Pearls and Pitfalls in Ultrasound of Pediatric Head and Neck

US is the first imaging method for several diseases of the head and neck in pediatric patients, including developmental and acquired lesions. To get the most benefit out of US examination, good technique in scanning and good knowledge in interpretation are required. Knowledge of developmental disorders (e.g., thyroglossal duct cyst, branchial cleft or pouch anomalies), unique pediatric normal structures (e.g., thymus, palatine tonsil) and the ones in ectopic location (e.g., thyroid, thymus, parotid), unique pediatric diseases (e.g., hemangioma, fibromatosis colli), awareness of a pseudo-solid or pseudo-cystic lesion and adding techniques to clarify (e.g., adjust settings, turn on color mode, compressing), knowing the artifacts (e.g., mirror image from skull), and getting the most out of clinical information (e.g., patient’s age, mass appears only in specific position or situation, sign of inflammation) are very important for scanning and interpretation. Many of the pitfalls are from not following the basic ultrasound scanning instructions. The examples of the basic instructions are selecting the appropriate type and frequency of the transducer, covering the appropriate depth, selecting proper window for scanning, scanning in two orthogonal planes, and comparing the echogenicity.