[Ultrasound diagnosis of branchiogenic neck cysts]

16 operatively and histologically proven branchiogenic cysts were evaluated sonographically and the contents of some of them were analysed by microscopy and chemistry. The echographic appearance of all cysts depended on the frequency of the scanheads and ranged from cystic (3.0 MHz) via semi-solid (5.0 MHz) to solid (7.5 MHz). This frequency-related sonographic pattern is caused by the high amount of cholesterin contained in these cysts and permits diagnosis of a branchiogenic cyst.