%0 Journal Article
%T Continuous Dynamic Registration of Microvascularization of Liver Tumors with Contrast-Enhanced Ultrasound
%A Lukas Philipp Beyer
%A Benedikt Pregler
%A Isabel Wiesinger
%A Christian Stroszczynski
%A Philipp Wiggermann
%A Ernst-Michael Jung
%J Radiology Research and Practice
%D 2014
%I Hindawi Publishing Corporation
%R 10.1155/2014/347416
%X Aim. To evaluate the diagnostic value of quantification of liver tumor microvascularization using contrast-enhanced ultrasound (CEUS) measured continuously from the arterial phase to the late phase (3 minutes). Material and Methods. We present a retrospective analysis of 20 patients with malignant ( ) or benign ( ) liver tumors. The tumors had histopathologically been proven or clearly identified using contrast-enhanced reference imaging with either 1.5ˋT MRI (liver specific contrast medium) or triphase CT and follow-up. CEUS was performed using a multifrequency transducer (1每5ˋMHz) and a bolus injection of 2.4ˋmL sulphur hexafluoride microbubbles. A retrospective perfusion analysis was performed to determine TTP (time-to-peak), RBV (regional blood volume), RBF (regional blood flow), and Peak. Results. Statistics revealed a significant difference ( ) between benign and malignant tumors in the RBV, RBF, and Peak but not in TTP ( ). Receiver operating curves (ROC) were generated for RBV, RBF, Peak, and TTP with estimated ROC areas of 0.97, 0.96, 0.98, and 0.76, respectively. Conclusion. RBV, RBF, and Peak continuously measured over a determined time period of 3 minutes could be of valuable support in differentiating malignant from benign liver tumors. 1. Introduction The radiomorphological differentiation between benign and malignant liver tumors with contrast-enhanced ultrasound is based on a continuous, dynamic evaluation of microvascularization of the tumor [1] and has been shown to be extremely reliable [2, 3]. Malignant liver tumors (HCC, CCC, and metastasis) often have an irregular, sometimes chaotic, early-arterial and arterial (15每45ˋsecs) microvascularization showing a hyperenhancement or rim enhancement [4] in the arterial phase and a hypoechogenic pattern in the portal-venous and the late (2每5ˋmins) venous phases [4每6]. Metastasis can be hypovascular (e.g., adenocarcinoma) with necrotic, nonenhanced areas or hypervascular (e.g., neuroendocrine tumors) with complete or partial hyperenhancement in the arterial phase. A common feature of almost all metastases is hypo- or nonenhancement in the portal and late phases [7每9]. Most benign hepatic lesions (haemangioma, focal nodular hyperplasia, and adenoma) show a rapid enhancement in the arterial phase with a prolonged enhancement in the late venous phase. They display mainly not only hyperechogenic but also isoechogenic patterns in the late phase [4每6]. Classical patterns include nodular, wheel-spike, or mixed accumulations as seen in haemangioma, focal nodular hyperplasia (FNH), and adenoma,
%U http://www.hindawi.com/journals/rrp/2014/347416/