To evaluate brain tissue disorders in infants, which test is useful?

• A. Computerized tomography.
• B. Ultrasonography.
• C. Head radiographs.
• D. Magnetic resonance imaging.

Answer: (B)

Evaluating brain tissue in infants is best done with ultrasonography through the open fontanelle. In early life, the fontanelles provide a window that lets ultrasound visualize the brain in real time at the bedside without radiation or sedation. This makes it especially useful for assessing ventricular size, hemorrhage, white‑matter injury, and major malformations in newborns and young infants. While CT can show hemorrhage and structural issues, it uses ionizing radiation and is less ideal for frequent or routine evaluation. MRI offers superior soft-tissue detail but often requires transport, longer scanning times, and sometimes sedation, making it less practical for initial or unstable cases. Head radiographs provide limited information about brain tissue and are not as helpful for detailed brain pathology.