Journal of Ultrasound in Medicine, Vol 18, Issue 7 445-451, Copyright © 1999 by American Institute of Ultrasound in Medicine
Echo-enhanced Doppler sonography of focal nodular hyperplasia of the liver
M. M. Uggowitzer, C. Kugler, H. J. Mischinger, R. Groll, A. Ruppert-Kohlmayr, K. W. Preidler and F. Quehenberger
Department of Radiology, University of Graz, Austria.
Lesions of focal nodular hyperplasia are hypervascular, benign focal liver
lesions whose differentiation from other focal liver lesions is of
significant clinical relevance. The purpose of this study was to
investigate the echo-enhancing agent SHU 508A (Levovist) in the evaluation
of focal nodular hyperplasia with Doppler sonography. We examined 49
patients with 71 lesions of focal nodular hyperplasia in the liver with
gray scale and power Doppler sonography. In all patients Levovist was
administered intravenously in a concentration of 300 to 400 mg galactose
per milliliter. Visualization of the feeding vessels and the vascularity of
the lesions were evaluated, and the resistive indices in the feeders and
the hepatic arteries were assessed. In comparison with unenhanced power
Doppler sonography, echo-enhanced power Doppler sonography yields a higher
sensitivity in the detection of the feeding artery (97% versus 82%) in
focal nodular hyperplasia and in the depiction of the radial vascular
architecture in such lesions, especially those located in the left lobe of
the liver. Lesions less than 3 cm in diameter do not consistently show a
characteristic vascular architecture with echo-enhanced Doppler sonography.
The resistive index of the tumor-feeding artery (mean, 0.51 +/- 0.09) is
significantly (P < 0.0001) lower than that of the hepatic artery (mean,
0.65 +/- 0.06) and decreases as the size of the focal nodular hyperplasia
increases. The administration of Levovist may improve the signal-to-noise
ratio and thus visualization of the vascular architecture in focal nodular
hyperplasia. Lesions located in the left lobe of the liver, which commonly
are subject to disturbing motion artifacts in color Doppler sonography,
will significantly benefit from the administration of Levovist.
Echo-enhanced power Doppler sonography, however, is not capable of
depicting a characteristic vascular pattern in small (< or = 3 cm)
lesions of focal nodular hyperplasia that would guarantee a specific
diagnosis.
