[Diagnostic sonography of the female breast].

The female breast can be easily examined by sonography due to its anatomical site. Today water-coupling methods or real-time scanners with high transducer frequency are the procedures of choice. The sonographic picture of the normal breast is described and a discussion presented of the criteria on which the differential diagnosis between cystic and solid lesions is based. The domain of sonography is the demonstration of cystic lesions as from a diameter of 3 mm. Solid lesions must be bigger to become demonstrable by sonography. Sonography is at present incapable of replacing mammography as a screening method for the early detection of breast cancer for several reasons. Primarily one has to spend at least half an hour for an exact examination of both breasts. A more serious disadvantage, however, is the fact that the majority of breast cancers demonstrated by sonography is far beyond the early stages. It was, moreover, observed that the sonographic appearance of the tumour was dependent on the cellular content of the tumour as well as the connective tissue density. Tumours with a high cellular content are more easily penetrable by ultrasonic waves and might, therefore, be misinterpreted as being a benign lesion. On comparing mammography and sonography it is interesting to note that tumours in a dense breast are more easily detectable by sonography, whilst tumours in a breast rich in fatty tissue are more easily demonstrated by mammography.