[Reactive enlargement of cervical lymph nodes and cervical lymph node metastases: sonography (M/Q quotient) and computed tomography].

Ranking of sonographic maximum/transverse diameter quotients was compared with the ranking of CT in respect of identification and exclusion of cervical lymph node metastases. Both sonography and CT are distinguished by a high degree of sensitivity in the imaging of cervical lymph node metastases. Sonography, with the assistance of the maximum/transverse diameter quotient, can differentiate between benign enlarged and non-enlarged lymph nodes on the one hand and cervical lymph node metastases on the other, with a safety of 95 per cent. CT can yield definite information regarding the tumour status only after contrast medium administration under the criteria of central hypodensity and peripheral marginal enhancement. CT is much less specific than the sonographic M/T quotient (66% vs 95%). Accuracy of sonography (94%) is clearly superior to that of CT (79%).