title: Diagnosis of breast cancer with multidetector computed tomography: analysis of optimal delay time after contrast media injection.
abstract: OBJECTIVE
  The aim of this study was to investigate the optimal delay time after a contrast media injection for multidetector computed tomography (MD-CT) images in the diagnosis of breast cancer patients.
  
  
  METHODS
  Thirty-one patients who underwent MD-CT for their preoperative examination and who had postoperatively confirmed pathology were enrolled. Four-phase images of dynamic contrast enhanced study were acquired using four-detector MDCT. All cases were mammographically classified into two groups according to BI-RADS: nondense and dense groups. The CT value of the background mammary gland, background breast enhancement (BBE), and tumor-background mammary gland contrast (TBC) were compared between the two groups.
  
  
  RESULTS
  The CT value of the dense group was significantly higher than that of the nondense group in all phases. BBE in both nondense and dense groups showed no significant differences in any of the phases. In the nondense group, TBC was significantly higher in both the second and the third phases than in the first phase, while in the dense group, TBC was significantly higher in the second phase than in the first and third phases.
  
  
  CONCLUSIONS
  The optimal delay time to depict breast cancer is 80 s after a contrast media injection, regardless of the density level of the background mammary gland.
authors.affiliation: Research Center for Cancer Prevention and Screening, National Cancer Center, Tokyo 104-0045, Japan. skuroki@ncc.go.jp
authors.forename: Seiko
authors.initials: S
authors.lastname: Kuroki-Suzuki
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Kuroki
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Ishikawa
authors.forename: Hideya
authors.initials: H
authors.lastname: Takeo
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Moriyama
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000000981:diagnostic imaging*; D003287:Contrast Media / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D007275:Injections, Intravenous; D007455:Iodine / Q000008:administration & dosage*; D008327:Mammography / Q000379:methods*; D008875:Middle Aged; D011856:Radiographic Image Enhancement / Q000379:methods; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; D007455:Iodine