Lung ultrasound is a technique that has rapidly developed in recent
years. It is a low-cost, radiation-free, and easy-to-operate tool that
can be repeatedly performed at the bedside. Compared to chest X-ray,
lung ultrasound has high sensitivity and specificity in the diagnosis of
neonatal respiratory distress syndrome, transient tachypnoea of newborns
and pneumothorax. Lung ultrasound has been widely used in neonatal
intensive care units. However, it has limitations in some other lung
diseases and cannot fully substitute for chest X-ray or CT. This review
describes these limitations in detail and highlights that if clinical
symptoms are not effectively alleviated after medical treatment or the
clinical presentation is not compatible with the ultrasound appearances,
then chest X-ray or CT scanning should be performed to avoid
misdiagnosis and mistreatment.