title: Preliminary study on the diagnostic value of acoustic radiation force impulse technology for differentiating between benign and malignant thyroid nodules.
abstract: OBJECTIVE
  This study aimed to evaluate the diagnostic value of acoustic radiation force impulse (ARFI) elasticity imaging for differentiating between benign and malignant thyroid lesions.
  
  
  METHODS
  Hospitalized patients needing thyroid surgery were evaluated. After routine thyroid sonography, the patients underwent ARFI elasticity imaging. Virtual Touch tissue imaging (VTI) and Virtual Touch tissue quantification (VTQ; Siemens Medical Solutions, Mountain View, CA) were used to qualitatively and quantitatively analyze the elasticity and hardness of nodules. For statistical analysis, the Student t test, analysis of variance, and the χ(2) test were used to compare the elastic parameters.
  
  
  RESULTS
  Of the 98 thyroid nodules observed in 72 hospitalized patients, 56 were nodular goiters, 16 thyroid adenomas, 4 thyroiditis, and 22 thyroid malignancies, with mean VTQ values ± SD of 2.034 ± 0.484, 1.835 ± 0.364, 2.293 ± 0.787, and 3.941 ± 1.393 m/s, respectively. The elastic parameters of malignant nodules were significantly higher than those of benign nodules (P < .001) and the surrounding thyroid parenchyma (P < .001). There was no significant difference between the VTQ value of benign nodules and that of the surrounding normal thyroid parenchyma (P > .05). For differentiating between benign and malignant nodules, the sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accordance rate were 86.36%, 93.42%, 79.17%, 95.95%, and 91.84% based on the standard VTQ value (2.555m/s). In total, 77.6% (59 of 76) of the benign nodules showed softer and equal images in the VTI mode, and 77.3% (17 of 22) of the malignant nodules showed stiffer images (P < .001).
  
  
  CONCLUSIONS
  Acoustic radiation force impulse imaging has high sensitivity and specificity in evaluating benign and malignant thyroid nodules and therefore had good diagnostic value in clinical applications.
authors.affiliation: Department of Ultrasound, Shanghai First People's Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China.
authors.forename: Jiying
authors.initials: J
authors.lastname: Gu
authors.forename: Lianfang
authors.initials: L
authors.lastname: Du
authors.forename: Min
authors.initials: M
authors.lastname: Bai
authors.forename: Huili
authors.initials: H
authors.lastname: Chen
authors.forename: Xiao
authors.initials: X
authors.lastname: Jia
authors.forename: Jing
authors.initials: J
authors.lastname: Zhao
authors.forename: Xuemei
authors.initials: X
authors.lastname: Zhang
mesh_terms: D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D016009:Chi-Square Distribution; D003937:Diagnosis, Differential; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric; D016606:Thyroid Nodule / Q000000981:diagnostic imaging* / Q000473:pathology