title: Double inversion recovery MR imaging of the breast: efficacy in detection of breast cancer.
abstract: OBJECTIVE
  To investigate the efficacy of the double inversion recovery sequence (DIR) in breast cancer detection.
  
  
  METHODS
  Fifty-six patients with biopsy-proven breast cancers underwent preoperative breast MRI, including sagittal DIR and contrast-enhanced T1-weighted images (CE-T1WI). Twenty-four of the 56 patients additionally underwent sagittal T1WI and T2WI. The signal intensities of the lesion (L) and ipsilateral normal breast tissue (N) were measured. The lesion-to-normal ratio (LNR) was defined as LNR = 100(L-N)/N. We compared LNRs among the four sequences, and then assessed the differences of LNRs between CE-T1WI and DIR in each pathologic subgroup (IDC and non-IDC group). Multiple regression analysis was performed to identify predictors of the signal-to-noise ratios (SNR) of the normal tissue or lesion and LNRs.
  
  
  RESULTS
  The mean LNR did not differ significantly between DIR (58.65 ± 71.55) and CE-T1WI (59.78 ±31.04), nor did the LNRs between DIR and CE-T1WI in the two subgroups. The LNRs of DIR did not differ significantly between the two subgroups (P = 0.247). The SNR of lesions in DIR was correlated with the intraductal component percentage (r(2) = 0.485, P = 0.037).
  
  
  CONCLUSIONS
  DIR and CE-T1WI showed similar tumor detection efficacy, and DIR could complement dynamic MRI for detecting breast cancer without a contrast agent.
authors.affiliation: Department of Radiology, Kyung Hee University Hospital at Gangdong, College of Medicine, Kyung Hee University, 149 Sangil-dong, Gangdong-gu, Seoul, Republic of Korea.
authors.forename: Jeoung Hyun
authors.initials: JH
authors.lastname: Kim
authors.forename: Jung Kyu
authors.initials: JK
authors.lastname: Ryu
authors.forename: Geon-Ho
authors.initials: GH
authors.lastname: Jahng
authors.forename: Jeong Yoon
authors.initials: JY
authors.lastname: Song
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D001940:Breast / Q000473:pathology*; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000473:pathology; D003287:Contrast Media / Q000737:chemistry; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D012044:Regression Analysis; D015203:Reproducibility of Results; D012189:Retrospective Studies; D059629:Signal-To-Noise Ratio
chemical_list: D003287:Contrast Media
keywords: breast cancer; double inversion recovery; intraductal component; magnetic resonance imaging; tumor detection