Research Information System
Japanese Journal of Radiology, vol.31, no.11, pp.750-754, 2013 (SCI-Expanded)
Purpose: The aim of this study is to evaluate the elasticity index of thyroid nodules by sonoelastographic imaging, and to determine the cut-off value to distinguish malignant nodules from benign nodules with optimum sensitivity and specificity. Materials and methods: Fine needle aspiration biopsy (FNAB) of 84 cases were evaluated with B-mode US and Sonoelastography (USE) preoperatively. The elasticity score (ELX 2/1) index of the nodules were calculated. Seventy-three patients with diagnostic biopsy results were included in this study. Results: According to the FNAB results, 9 (12 %) nodules were malignant, 64 (88 %) nodules were benign. All malignant nodules were papillary carcinoma, and their diagnosis was confirmed with thyroidectomy. The ELX 2/1 index of all malignant nodules was higher than 1.65. The ELX 2/1 index of 45 (70.3 %) benign nodules was lower than 1.65 whereas the ELX 2/1 index of 19 (29.7 %) benign nodules was higher than 1.65. Using an ELX 2/1 index cut-off value of 1.65 led to a sensitivity of 100 % and a specificity of 71 % in detecting papillary thyroid carcinomas. Conclusions: Assessing the ELX 2/1 index as a screening test and deciding on FNAB accordingly, in addition to gray-scale ultrasound findings of the nodules, will be beneficial in order to prevent unnecessary biopsies. © 2013 Japan Radiological Society.