Our aim was to evaluate the effectiveness of Levovist SHU 508 A (Shering, Germany) in the characterization of breast lesions. From June 1996 to May 1997 we studied 29 solid lesions in 29 patients (28 women and one man) between the age of 17 and 83 years. The 29 solid lesions included of 20 carcinomas (15 DCI ductal invasive carcinoma, 4 DCIS ductal carcinoma in situ, 1 LCIS lobular carcinoma in situ) 6 fibroadenomas, 1 postsurgical lesion and 2 apparently benign lesions at mammography, suspected after contrast agent injection, with histologically proven malignancy. We used parameters suitable for the study of low flow. A single bolus of contrast, at a concentration of 300 mg/ml, was administrated at a rate of 1-2 ml/sec. Morphological parameters, considered, before the administration of the Levovist were signal intensity and number of vascular poles. After contrast we assessed the previous parameters and the following: the presence and modification of vessels, not seen at the previous ultrasound exam, the increased in the number of vessels the initial modification, the duration of enhancement, and the presence of vessels within and external to the lesion. Considering the signal intensity after contrast there was no improvement in 17 % of cases, mild increases in 7 % and marked improvement in 76 % of cases. We have obtained an increase in the number of vessels in 10 % of cases. The type of enhancement characteristic of carcinoma (rapid increase, marked intensity) and fibroadenoma (slow increase with a lower intensity) were observed. This study demonstrated that Levovist can be useful in the following cases: differential diagnosis of benign from malignant lesions, differentiation between recurrence and post-surgical fibrosis, staging and follow-up of patients treated with chemotherapy