[Double images in B-mode sonography due to acoustic dispersion lenses].

Clinical observations revealed that duplication artifacts in B-mode-ultrasound depend on rib cartilage in the sound field. The in-vivo conditions were imitated by watertank experiments with an acrylic glass magnifier which has the properties of an acoustic dispersing lens. With this the duplication artifacts proved to be caused by acoustic dispersing lenses, in-vivo due to rib cartilage, for example.