Background. It is crucial to differentiate between reactive and malignant lymphadenopathies. Elastosonography measures the elasticity of the tissue. Having a reference value for benign lymph nodes (LNs) is important in interpretation. The purpose of this study is to determine the reference elastosonography values of cervical LNs. Methods. 97 LNs were evaluated by B-mode and elastosonography. Depth, length, width, length to width ratio, hilar-cortical thickness, strain ratio, and elasticity scores were measured. Results. In 18.6% of the cervical LNs cortical thickness was less than the hilar thickness (group A) and in 81.4% it was equal or more (group B). 69.1% of LNs showed strain ratio (SR) less than 3 (group 1) and 30.9% equal to or more than 3 (group 2). 33% of LNs displayed elasticity score (ES) 1; 30.9% ES 2; 22.7% ES 3, and 13.4% ES 4. There was a significant correlation between thickness ratios and elasticity scores (P: 0.011). A significant correlation was also demonstrated between SR groups and elasticity scores. Conclusion. A simple, reproducible, noninvasive imaging technique for diagnosis of malignant LNs is necessary. Elastosonography can aid in the differentiation of benign versus malignant cervical LNs, thus help reduce the number of unnecessary biopsies for benign processes. 1. Introduction Elastosonography is an ultrasound based diagnosis which measures the elasticity or stiffness of the tissue. Compressibility of the tissue is a parameter evaluated by an elastogram and it is expressed as the change in tissue displacement as a function of its distance from the probe which is recognised as strain [1]. Among the 400–450 lymph nodes (LNs) of the human body, 60–70 are located in the head and neck area. LNs display reactive enlargement in infection and also when they are primarily or secondarily involved in malignancies of head and neck. Cervical LN metastasis may even be the first symptom in the malignant processes. It is crucial to differentiate between reactive and malignant lymphadenopathies. An important criterion is the hardness of the LN, because LNs might demonstrate increased stiffness on the elastogram if affected by a malignant process [2–4]. Having a reference value for benign LNs is important in interpretation. The purpose of this study is to determine the reference sonoelastography values of cervical LNs. 2. Materials and Methods 2.1. Patients After obtaining the approval of the ethical committee, patients referred to the radiology department for cervical vascular Doppler ultrasonography examination from January to March 2013
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