Three-dimensional spatial registration and interactive display of position and orientation of real-time ultrasound images.

Ultrasound images may be difficult to interpret because of the lack of an image orientation display. To resolve this problem, a three-dimensional (3-D) ultrasound scanner has been constructed that provides spatial registration and display of position and orientation of real-time images while allowing unconstrained movement of the scanning transducer. It consists of a conventional sector scanner, a 3-D acoustical spatial locater, and a personal computer. It displays within each image the line of intersection of two image planes, a reference image, and a live image. This display guides and documents image positioning. The scanner's 3-D data also provide the potential for computergraphic modeling of organs, the ability to calculate volumes using nonparallel, nonintersecting image planes, and the capability for 3-D color flow mapping and measurement of Doppler angle.