Ultrasound, particularly cranial ultrasound (CUS), is performed by placing a transducer over the anterior fontanelle (the soft spot on a newborn's head). This allows real-time imaging of the brain. It is particularly useful for detecting: - Intraventricular Hemorrhage (IVH): Bleeding into the brain's ventricular system. - Periventricular Leukomalacia (PVL): White matter injury often seen in premature infants. - Hydrocephalus: Accumulation of cerebrospinal fluid in the brain.