Conray II) demonstrated a microcolon containing multiple small filling defects/plugs (Fig. 56.1d). Contrast reached the cecum and appendix, located in the right upper quadrant. Contrast could not be refluxed into the terminal ileum. A decubitus view demonstrated many dilated small bowel loops without air–fluid levels, suggesting meconium ileus as the most likely diagnosis (Fig. 56.1e). However, ileal atresia, malrotation with small bowel volvulus, and total colonic Hirschsprung’s disease were also considerations. Surgical exploration at two days of age demonstrated severe meconium ileus extending into the mid small bowel causing marked jejunal dilatation secondary to the impacted meconium. Multiple plugs of inspissated meconium were removed surgically. However, postoperatively he continued to have bowel obstruction and inspissated bowel contents indicative of ongoing meconium ileus. He underwent a total of five water-soluble contrast enemas with a final successful enema, utilizing Gastrografin and Mucomyst, which relieved his obstruction (Fig. 56.1f).