[Ultrasound hard tissue detection for registration in orthopedics and traumatology].

The application of x-ray diagnostics for intraoperative navigation and for registration of hard tissue structures is restrained due to high radiation loads and the not given real time ability. Previous approaches with conventional ultrasonic imaging are only interactively applicable due to the high information content of soft tissue optimised B-mode-images. A pure image processing does not allow an automatic identification of individual structures, so that this must be done by the physician. To decrease the high expense of time, this report presents a concept for an adapted chain of rf-signal processing as well as an ultrasonic system for the contrast-enhanced representation of tissue borders. The system permits an exact measurement of the body geometry, which is demonstrated by determining the position of the pelvis entry plane.