Contrast-enhanced sonography in the examination of benign and malignant adnexal masses

Our objective was to characterize the properties of an intravascular ultrasonographic contrast agent in examination of adnexal masses and to compare contrast agent properties between benign and malignant adnexal tumors. Fifty-eight consecutively examined women with suspected ovarian tumors were examined preoperatively by power Doppler ultrasonography, first without and then with contrast agent enhancement (Levovist). Fourteen women had ovarian cancer, 3 had borderline ovarian tumors, 18 had benign ovarian neoplasms, and 23 had functional adnexal cystic masses or endometriomas. The effect of the contrast agent was evaluated visually and by using computerized power Doppler signal intensity measurements. In visual evaluation, the brightness of the power Doppler signal and the amount of recognizable vascular areas increased in each tumor after contrast agent administration. The number of vessels in power Doppler ultrasonograms, both before and after contrast agent enhancement, was significantly higher in malignant than in benign adnexal masses, as also was the increase in the number of recognizable vessels after contrast agent administration. Contrast agent uptake time was significantly shorter in malignant than in benign tumors. No significant differences were found in the power Doppler signal intensities or their changes between benign and malignant tumors. In conclusion, use of sonographic contrast agent facilitates imaging of tumor vessels. For differentiation of benign and malignant tumors, the kinetic properties of the contrast agent, such as uptake and washout times, may have more potential than the use of the contrast agent in anatomic imaging of the tumor vessels.