Meconium in perinatal imaging: associations and clinical significance.

An abnormal location, distribution, volume, or appearance of meconium is associated with a spectrum of bowel abnormalities, including atresia, obstruction, perforation, fistula, aganglionosis, immaturity, and absorptive dysfunction. This review discusses the fetal and perinatal imaging of these entities, their differential diagnoses, clinical significance, and appropriate imaging workup. Understanding the spectrum of normal and abnormal, specific and nonspecific appearances of meconium and its associated abnormalities on imaging will provide a practical, useful framework for performing and interpreting imaging studies and guiding clinical management.