title: Detection and characterization of focal hepatic tumors: a comparison of T2-weighted MR images before and after the administration of gadoxectic acid.
abstract: OBJECTIVE
  To evaluate if T2-weighted images (T2WI) after administration of gadoxetic acid have diagnostic capability comparable to precontrast T2WI in the detection and characterization of focal liver lesions.
  
  
  METHODS
  Eighty patients with 128 liver lesions (71 hepatocellular carcinomas, 35 metastases, and 22 hemangiomas) underwent gadoxetic acid-enhanced T1WI and precontrast and postcontrast turbo spin echo-short tau inversion recovery (TSE-STIR) and respiratory triggered (RT)-TSE. The sensitivity for malignancy with combining T2WIs and enhanced T1WIs was evaluated and percentage of signal intensity loss (PSIL) and lesion-liver contrast to noise ratio (CNR) were calculated for T2WIs. Lesion characterization with T2WIs as solid and nonsolid was evaluated using kappa statistics.
  
  
  RESULTS
  The PSIL was higher with TSE-STIR than with RT-TSE (P = 0.0001). The malignancy-liver CNRs on postcontrast T2WIs were higher than on precontrast T2WIs (P = 0.0001). Sensitivity for malignancy by combining postcontrast T2WIs and T1WIs (93.0% [hepatocellular carcinoma, HCC]; 97.1% [metastases]) was comparable to sensitivity of combining precontrast T2WIs and postcontrast T1WIs (91.6% [HCC]; 88.6% [metastases]). Kappa values for T2WIs indicated excellent agreement (k = 0.935).
  
  
  CONCLUSIONS
  Gadoxetic acid-enhanced T2WIs showed a comparable diagnostic capability to precontrast T2WIs for the detection and characterization of hepatic tumors.
authors.affiliation: Department of Diagnostic Radiology, Chonbuk National University Medical School and Hospital, Jeonbuk, South Korea. jmyr@dreamwiz.com
authors.forename: Young Kon
authors.initials: YK
authors.lastname: Kim
authors.forename: Hyo Sung
authors.initials: HS
authors.lastname: Kwak
authors.forename: Chong Soo
authors.initials: CS
authors.lastname: Kim
authors.forename: Young Min
authors.initials: YM
authors.lastname: Han
mesh_terms: D000328:Adult; D000368:Aged; D003287:Contrast Media / Q000008:administration & dosage*; D005260:Female; D019786:Gadolinium DTPA / Q000008:administration & dosage*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media; C073590:gadolinium ethoxybenzyl DTPA; D019786:Gadolinium DTPA