Detection of intratumoral vascularity in small hepatocellular carcinoma by coded phase inversion harmonics.

OBJECTIVE: To investigate the value of contrast-enhanced coded phase inversion harmonic imaging (PIHI) in the depiction of intratumoral vascularity in small hepatocellular carcinoma (HCC).

METHODS: Eighty-five patients with 106 HCCs < or =3 cm in diameter were evaluated with coded harmonic angio (CHA), a coded PIHI, with use of an intravenous contrast medium, Levovist. Intratumoral vessels were detected in the early arterial phase, and tumor parenchymal stain was demonstrated in the late vascular phase. The detectability of intratumoral vascularity on contrast-enhanced CHA was compared with that on dynamic computed tomography (CT) and digital subtraction angiography (DSA).

RESULTS: With a combination of both vessel images and parenchymal flow images demonstrated by contrast-enhanced CHA, 98 of 106 small HCCs were evaluated as being hypervascular or isovascular. Using the results on dynamic CT as a gold standard, the sensitivity, specificity and accuracy were 95.1, 100 and 95.3%, respectively. The detection rate of intratumoral vascularity by contrast-enhanced CHA was 92.5% (98/ 106), compared with 97.2% (103/106) on dynamic CT (p = 0.14) and 88.9% (40/45) on DSA (p = 0.53).

CONCLUSIONS: Contrast-enhanced coded PIHI is a sensitive tool for depicting intratumoral vascularity of small HCC.