Neonatal colonic atresia: ultrasound findings.

High resolution real-time ultrasound examination of the abdomen was performed in a neonate with abdominal distention. Dilated distal small bowel and a complex mass in the course of the ascending colon were noted. Ultrasound correctly suggested the diagnosis of mid-colonic atresia with a patent ascending colon twelve hours prior to the radiographic demonstration of gas in the obstructed right colon. The sonogram was also able to accurately exclude the presence of ascites or a renal or hepatic mass as the cause for abdominal distention.