ABSTRACT
Objective To evaluate the clinical value of elasticity imaging and area ratio by ultrasonography in differential diagnosis of benign and malignant thyroid nodules.Methods Gray-scale ultrasound and elasticity imaging was used to examine 88 patients with thyroid nodules.The elasticity classification and area ratio were retrospectively reviewed and compared with pathology.The elasticity grades 1 - 3 predicted benign,grades 4 - 5 predicted malignant.Results Eighty-eight patients with 116 thyroid nodules were detected,93 nodules were benign and 23 nodules were malignant.( 1 )An elasticity grades of 1 - 3 was observed in 82 (95.3％) of 86 benign nodules,while elasticity grades of 4 - 5 in 19 (63.3％) of 30 malignant nodules.The diagnosis sensitivity,specificity and accurate rate of the elasticity grades was 82.6％,88.2％,87.1％.(2) The mean of elasticity imaging and area ratio of 93 benign nodules (1.31 ± 0.13 ) was statistically lower than that in 23 malignant nodules ( 1.73 ± 0.13 ) (t =13.536,P =0.001 ).( 3 )According to ROC analysis,the cut-off point of elasticity imaging and area ratio was determined as 1.52.With elasticity imaging and area ratio ＜ 1.52,89 nodules [98.9％(89/90)] were confirmed as benign and 22 nodules [84.6％ (22/26)] were confirmed as malignant by pathology.The diagnosis sensitivity,specificity and accurate rate of elasticity imaging and area ratio was 95.7％,95.7％,95.7％.(4)The area under the ROC curve of elasticity imaging and area ratio ≥ 1.52 was 0.996,significantly higher than that of elasticity grades ≥ 4 (0.891).The diagnostic accurate rate of elasticity imaging and area ratio was significantly higher than that of elasticity grades(95.7％ vs.87.1％,x2 =5.472,P=0.019).Conclusions The elasticity imaging and area ratio by ultrasonography can be used in the differential diagnosis of thyroid lesions.It is a new diagnostic indicator for diagnosis of thyroid lesions.