[3D-ultrasound of soft tissues and joints].

: Sonography has become a reliable diagnostic method in musculo-skeletal diseases. It allows a simple and noninvasive examination of joints and soft tissues. Especially in rheumatic diseases meaningful findings can be obtained. In the present study first results of three-dimensional (3D) sonography of the musculo-skeletal system are reported. The method was first validated by examining healthy test persons and criteria for regular findings were defined. In the second part of the study an unselected group of patients with inflammatory and noninflammatory joint and soft tissue diseases were examined and the obtained results were compared with the findings of the conventional real-time sonography. Comparison of the 2D and 3D procedure showed a superiority of the 3D method with regard to the assessment of large (hip), middle-sized (elbow) and small joints (finger, toe). Additional information about the synovial space, the surface of the cartilage, and the thickness of the synovial membrane was provided by 3D sonography. Volumetry of joint effusions and Baker cysts was easier to perform and more reliable than with the conventional method. Soft tissue alterations could be delineated reliably, depending on their size. Our results demonstrate that 3D sonography can improve the diagnostics of musculo-skeletal diseases. In the future, 3D sonography should play an important part in the diagnosis of joint and soft tissue diseases.