title: Contrast-enhanced ultrasonography findings using a perflubutane-based contrast agent in patients with early hepatocellular carcinoma.
abstract: OBJECTIVE
  We evaluated the contrast-enhanced ultrasonography (US) imaging features of early hepatocellular carcinomas (HCCs) and compared these findings with those obtained using contrast-enhanced computed tomography (CT).
  
  
  METHODS
  Forty-three patients with 52 early HCCs with a mean maximal diameter of 15.6mm were enrolled in this retrospective study. After confirming the location of the target lesion using fusion imaging combining conventional US and hepatobiliary phase of contrast-enhanced magnetic resonance (MR) imaging with gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid, we evaluated findings of contrast-enhanced US using a perflubutane-based contrast agent. The contrast-enhanced US detection rates for hyper-vascularity in early HCCs were compared with those obtained for contrast-enhanced CT.
  
  
  RESULTS
  Transient hypo-vascularity subsequent to iso-vascularity during arterial phase and iso-vascularity during portal and post-vascular phases were the predominant contrast-enhanced US findings seen for 25 (48.1%) of the 52 early HCCs. Nine (17.3%) showed iso-vascularity during all three phases, while 1 (1.9%) showed hypo-vascularity during all three phases. The remaining 17 (32.7%) showed partial or whole hyper-vascularity during arterial phase, iso-vascularity during portal phase, and iso- or hypo-vascularity during post-vascular phase. The detection rate for the hyper-vascularity of early HCCs using contrast-enhanced US (32.7%, 17/52) was significantly higher than that obtained using contrast-enhanced CT (21.2%, 11/52) (P<0.05 by McNemar test).
  
  
  CONCLUSIONS
  Hypo-vascularity, iso-vascularity, and hyper-vascularity were observed during the arterial phase of contrast-enhanced US in 50.0%, 17.3%, and 32.7% of the early HCCs, respectively. Contrast-enhanced US was more sensitive than contrast-enhanced CT for the detection of hyper-vascularity in early HCCs. Of note, early HCCs might not exhibit the early arterial enhancement that is generally considered to be a typical finding for HCCs.
authors.affiliation: Gastroenterological Center, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, Kanagawa 232-0024, Japan. Electronic address: kz-numa@urahp.yokohama-cu.ac.jp.
authors.forename: Kazushi
authors.initials: K
authors.lastname: Numata
authors.affiliation: Gastroenterological Center, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, Kanagawa 232-0024, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Fukuda
authors.affiliation: Gastroenterological Center, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, Kanagawa 232-0024, Japan.
authors.forename: Haruo
authors.initials: H
authors.lastname: Miwa
authors.affiliation: Gastroenterological Center, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, Kanagawa 232-0024, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Ishii
authors.affiliation: Gastroenterological Center, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, Kanagawa 232-0024, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Moriya
authors.affiliation: Gastroenterological Center, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, Kanagawa 232-0024, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Kondo
authors.affiliation: Gastroenterological Center, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, Kanagawa 232-0024, Japan.
authors.forename: Akito
authors.initials: A
authors.lastname: Nozaki
authors.affiliation: Gastroenterological Center, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, Kanagawa 232-0024, Japan.
authors.forename: Manabu
authors.initials: M
authors.lastname: Morimoto
authors.affiliation: Department of Radiology, Kinki University Faculty of Medicine, 377-2 Ohno-Higashi, Osaka-Sayama, Osaka 589-8511, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Okada
authors.affiliation: Department of Radiology, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, Kanagawa 232-0024, Japan.
authors.forename: Shigeo
authors.initials: S
authors.lastname: Takebayashi
authors.affiliation: Division of Gastroenterology, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, Kanagawa 236-0004, Japan.
authors.forename: Shin
authors.initials: S
authors.lastname: Maeda
authors.affiliation: Department of Pathology, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, Kanagawa 232-0024, Japan.
authors.forename: Akinori
authors.initials: A
authors.lastname: Nozawa
authors.affiliation: Pathological Department, Ofuna Chuo Hospital, 6-2-24 Ofuna, Ofuna, Kanagawa 247-0055, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Nakano
authors.affiliation: Gastroenterological Center, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, Kanagawa 232-0024, Japan.
authors.forename: Katsuaki
authors.initials: K
authors.lastname: Tanaka
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D006528:Carcinoma, Hepatocellular / Q000175:diagnosis*; D003287:Contrast Media; D055088:Early Detection of Cancer / Q000379:methods*; D005260:Female; D005290:Ferric Compounds; D019786:Gadolinium DTPA; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007501:Iron; D008113:Liver Neoplasms / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods; D009389:Neovascularization, Pathologic / Q000175:diagnosis*; D010087:Oxides; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014463:Ultrasonography / Q000379:methods*
chemical_list: D003287:Contrast Media; D005290:Ferric Compounds; D010087:Oxides; C069727:Sonazoid; C073590:gadolinium ethoxybenzyl DTPA; D007501:Iron; D019786:Gadolinium DTPA
keywords: Contrast-enhanced CT; Contrast-enhanced ultrasonography; Early hepatocellular carcinoma; Vascularity