title: Delay before the hepatocyte phase of Gd-EOB-DTPA-enhanced MR imaging: is it possible to shorten the examination time?
abstract: OBJECTIVE
  To examine if it is possible to shorten the examination time of gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB)-enhanced MRI by omitting hepatocyte-phase images of 20-min delay time (Im-20) for detecting focal liver lesions.
  
  
  METHODS
  Four hundred ninety-five malignant focal liver lesions observed on Im-20 in 265 patients were included. The hepatocyte phase was obtained 10 min (Im-10) and 20 min (Im-20) after Gd-EOB injection. Liver enhancement was evaluated using a 4-point scale [excellent/good/poor/non-diagnostic; visual liver-spleen contrast (V-LSC)] and a quantitative liver-spleen contrast ratio (Q-LSC). Two radiologists evaluated lesion conspicuity for assessing the sensitivity of lesion detection. As Im-20 was used as the standard of reference for the lesions, Im-20 artificially had 100% sensitivity.
  
  
  RESULTS
  The results showed that although sensitivities and Q-LSC significantly increased from Im-10 to Im-20 (sensitivity/mean Q-LSC: Im-5, 81%/1.4 Im-10, 96%/1.7: Im-20, 100%/1.9), the sensitivity of Im-10 achieved 100% (the same as Im-20) in patients with good/excellent V-LSC or Q-LSC of more than 1.5. On Im-10, 202 patients (77%) were assigned as having good/excellent V-LSC (78%), and 161 (61%) were assigned as having Q-LSC of more than 1.5.
  
  
  CONCLUSIONS
  We concluded that Im-20 can be omitted in at least 61% of the patients.
authors.affiliation: Department of Radiology, University of Yamanashi, 1110 Shimokato, Chuo-shi, Yamanashi-ken 409-3898, Japan. utaroh-motosugi@nifty.com
authors.forename: Utaroh
authors.initials: U
authors.lastname: Motosugi
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Ichikawa
authors.forename: Licht
authors.initials: L
authors.lastname: Tominaga
authors.forename: Hironobu
authors.initials: H
authors.lastname: Sou
authors.forename: Katsuhiro
authors.initials: K
authors.lastname: Sano
authors.forename: Shintaro
authors.initials: S
authors.lastname: Ichikawa
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Araki
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media / Q000494:pharmacology*; D005260:Female; D019786:Gadolinium DTPA / Q000494:pharmacology*; D022781:Hepatocytes / Q000000981:diagnostic imaging* / Q000473:pathology*; D006801:Humans; D008099:Liver / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011877:Radionuclide Imaging; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013997:Time Factors
chemical_list: D003287:Contrast Media; C073590:gadolinium ethoxybenzyl DTPA; D019786:Gadolinium DTPA