Focal liver tumors: characterization with 3D perflubutane microbubble contrast agent-enhanced US versus 3D...

To investigate the potential application of contrast material-enhanced three-dimensional (3D) ultrasonography (US), as compared with contrast-enhanced 3D computed tomography (CT), for characterization of focal liver tumors.

Institutional review board approval and informed patient consent were obtained. One hundred thirty-nine patients with focal liver tumors-77 hepatocellular carcinomas (HCCs), 33 metastases, 23 hemangiomas, and six focal nodular hyperplasias (FNHs)-who were examined at 3D US enhanced with a perflubutane microbubble contrast agent and at 3D contrast-enhanced multidetector CT were retrospectively identified. Two readers blindly reviewed the multiplanar images and angiograms reconstructed with both modalities and classified the depicted lesions according to diagnostic criteria based on their experience and published findings. Sensitivity, specificity, positive predictive value (PPV), area under the receiver operating characteristic curve (A(z)), intermodality agreement, and interreader agreement were assessed.

Readers 1 and 2 had concordant US and CT findings for 115 (83%) and 116 (83%) of the 139 lesions, respectively, with moderate to excellent (kappa = 0.55-0.81) intermodality agreement. There were no significant differences between the two modalities: Sensitivity was 83% or greater with both modalities, specificity was 87% or greater with contrast-enhanced US and 92% or greater with contrast-enhanced CT, the PPV was 71% or greater with both modalities, and the A(z) was at least 0.89 with US and at least 0.92 with CT. Interreader agreement was good to excellent (kappa > or = 0.76) with both modalities.

Contrast-enhanced 3D US potentially can be used to characterize focal liver tumors.