title: Maximal stiffness evaluation by real-time ultrasound elastography, an improved tool for the differential diagnosis of thyroid nodules.
abstract: OBJECTIVE
  The aim of the study was to evaluate the diagnostic performance of a new ultrasound elastography (USE) parameter based on the measurement of the percentage of maximal stiffness within a nodule as compared with the already established elastographic strain index (SI) and to investigate their diagnostic performance according to nodule size.
  
  
  METHODS
  The study included 218 nodules. Each nodule underwent conventional ultrasound (US), USE evaluation, and fine-needle aspiration cytology (FNAC). Thyroid nodules were further stratified into 4 subgroups (G) according to their size (G1, <1 cm; G2, 1-2 cm; G3, >3 cm). USE evaluation comprised the measurement of the percentage of the areas included in the region of interest corresponding to the maximal stiffness (% Index) and of the SI.
  
  
  RESULTS
  The % Index and of the SI were significantly higher in malignant than in benign thyroid nodules, and both measurements displayed a good diagnostic performance (SI sensitivity and specificity, 0.66 and 0.90, respectively; % Index sensitivity and specificity, 0.76 and 0.89, respectively). Compared with SI, the % Index was more informative, both in the whole group of thyroid nodules (odds ratio [OR], 18.68; 95% confidence interval [CI], 6.06 to 63.49; P<.0001 versus OR, 26.15; 95% CI, 8.01 to 102.87; P<.0001, respectively) and in the G1 and G2 subgroups.
  
  
  CONCLUSIONS
  The % Index is a stronger predictor of nodule malignancy than both the SI and the conventional US signs. This is particularly true in nodules smaller than 1 cm, which are more difficult to explore both by conventional US and FNAC.
authors: Flavia
authors: F
authors: Magri
authors: Spyridon
authors: S
authors: Chytiris
authors: Francesca
authors: F
authors: Zerbini
authors: Valentina
authors: V
authors: Capelli
authors: Margherita
authors: M
authors: Gaiti
authors: Andrea
authors: A
authors: Carbone
authors: Rodolfo
authors: R
authors: Fonte
authors: Alberto
authors: A
authors: Malovini
authors: Mario
authors: M
authors: Rotondi
authors: Riccardo
authors: R
authors: Bellazzi
authors: Luca
authors: L
authors: Chiovato
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D044963:Biopsy, Fine-Needle; D003937:Diagnosis, Differential; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D012680:Sensitivity and Specificity; D016606:Thyroid Nodule / Q000000981:diagnostic imaging* / Q000473:pathology; D014463:Ultrasonography / Q000379:methods*