[Comparative studies of various echomammography techniques].

Until now it is not clear which echographic scanning technique is most effective and economic for breast examination. To answer this question we examined in a special study 189 patients with the following scanning units: 1. automated immersion scanning technique, 3 MHz (Octoson, Ausonics) 2. manual compound scanning unit (skin contact), 5 MHz (80 LDI, Picker) 3. linear array realtime scanner (skin contact), 5 MHz (SAL 20, Toshiba). Two examiners evaluated the image quality with regard to the visualisation of the histologically confirmed malignant lesions (n = 78). For testing the spatial resolution, we developed a tissue--mimicking phantom including cyst-like structures of different sizes. The clinical and technical advantages and disadvantages respectively of these three methods are discussed.