坏死性小肠结肠炎（necrotizing enterocolitis, NEC）是新生儿常见胃肠道危重症，重症患儿预后不良甚至死亡，早期精准诊断对改善预后至关重要。传统腹部X线检查敏感性低，腹部超声作为无创、无辐射的实时成像技术，可早期评估肠壁结构、蠕动及灌注状态，对该病早期诊断具有突出价值。其典型超声表现包括肠壁增厚或变薄、血流灌注异常、肠壁积气、门静脉积气、气腹及复杂性腹水等。超声对这些征象的判断效能优于X线，尤其适用于X线结果不明确或需动态监测的病例，可作为NEC首选影像学检查方法之一。

Necrotizing enterocolitis (NEC) is a common critical gastrointestinal disease in neonates. Severe cases have a poor prognosis and may be fatal. Early and accurate diagnosis is crucial for improving outcomes. Traditional abdominal X-ray has low sensitivity. As a noninvasive, radiation-free real-time imaging technique, abdominal ultrasound can assess intestinal wall structure, peristalsis, and perfusion at an early stage and has outstanding value for early diagnosis. Typical ultrasound findings include intestinal wall thickening or thinning, abnormal blood perfusion, pneumatosis intestinalis, portal venous gas, pneumoperitoneum, and complex ascites. Ultrasound outperforms X-ray in identifying these signs, and it is particularly useful when X-ray findings are inconclusive or when dynamic monitoring is required. It can be considered one of the preferred imaging modalities for NEC.