Isometric, three-dimensional viewing of ultrasonograms.

This report describes a system that allows amplitude information to be used as a third dimension or aspect of display on B-scan ultrasonograms. The relative strength of reflected echoes can be shown on B-scan by means of gray scale, color coding, or on A-scan with amplitude deflection. With this new technique, called isometric display, superimposition of the A-scan trace on the B-scan allows preservation of these amplitude characteristics. The three-dimensional presentation can be rotated around any azimuth to provide isometric viewing of the ultrasonogram. Tissue may then be characterized on a more reliable basis than is permitted by independent analysis of outline and amplitude features.