[Ultrasonography of the breast].

Mammography, which is the first-choice examination for breast disease, has some limitations despite recent technical improvement, which has lead to better image quality and reduced x-ray exposure. It is less accurate in dense breasts, which are sometimes difficult to read and in which a palpable lesion or an infraclinical cancer is often not recognized. In such cases, ultrasonography is very useful and should be used as the second examination technique. Breast sonography done by a skilled sonographer with a good equipment can raise the accuracy for benign or malignant breast lesions.