title: Correlation of CT values, iodine concentration, and histological changes in the thyroid.
abstract: OBJECTIVE
  We have reported that in the thyroid, there is a linear correlation between iodine concentrations and CT values. However, the slope of the regression line was about three times as large as that in KI solutions. We investigated the factor(s) contributing to the increment of the slope of the regression line in the thyroid.
  
  
  METHODS
  Solutions of NH4I and thyroid hormones were used to investigate the regression line. Thirty-six thyroids were evaluated to investigate the correlation between the iodine concentrations and the area ratio of thyroid follicles, which were measured by preoperative CT and from tissue slices, respectively.
  
  
  RESULTS
  The slopes of the regression lines in the solutions were almost identical to those in KI solutions. In the thyroid, iodine concentrations were logarithmically correlated with the area ratio of follicles.
  
  
  CONCLUSIONS
  The decrease in CT values not only revealed a decrease of iodine concentration in the thyroid but also represented an increase of follicular cells and/or interstitial structures in the volume ratio secondary to it.
authors.affiliation: Department of Radiology, St. Marianna University Yokohama Seibu Hospital, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Imanishi
authors.forename: N
authors.initials: N
authors.lastname: Ehara
authors.forename: T
authors.initials: T
authors.lastname: Shinagawa
authors.forename: D
authors.initials: D
authors.lastname: Tsujino
authors.forename: I
authors.initials: I
authors.lastname: Endoh
authors.forename: K
authors.initials: K
authors.lastname: Baba
authors.forename: Y
authors.initials: Y
authors.lastname: Kanemaki
authors.forename: S
authors.initials: S
authors.lastname: Iida
authors.forename: M
authors.initials: M
authors.lastname: Hayakawa
authors.forename: O
authors.initials: O
authors.lastname: Miyazaki
authors.forename: K
authors.initials: K
authors.lastname: Shirakawa
authors.forename: S
authors.initials: S
authors.lastname: Nosaka
mesh_terms: D006801:Humans; D007454:Iodides / Q000032:analysis; D007455:Iodine / Q000032:analysis* / Q000378:metabolism; D016014:Linear Models; D019047:Phantoms, Imaging; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D013959:Thyroid Diseases / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology; D013961:Thyroid Gland / Q000737:chemistry* / Q000000981:diagnostic imaging* / Q000473:pathology; D013974:Thyroxine / Q000032:analysis; D014057:Tomography, X-Ray Computed; D014284:Triiodothyronine / Q000032:analysis
chemical_list: D007454:Iodides; D014284:Triiodothyronine; D007455:Iodine; D013974:Thyroxine