A case of branchial (lympho-epithelial) cyst, illustrating the value of ultrasound in diagnosis of cervical swellings.

Ultrasound has until recently found little application in oral and maxillofacial surgery despite wide use in other specialties. Ultrasound imaging uses the reflection of pulses of high frequency sound to display soft tissues and to differentiate between tissue types, particularly solid and cystic. A case of branchial (lymphoepithelial) cyst is presented to illustrate the use of ultrasound, and the aetiology and histogenesis of this controversial lesion is discussed. Ultrasound as a safe, painless, non-invasive technique is recommended as an additional investigation for neck swellings, particularly in view of the high incidence of malignancy claimed to occur in this region.