High resolution contrast-enhanced ultrasound and 3-tesla dynamic contrast-enhanced magnetic resonance imaging for the preoperative characterization of cervical lymph nodes: First results.

The reliable detection of cervical lymph node (LN) metastases is the planning basis of a selective neck dissection for patients with oral squamous cell carcinoma (OSCC). The aim of this study was to evaluate whether contrast-enhanced ultrasound (CEUS) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) together are able to improve the preoperative characterisation of LNs. A time intensity curve analysis has been performed using CEUS and DCE-MRI for ten LNs, where one LN has been examined per patient. The studied LNs consist of five with and five without metastases. In CEUS the mean time to peak (TTP) was 18 s (range 13-29 s, standard deviation (SD) ± 7 s) for benign and 12 s (range 9-16 s, SD ± 4 s) for malignant LNs. In DCE-MRI the mean TTP was 27 s (range 18-36 s, SD ± 9 s) for benign and 21 s (range 18-27 s, SD ± 5 s) for malignant LNs. Moreover, the relative signal change with respect to reference tissue was significantly higher for LNs with than for those without metastases in both CEUS and DCE-MRI. A combination of imaging morphology, CEUS and DCE-MRI might be a promising method for a reliable differentiation of benign and malignant LNs.