title: Changes in signal-to-noise ratios and contrast-to-noise ratios of hypervascular hepatocellular carcinomas on ferucarbotran-enhanced dynamic MR imaging.
abstract: OBJECTIVE
  To verify changes in the signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) of hypervascular hepatocellular carcinomas (HCCs) on ferucarbotran-enhanced dynamic T1-weighted MR imaging.
  
  
  METHODS
  Fifty-two patients with 61 hypervascular HCCs underwent ferucarbotran-enhanced dynamic MR imaging, and then hepatic resection. Hypervascular HCCs were identified when definite enhancement was noted during the arterial dominant phase of three-phase MDCT. Dynamic MR Images with T1-weighted fast multiplanar spoiled gradient-recalled echo sequence (TR200/TE4.2) were obtained before and 20 s, and 1, 3, 5, and 10 min, after bolus injection of ferucarbotran. We estimated the signal intensities of tumors and livers, and calculated the SNRs and CNRs of the tumors.
  
  
  RESULTS
  On ferucarbotran-enhanced dynamic MR imaging, SNR measurements showed a fluctuating pattern, namely, an increase in SNR followed by a decrease and a subsequent increase (or a decrease in SNR followed by a increase and a subsequent decrease) in 50 (82.0%) of 61 tumors, a single-peak SNR pattern (highest SNR on 20 s, 1, 3, or 5 min delayed images followed by a decrease) in seven (11.5%), and a decrease in SNR followed by an increase in four (6.6%). Maximum absolute CNRs with positive value were noted on 10 min delayed images in 41 (67.2%) tumors, and maximum absolute CNRs with negative value were observed on 20 s delayed images in 12 (19.7%) and on 1 min delayed images in eight (13.1%).
  
  
  CONCLUSIONS
  Despite showing various SNR and CNR changes, the majority of hypervascular HCCs demonstrated a fluctuating SNR pattern on ferucarbotran-enhanced dynamic MR imaging and a highest CNR on 10 min delayed image, which differed from the classic enhancement pattern on multiphasic CT.
authors.affiliation: Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Kangnam-gu, Seoul 135-710, South Korea.
authors.forename: Yulri
authors.initials: Y
authors.lastname: Park
authors.forename: Dongil
authors.initials: D
authors.lastname: Choi
authors.forename: Seong Hyun
authors.initials: SH
authors.lastname: Kim
authors.forename: Seung Hoon
authors.initials: SH
authors.lastname: Kim
authors.forename: Min Ju
authors.initials: MJ
authors.lastname: Kim
authors.forename: Jongmee
authors.initials: J
authors.lastname: Lee
authors.forename: Jae Hoon
authors.initials: JH
authors.lastname: Lim
authors.forename: Won Jae
authors.initials: WJ
authors.lastname: Lee
authors.forename: Hyo K
authors.initials: HK
authors.lastname: Lim
mesh_terms: D000328:Adult; D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000473:pathology*; D003287:Contrast Media / Q000008:administration & dosage; D003911:Dextrans; D005260:Female; D052203:Ferrosoferric Oxide; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007275:Injections, Intravenous; D007501:Iron / Q000008:administration & dosage; D008113:Liver Neoplasms / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D058185:Magnetite Nanoparticles; D008297:Male; D008875:Middle Aged; D009389:Neovascularization, Pathologic / Q000473:pathology; D010087:Oxides / Q000008:administration & dosage
chemical_list: D003287:Contrast Media; D003911:Dextrans; D058185:Magnetite Nanoparticles; D010087:Oxides; D007501:Iron; C065507:ferumoxides; D052203:Ferrosoferric Oxide