Plain radiographs of the abdomen remain the current standard method for evaluation of neonates suspected or known to have necrotizing enterocolitis. Despite this sonography does play an important role in this condition. It is well documented that sonography is more accurate in delineating free fluid and focal fluid collections in the abdomen than radiographs. Furthermore sonography may even be more accurate in
certain circumstances than radiographs in depicted very small amounts of free gas in the peritoneal cavity. Sonography is also more accurate than radiographs in depicting bowel wall thickness (thickening or thinning), intramural gas and portal venous gas. This is particularly important when the plain radiographs are nonspecific and clinicians
are uncertain whether to initiate therapy for necrotizing enterocolitis. Further work is required to better define the role of sonography in this condition and and to determine which neonates are likely to benefit from evaluation with sonography.