title: Impact of nodular size on the predictive values of gray-scale, color-Doppler ultrasound, and sonoelastography for assessment of thyroid nodules.
abstract: OBJECTIVE
  To define the roles of gray-scale, color-Doppler ultrasound, and sonoelastography for the assessment of thyroid nodule to determine whether nodule size affects the differential diagnosis of benign and malignant.
  
  
  METHODS
  A total of 243 consecutive subjects (214 women, 29 men) with 329 thyroid nodules were examined by gray-scale, color-Doppler ultrasound, and sonoelastography in this prospective study. All patients underwent surgery and the final diagnosis was obtained from histopathological examination.
  
  
  RESULTS
  Three hundred and twenty-nine nodules (208 benign, 121 malignant) were divided into small (SNs, 5-10 mm, n=137) and large (LNs, >10 mm, n=192) nodules. Microcalcifications were more frequent in malignant LNs than in malignant SNs, but showed no significant difference between benign LNs and SNs. Poorly-circumscribed margins were not significantly different between malignant SNs and LNs, but were less frequent in benign LNs than in benign SNs. Among all nodules, marked intranodular vascularity was more frequent in LNs than in SNs. By comparison, shape ratio of anteroposterior to transverse dimensions (A/T) ≥ 1 was less frequent in LNs than in SNs. Otherwise, among all nodules, marked hypoechogenicity and elasticity score of 4-6 showed no significant difference between LNs and SNs.
  
  
  CONCLUSIONS
  The predictive values of microcalcifications, nodular margins, A/T ratio, and marked intranodular vascularity depend on nodule size, but the predictive values of echogenicity and elastography do not.
authors.affiliation: Department of Ultrasound, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009, China.
authors.forename: Yu-rong
authors.initials: YR
authors.lastname: Hong
authors.forename: Yu-lian
authors.initials: YL
authors.lastname: Wu
authors.forename: Zhi-yan
authors.initials: ZY
authors.lastname: Luo
authors.forename: Ning-bo
authors.initials: NB
authors.lastname: Wu
authors.forename: Xue-ming
authors.initials: XM
authors.lastname: Liu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002114:Calcinosis / Q000000981:diagnostic imaging; D002291:Carcinoma, Papillary / Q000000981:diagnostic imaging; D003937:Diagnosis, Differential; D054459:Elasticity Imaging Techniques; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D016606:Thyroid Nodule / Q000098:blood supply / Q000000981:diagnostic imaging* / Q000473:pathology; D013968:Thyroiditis, Subacute / Q000000981:diagnostic imaging; D018615:Ultrasonography, Doppler, Color; D055815:Young Adult