title: In vivo thyroid vibro-acoustography: a pilot study.
abstract: BACKGROUND
  The purpose of this study was to evaluate the utility of a noninvasive ultrasound-based method, vibro-acoustography (VA), for thyroid imaging and determine the feasibility and challenges of VA in detecting nodules in thyroid.
  
  
  METHODS
  Our study included two parts. First, in an in vitro study, experiments were conducted on a number of excised thyroid specimens randomly taken from autopsy. Three types of images were acquired from most of the specimens: X-ray, B-mode ultrasound, and vibro-acoustography. The second and main part of the study includes results from performing VA and B-mode ultrasound imaging on 24 human subjects with thyroid nodules. The results were evaluated and compared qualitatively.
  
  
  RESULTS
  In vitro vibro-acoustography images displayed soft tissue structures, microcalcifications, cysts and nodules with high contrast and no speckle. In this group, all of US proven nodules and all of X-ray proven calcifications of thyroid tissues were detected by VA. In vivo results showed 100% of US proven calcifications and 91% of the US detected nodules were identified by VA, however, some artifacts were present in some cases.
  
  
  CONCLUSIONS
  In vitro and in vivo VA images show promising results for delineating the detailed structure of the thyroid, finding nodules and in particular calcifications with greater clarity compare to US. Our findings suggest that, with further development, VA may be a suitable imaging modality for clinical thyroid imaging.
authors.affiliation: Department of Physiology and Biomedical Engineering, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA. Alizad.azra@mayo.edu
authors.forename: Azra
authors.initials: A
authors.lastname: Alizad
authors.forename: Matthew W
authors.initials: MW
authors.lastname: Urban
authors.forename: John C
authors.initials: JC
authors.lastname: Morris
authors.forename: Carl C
authors.initials: CC
authors.lastname: Reading
authors.forename: Randall R
authors.initials: RR
authors.lastname: Kinnick
authors.forename: James F
authors.initials: JF
authors.lastname: Greenleaf
authors.forename: Mostafa
authors.initials: M
authors.lastname: Fatemi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013961:Thyroid Gland / Q000000981:diagnostic imaging*; D016606:Thyroid Nodule / Q000000981:diagnostic imaging*