title: Correlation between parametric imaging using contrast ultrasound and the histological differentiation of hepatocellular carcinoma.
abstract: OBJECTIVE
  To determine whether parametric imaging correlates with the degree of histological differentiation of hepatocellular carcinoma (HCC).
  
  
  METHODS
  The samples comprised 49 nodules diagnosed histologically as HCC: 19 well differentiated (w-HCC), 22 moderately differentiated (m-HCC), and eight poorly differentiated (p-HCC). The ultrasound (US) equipment used was SSA-770 A (Toshiba Medical Systems, Otawara, Japan) and the contrast agent was SonoVue (Bracco, Milan, Italy). After 1.5 mL of SonoVue was injected intravenously and staining of the tumors and parenchyma was confirmed, microbubbles in the scanned volume were eliminated using high mechanical index (MI) scanning frames. The "arrival time (T(A)) images," reflecting beta-values, were displayed with color codes at the phase after reperfusion. Images at the phase when the staining reached a plateau (90-180 s) were used as "A images," reflecting A values. These images were compared between each histological grade of differentiation.
  
  
  RESULTS
  Analysis of T(A) images indicated that beta-values in m-HCC were higher than those in the adjacent non-tumor parenchyma in all 22 samples and also were significantly higher than in the other HCCs (P < 0.001 for w-HCC; P < 0.05 for p-HCC). Furthermore, beta-values in p-HCC samples had significantly larger variations in terms of time and space than in the other HCCs (P < 0.001 for w-HCC; P < 0.01 for m-HCC). Analysis of A images indicated that the A value for w-HCC was significantly higher than those for either m-HCC or p-HCC (P < 0.001).
  
  
  CONCLUSIONS
  Both T(A) and A images were useful for diagnosing the histological differentiation of HCC.
authors.affiliation: Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan.
authors.forename: Katsutoshi
authors.initials: K
authors.lastname: Sugimoto
authors.forename: Fuminori
authors.initials: F
authors.lastname: Moriyasu
authors.forename: Naohisa
authors.initials: N
authors.lastname: Kamiyama
authors.forename: Masahiko
authors.initials: M
authors.lastname: Yamada
authors.forename: Hiroko
authors.initials: H
authors.lastname: Iijima