[Sonographic differential diagnosis of cervical masses].

One of the main indications for the use of ultrasound by the head and neck specialist is the diagnosis of cervical masses. The examination can be easily performed since all structures of interest are located superficially and are not covered by boney or air-filled structures. Further advantages of ultrasound in contrast to other imaging techniques such as MRI or CT include its high resolution and lack of side effects. Even structures of <5 mm in diameter can be interpreted well. Since ultrasound is fast, has no side effects and can be performed as often as necessary, it represents an excellent diagnostic instrument in the follow-up of patients with head and neck cancer. In addition to the conventional B-scan technique, colour duplex sonography is also often performed today to obtain additional information on the nature of cervical masses. Thus, different entities of cervical lymph nodes can be well differentiated by their pattern of vascularization. © Springer-Verlag 2010